CHAPTER 8: GUIDANCE ON EFFICACY REQUIREMENTS

Chemicals
Regulation
Directorate
Data Requirements Handbook
CHAPTER 8: GUIDANCE ON EFFICACY
REQUIREMENTS
CONTENTS
Section
Page
1
Introduction
2
1.1
Efficacy requirements
2
1.2
Meeting efficacy requirements
2
1.3
Contact information
3
2
Scope of Efficacy Requirements
4
2.1
Legislative basis
4
2.2
Areas to be addressed under PPPR
4
2.3
Differences in areas addressed under COPR
7
3
Meeting Efficacy Requirements
8
3.1
Introduction
8
3.2
Presentation of efficacy information
9
3.3
Levels of control expected to be demonstrated
10
3.4
Overseas evidence
12
3.5
Extrapolation
14
3.6
Public domain evidence
15
3.7
Data owned by others
16
3.8
Experimental Data
16
3.9
Conducting field trials
18
4
Situation-Specific Guidance on Meeting Efficacy Requirements
25
4.1
Extrapolation between glasshouse or growth room tests and outdoor use 25
4.2
Biological Control Agents and pheromones
25
4.3
Comparability of pesticide formulations
26
4.4
Guidance on extrapolation in specific situations
32
4.5
Numbers of trials required for major crops.
36
4.6
Pest populations required in trials
36
4.7
Information required in support of peripheral label claims
38
5
Efficacy Guidelines
42
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Introduction
The intrinsic biological activity of pesticides poses the potential for risks to operators,
consumers and the environment. Whilst methods are available to reduce exposure
and thus, reduce any risks (e.g. the use of protective clothing), no risk, however
small, can be considered acceptable unless there is a proven benefit from the use of
the pesticide. The main purpose of the efficacy consideration is to ensure that when a
pesticide is used as recommended on the label, a consistent benefit will be achieved.
These guidance notes are intended to provide an outline of the efficacy requirements
for approval and how these may be met. It is impracticable to set rigid guidelines for
all types of pesticides, thus the information given is intended only as guidance, and
the Environment Branch of CRD is always willing to discuss individual situations with
applicants in more detail where necessary.
1.1.
Efficacy requirements
The areas that need to be addressed in an efficacy submission are broadly
comparable for COPR and PPPR but with some changes of emphasis and a few
additions in the more recent legislation. If you are applying to register a pesticide you
will need to have done the following.
lxviii) Provided evidence to support all the claims for control that you have
included on the label.
lxix)
Demonstrated that the product is safe to the crops on which you
recommend its use.
lxx)
Demonstrated an acceptable level of safety to adjacent and following
crops.
lxxi)
Supported all peripheral claims such as rainfastness, use of mixtures,
safety to beneficial insects etc.
In some cases you may also be required to
lxxii)
Consider and address the risk of resistance developing to an active
substance.
lxxiii) Justify the dose you propose to specify on the label.
1.2.
Meeting efficacy requirements
The information we require you to provide may come from a range of sources,
detailed below, and must be presented in a suitable format, either as an efficacy
overview (for COPR applications only) or preferably as a Biological Assessment
Dossier (BAD). OECD format dossiers are also acceptable, provided all Annex III
efficacy requirements are addressed and the data summarised in an appropriate
format (see 3.2). In all cases you are advised to read the relevant detailed guidelines
that follow.
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Table 8.1: Sources of information to meet efficacy requirements.
Extrapolation
Provided a sound database is available it may be possible to
extrapolate information from one target or crop to another closely
related one, between different cropping situations or between
closely related formulations.
Public Domain
Evidence
Suitable information in published papers and books, including the
Weed Control Handbook.
Data owned by
others
Where data are protected they may be used if a suitable letter of
access is provided by the owner. Where confidential data are no
longer protected they may be used to support an application but
remain confidential.
Trials data
A programme of trials can be used to generate data specific to a
given product application. Trials can be conducted in the UK or
overseas though for the latter you should provide an acceptable
case detailing why they are applicable to UK conditions. If you are
planning to conduct trials please ensure you are familiar with any
relevant guidance, such as EPPO guidelines.
Please note that most efficacy data generated in the UK since 1998 must have been
produced by an Officially Recognised organisation. Other dates apply for elsewhere
in the EU. Further details are in section 3.8.1.
1.3.
Contact information
Should you have any query relating to efficacy, please use one of the following
contact addresses:
Environment Branch
CRD
Mallard House
Kings Pool
3 Peasholme Green
York YO1 7PX
26/11/2010
Tel: 01904 455775
Fax: 01904 455711
Email: [email protected]
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2.
Scope of Efficacy Requirements
2.1.
Legislative basis
The efficacy requirements for the registration of pesticides in the UK are defined in
the Control of Pesticides Regulations 1986 (COPR), as amended and the Plant
Protection Products Regulations 1995 (PPPR) as amended.
Under COPR pesticides can only be approved when Ministers are satisfied that they
can be used safely and effectively. CRD's requirements for approval were previously
outlined in the Registration Handbook and separate efficacy guidelines.
The PPPR implement the EC Council Directive 91/414/EEC which lays down specific
requirements for the information necessary for evaluating efficacy. These are detailed
below.
COPR will continue until all existing EC active substances are reviewed and placed
on Annex I (positive list). PPPR will apply to new active substances coming onto the
UK market and existing EC reviewed active substances that obtain Annex I listing.
2.2.
Areas to be addressed under PPPR
Under PPPR the data supplied must be sufficient to permit an evaluation of the plant
protection product covering the areas laid down in Directive 91/414 and subsequent
Directives such as 93/71, see The Applicant Guide for full details. In particular it must
be possible to evaluate the benefits that accrue from the use of a product, where
possible in comparison to suitable reference products and damage thresholds, and to
define its conditions of use.
Sufficient data must be supplied to CRD to confirm that the directions for use are
applicable over all the conditions likely to be encountered when used according to
the label recommendations, including for example regional and seasonal differences.
All the following areas must be addressed for a new active substance. Specific
products may be able to use information already supplied to support other products
containing the same active substance.
2.2.1. Preliminary tests
Summaries of preliminary tests, including glasshouse and field studies, used to
assess the biological activity of the product, must be submitted when requested by
CRD. Where this information is not submitted a justification which is acceptable to
CRD should be provided.
2.2.2. Dose justification
In order to clarify the dose response, doses lower than that recommended should be
included in some trials in order to enable an assessment of the minimum dose
necessary to achieve the desired effect.
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2.2.3. Effectiveness
Sufficient data should be provided to permit an evaluation of the level, duration and
consistency of control or protection or other intended effects of the plant protection
product, where possible, in comparison to suitable reference products.
Evidence should be submitted to show that the dose, timing and method of
application recommended give adequate control, protection or have the intended
effect in the range of circumstances likely to be encountered in practical use.
2.2.4. Crop Safety
The safety of a product to the main cultivars of the main crops for which it is
recommended should be demonstrated, including examination of the effects of crop
growth stage, vigour, and other factors which may influence susceptibility to damage
or injury. Effects on yield should also be determined where relevant. When treated
products are likely to be stored, the effect on the yield after storage, including data on
storage life should, be determined where relevant.
For herbicides, and for other plant protection products for which adverse effects,
however transitory, are seen during trials, the margins of selectivity on target crops
should be established, using twice the recommended dose.
Where adverse effects occur, but are claimed to be unimportant in comparison with
the benefits of use or because they are transient in nature, evidence to support this
claim is required. For herbicides and where necessary for other products
measurements of yield and quality should be submitted.
2.2.5. Resistance
Laboratory data and where it exists, field information relating to the occurrence and
development of resistance or cross-resistance in populations of harmful organisms to
the active substance(s), or to related active substances, should be provided.
Where there is evidence or information to suggest that, in commercial use, the
development of resistance is likely, evidence should be generated and submitted as
to the sensitivity of the population of the harmful organism concerned to the plant
protection product. In such cases a management strategy designed to minimise the
likelihood of resistance or cross-resistance developing in target species is required.
2.2.6. Quality and transformation processes
Sufficient information should be provided to permit an evaluation of the possible
occurrence of taint or odour or other quality aspects of plants or plant products after
treatment with the plant protection product.
Testing should be conducted initially on the main crops on which the plant protection
product is to be used, using, where relevant, the main methods of processing. Where
effects are observed tests should be conducted at the normal rate of application.
When the treated plants or plant products are intended for use in transformation
process such as wine making, brewing or bread-making and significant residues are
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present at harvest, the possibility of adverse effects should be investigated if there
are indications that the product could have an effect on the processes involved.
2.2.7. Following crops
Where there is evidence that significant biologically active residues of the active
substance, its metabolites or degradation products, which may have an effect on
succeeding crops, remain in soil or in plant materials up to sowing or planting time of
possible succeeding crops, observations should be submitted on effects on likely
succeeding crops. In addition, under EU Guidance Document on relevance of
metabolites in groundwater (Ref. Sanco/221/2000-rev10, dated 25 Feb 2003), there
is a requirement to assess the relevance of any groundwater metabolites. This must
include the biological activity of any metabolites and the potential risk to crops e.g.
from use of irrigation water.
2.2.8. Adjacent crops
Observations should be submitted on adverse effects on other plants, including the
normal range of adjacent crops, when there are indications that the product could
affect these plants via vapour drift. Consideration should also be given to the effects
of spray drift and the effectiveness of tank cleaning.
2.2.9. Plant parts for propagation
The safety of products to propagating material must be addressed, except where the
proposed uses preclude application to crops intended for production of seeds,
cuttings, runners or tubers for planting, as appropriate. Where there is sufficient
interval between application and harvest and no residues or metabolites are found in
the relevant plant parts it may be possible to address this issue by a case making
reference to residues and metabolism studies. Further advice on when data are
required is given in Efficacy guideline 306.
2.2.10. Observations on non-target organisms
Any effects, positive or negative, on the incidence of other harmful organisms,
observed in tests, should be reported. Any observed environmental effects should
also be reported, especially effects on wildlife and/or beneficial organisms.
2.2.11. Use in mixtures
Where there is a recommendation to use a product in mixture information should be
provided on the effectiveness and safety of such use. This includes both positive
recommendations for the use of mixtures to improve control and convenience
mixtures.
2.2.12. Use of products containing more than one active substance
Where an active substance is co-formulated in a product with one or more other
active substances all the above areas must be addressed. Particular attention must
be paid to justification for the inclusion of each active substance in the product, as
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well as a justification of the product dose and any resistance implications and
management strategy arising from such a co-formulation. The amount of data
generated using the co-formulated product to address these points will depend on
the data already available for any single active products, and whether there are
significant changes in use pattern. Additional guidance on the justification of
mixtures, particularly for insecticides, is available in Efficacy guideline 607.
The simplest case would be where two actives with different target ranges are coformulated and apply the same equivalent dose as the individual products. Provided
dose justification has been addressed for the actives applied alone then no further
data are required, although a case should be provided to confirm that the doses are
equivalent to those applied by each single active product. A limited number of trials
should be conducted to confirm the effectiveness and crop safety of the formulation,
and demonstrate that there are no adverse (antagonistic) effects.
If the co-formulated product contains active substances with overlapping activity on
particular targets, then evidence to support dose justification will be required.
Because of the potential effects of the combined activity, this is considered relevant
regardless of the relative doses applied in the co-formulated product compared with
the single active products. These data can be generated as part of the trials
programme to again demonstrate effectiveness and crop safety as discussed above.
For these co-formulated products, where it may be the case that significantly different
doses are applied, it is possible that a greater number of trials will be required
particularly if there are multiple targets.
Further information concerning formulation changes, and in particular changes to
active substance content are discussed in section 4.3.
2.3.
Differences in areas addressed under COPR
Under COPR less emphasis is placed on the following areas.
●
Preliminary tests
●
Trials guidelines
●
Resistance management
●
Quality and transformation processes
●
Adjacent crops
●
Plant parts for propagation
In addition there is no requirement for doses other than those recommended on the
label to be tested (dose justification) or for the effect of treatments on beneficial
organisms to be tested.
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3.
Meeting Efficacy Requirements
3.1.
Introduction
This section provides guidance on the general principles of meeting CRD's efficacy
requirements. Guidance on specific situations is provided in Section 4, SituationSpecific Guidance on Meeting Efficacy Requirements or as separate guidelines as
listed in Section 5.
Relevant information should be provided to support all direct and implicit claims
relating to plant protection that appear on a label. The information should cover the
range of circumstances likely to be encountered in practical use, including a
representative range of climatic, crop and agronomic conditions. The data can come
from a range of sources including:
●
Extrapolation of data supplied to support existing approvals - see section
3.5 (Extrapolation) and 4.3 (Comparability of pesticide formulations).
●
Public domain information such as published papers - see section 3.6.
●
Confidential information owned by others, provided you have been given
a legal right to access it - see Confidential information owned by others,
provided you have been given a legal right to access it - see The
Applicant Guide guidance document on the protection of data.
●
Experimental trials - see section 3.8.
For major crop/pest uses, information is likely to come primarily from field trials either
directly using the products, crops and target organisms of interest or by extrapolation
from appropriate trials. Other sources of information are likely only to be of use in
supplementing results from these sources. For qualified recommendations (see
section 3.9.4, Limited efficacy data for minor uses: Qualified recommendations) and
minor uses, good results from other data sources(s) could largely replace the need
for replicated trials.
Information from different sources should not be treated in isolation, but should be
drawn together to form an overall picture of how the proposed label
recommendations are supported by the evidence. For example, an extrapolation to a
related pest could be supported by evidence from results of user trials, or data from
trials carried out overseas might be supported by UK public domain evidence.
Applicants should note that well-researched and argued cases increase the chance
of an application being successful.
3.1.1. Biological control agents (including pheromones)
Biological control agents (BCAs) are micro-organisms used as pesticides and must
be registered in the same way as chemical pesticides. Pheromones and other
semiochemicals are substances that cause behavioural responses in insects and
may be used for example to repel insects or disrupt mating, they must also be
registered if used for pest control purposes. Because many of these agents occur
naturally, and in some cases require extremely small quantities to be effective they
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may have a reduced toxicological and environmental effects compared to chemical
pesticides. However, although in some cases they can be highly effective, BCAs
often have a lower level of effectiveness than chemical pesticides. Despite this they
have a role to play in pest control and can be important components of integrated
pest management systems. Although the efficacy data requirements for these agents
are broadly the same as for chemical pesticides, specific allowances are made for
their particular characteristics. Further information is given in sections 3.3 and 4.2.
3.2.
Presentation of efficacy information
The preparation of a case to explain how the supporting evidence supports the
recommended uses of the product is a requirement for all applications. This provides
an opportunity to explain and justify the proposed label and improves the efficiency of
the evaluation greatly reducing the queries that may arise.
Efficacy data submitted for evaluation under PPPR should be in the form of a
Biological Assessment Dossier (BAD). Efficacy data submitted for evaluation under
COPR, may be submitted in the format of either a BAD or an efficacy overview.
Separate guidelines for the preparation of Biological Assessment Dossiers and
Efficacy Overviews are available from CRD, see section 5, Efficacy Guidelines.
Guidance developed within the Standing Committee on Plant Health
(SANCO/3989/2001) identifies that as from 31 December 2004 all dossiers should be
submitted in OECD format on the basis of the OECD dossier guidance. CRD is
aware that there are differences with the OECD format compared to that of the
Biological Assessment Dossier, both in terms of covering all relevant data
requirements and also in the presentation format. CRD is therefore still prepared to
accept dossiers to the ‘old’ BAD format.
Where dossiers are submitted to the OECD format it is imperative that applicants
address all the requirements as detailed in EC Council Directive 91/414/EEC, and in
subsequent directives such as 93/71. In particular, areas such as impact on the
quality of plants and plant products, effects on the processing procedure, and effects
on the yield of treated plants must be addressed. In addition in the presentation of
efficacy studies, dose rates lower than recommended must be included and an
assessment of whether the dose is the minimum necessary for approval to be
recommended must be made. Applicants should also consider carefully the format of
the summary tables to ensure that all relevant information is presented, and are
advised to cross-reference with the examples of summary tables provided in Efficacy
guideline 101 (Preparation of a Biological Assessment Dossier) to ensure that the
relevant headings and information are included. For example, the OECD summary
table example does not include information on weed numbers in the plots, something
that is essential in determining the validity of the trial.
The OECD guidance is available at http://www.oecd.org/dataoecd/1/19/1944026.pdf.
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3.3.
Data Requirements Handbook
Levels of control expected to be demonstrated
The aim of the evaluation of the submitted efficacy information is to ensure the label
claims are supported and reflect the actual performance of the product. The
performance provided should typically be in line with a commercially acceptable
standard treatment unless the product has particular benefits such as specific activity
against a target, compatibility with biological control or use in anti-resistance
strategies when a lower level of effectiveness may be acceptable. Further information
is available in EPPO guideline PP 1/214, Principles of Acceptable Efficacy. The
following guidance broadly reflects the currently applied performance requirements
for label claims. This is not a rigid framework for label claims and, if other claims are
considered to be more fitting to the situation and product performance, these should
be requested. This may be particularly relevant to biological control agents where
levels of control may be variable or sensitive to environmental changes.
3.3.1. Pests
In considering data submitted towards justification of claims of effectiveness against
pests, a number of factors will need to be taken into account when considering and
interpreting the level of control demonstrated. These include the time of assessment
in relation to application, the duration of effectiveness and the potential for reinvasion, and any recommendations for repeat applications.
Table 8.2; Levels of pest control expected for effectiveness claims
Level of effectiveness
Label claim appropriate
Consistent control commonly above
80%
Control
Control, between 60 and 80%
Lower levels of control e.g. 40-60%;
lower in exceptional cases.
Useful level of control (moderate
control may also be used)
Some control/reduction (in numbers
or damage)
For a claim for effectiveness below 80% to be recommended for approval, the level of
control demonstrated for that pest must be considered worthwhile for protection of
the crop. Further justification will be required for such claims to be approved for
significant target pests where a high level of control would typically be expected, for
example where incidental control of a target is given when the application is directed
at a different target pest, or they may be related to a reduction in damage caused by
the target pest (e.g. slugs). For some pests particularly those affecting the quality of
the crop, higher levels of consistent control (i.e. above 85%) would need to be
demonstrated. Examples of pests falling into this category are pea moth and codling
moth.
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3.3.2. Diseases
Disease may be assessed as either severity or incidence. Measurement of disease
incidence is particularly useful when low levels of disease are present but may be of
little value when infection is more widespread, when severity is more likely to give a
useful measurement of disease control. There is normally no benefit in reporting
both. Table 8.3 indicates the levels of control expected to be demonstrated to support
label claims for diseases and should be used where either severity or incidence are
recorded as a percentage or other linear scale.
Table 8.3; Levels of disease control expected for effectiveness claims
Level of effectiveness
80% and above
60-80%
40-60%
Label claim appropriate
Control
Partial/moderate/useful level of control
Reduction/some control
These criteria are not appropriate in cases where disease control is assessed as a
score on a non-linear scale. These scales are often relatively coarse with as few as
four divisions. With such scales meaningful levels of control can be difficult to
determine unless disease pressure is relatively high. Table 8.4 indicates the levels of
control expected to be demonstrated to support label claims for diseases where
measurements are made on a non-linear scale. In addition, statistical analysis of
assessments on a non linear scale is generally not appropriate. Even the calculation
of means should be avoided. When recording and assessing such results it may be
better to assign letters rather than numbers to the steps on the scale to avoid the
temptation to analyse them numerically.
Table 8.4; Levels of disease control expected for effectiveness claims when
using a non-linear scale
Level of effectiveness
Consistently reduces disease to
below 20-25%, normally the lowest
class.
Reduces disease to<20-25% in
the majority of cases
Clear reduction in disease
Label claim appropriate
Control
Partial/moderate/useful level of control
Reduction/some control
For some diseases, particularly those affecting the quality of the crop, higher levels of
consistent control will need to be demonstrated. For a claim of control of seed borne
pathogens (e.g. bunt, loose smut, leaf stripe), a product needs to be 98% effective or
better. For leaf stripe and loose smut, control in the region of 85-95% would allow the
claim for moderate control with the condition that seed cannot be used for
multiplication purposes.
In some cases an argument may also be made for higher claims than are justified by
disease control alone. For stem base diseases of cereals, for example, a claim of
control may be appropriate even when disease control is not consistently above 80%,
if it can be shown that the treatment significantly reduces lodging and/or disease
levels are kept to a level where they have no significant effect on yield.
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3.3.3. Weeds
In arable and horticultural field crops, the label claim supported by a certain level of
weed control is as follows:
Table 8.5; Levels of weed control expected for effectiveness claims
Label claim appropriate
Susceptible
Moderately susceptible
Moderately resistant
Resistant
Level of effectiveness
Consistent control of 85% and above
(see below †)
More variable control, mean 75-85%, but
with results often above 85%
Variable control, Mean 60-75%, but
some results above this level.
Poor control below the levels given
above
† To ensure worthwhile levels of control of certain important weeds in field crops, all these
categories are raised with the susceptible rating being as follows: pernicious grass weeds
where seed return must be prevented, e.g. black-grass and wild-oats, 95% and above,
cleavers 90% and above.
For perennial weeds, assessments of control levels in the year following treatment
will be important in determining the claim allowed.
3.3.4. Repeat applications
In many situations a repeat application will be required (e.g. regrowth, subsequent
germination or reinvasion). The timing of assessments following treatment will be
important in determining levels of control. Providing the label clearly explains the
effectiveness of the product, the claims above are still appropriate.
3.4.
Overseas evidence
Information from work carried out overseas may be acceptable to support an
application. However the relevance of any overseas evidence should be carefully
considered and a case made based on the parameters most relevant to the particular
use under consideration. The level of supporting detail included for overseas data
should be at least the same as that expected from UK trials. This includes the
requirement that organisations conducting work in EU member states are officially
recognised where a scheme exists at the time (See section 3.8.1, Official recognition
and Efficacy guideline 110)
The relevance of the conditions under which the trials were conducted to the
proposed conditions for use should be demonstrated. This would usually be done by
comparison to the general conditions that the crop or situation would experience in
the UK. The major issues are detailed below. The list is not exhaustive, and
applicants may be aware of other factors that might influence relevance in specific
cases. Applicants are therefore encouraged to consider the areas that are relevant to
the use in question, rather than submitting all information, some of which may be
irrelevant (e.g. soil type for foliar acting pesticides). Applicants may wish to construct
a general case for use of data from a particular area which could then be used as a
basis for future applications involving trials in that area.
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3.4.1. Climate
Typically, information such as mean maximum and minimum day and night
temperatures and rainfall (note that as well as monthly means, intensity of rainfall
may also be useful) could be required. Other factors such as humidity, wind speed
and intensity of sunlight may also be useful depending on the activity of the pesticide.
It is for the applicant to decide on the relevance of these individual aspects, but
generally the closer the locality of the trials is to the UK the less extensive is the need
for full climatic data. It may be useful to present a comparison of the relevant
conditions in UK and overseas trials presented in the data package.
The Crop Protection Association (CPA) produced a climate justification paper which
was agreed with PSD. This defined an area of Northern Europe within which climate
may be considered comparable. Subsequent to this, EPPO produced the guideline
‘Guidance on comparable climates’ (PP 1/241(1). This divides Europe into four
regions, within which climate is considered comparable. The UK is within a defined
region very similar to that drawn up in the original UK CPA paper. This guidance is
considered to supersede that of the original CPA paper and should be used instead.
It is also important to remember that climate is only one part of the case for
justification of non-UK data, and the other relevant factors discussed in this section
will still need to be addressed.
3.4.2. Edaphic conditions
For soil-applied products it is important to record soil types (converted where possible
to the Soil Survey of England and Wales soil texture system1), organic matter content
and pH. In addition it may also be important to record soil moisture content/deficit
over the duration of the trial.
3.4.3. Agronomic conditions
Cultural conditions and agronomy, (e.g. cultivations used, application methods,
cultivars, fertiliser regime, relative times of planting and harvest) may need to be
considered if it is thought that these differ from UK conditions.
3.4.4. Differences in target pest pressures
Specific details on the target pest, and whether the conditions encountered in the
overseas trials are likely to represent a harsher or less harsh test of the product (for
both effectiveness and crop safety), will sometimes be necessary. Such detail would
include differences in the epidemiology of diseases, population dynamics of insects
and other pests and differences in races of organism to be controlled. For example
damson-hop aphid has a longer period of immigration to hops and invasions are
more severe than on the Continent. Overseas data are therefore unlikely to be
relevant to the UK situation.
Rural Development Service Technical Advice Note 52; Soil Texture.
http://naturalengland.etraderstores.com/NaturalEnglandShop/UserFiles/Files/tan_52.pdf
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3.5.
Data Requirements Handbook
Extrapolation
Provided a sound database is available it may be possible to extrapolate information
from one target or crop to another closely related one, between different cropping
situations or between closely related formulations. Extrapolation may be possible for
control of the same target on other crops, for control of related targets on the
same/other crops, or between crops for crop safety. It may also be possible to
extrapolate from all uses of a product of a similar formulation containing the same
active substance(s), e.g. from professional to home garden use of a product.
Extrapolation may be used to form either all or part of the supporting case for
approval.
3.5.1. Availability of a sound database
An important factor when considering extrapolation is that the efficacy data used as
the basis of the extrapolation must be adequate in quality and quantity, i.e.
extrapolation must be from a sound database.
If conditions have been such as to test the product severely, and it has still performed
consistently well, relatively few results will be sufficient to support the extrapolation.
However, there will be times when the very nature of the situation gives rise to high
variability and more trials will then be necessary. If extrapolation is supported by an
efficacy database for more than one use (e.g. where the pest is controlled on two or
more different crops, or where crop safety has been demonstrated on a range of
crops) then extrapolation is more likely to be acceptable.
3.5.2. Biological basis for extrapolation
A sound biological basis for extrapolation is essential. A close taxonomic relationship
cannot always be assumed to be well correlated with overall biology and behaviour of
the target organism(s). For example, the summer fruit tortrix moth is not controlled by
many insecticides that are effective against fruit tree tortrix moths. In addition, the
same organism may not behave in the same way for different crops/situations.
Equally, crops that are taxonomically related may be quite different, for example in
their growth habit, leaf surface or in terms of the parts of the plant that are harvested.
All aspects of the pest biology and behaviour, and the crop biology and uses should
be carefully considered in making a case for extrapolation.
3.5.3. Choice of use from which to extrapolate
If a trials programme is being designed to support an extrapolation, it is advisable to
consider which crop/pest combinations are likely to be most suitable for this purpose.
It should not be assumed that the crop with the largest area in the UK should
automatically be the subject of the greatest number of trials. It may be better to put
more emphasis on a less widely encountered crop. For example in the case of
herbicides, if the crop is less competitive with the weeds, or in the case of
insecticides/fungicides if the organism to be controlled is usually more difficult to
control on the less widely grown crop. This is because the case for extrapolation to
less susceptible/more competitive crops is likely to be more convincing. The same is
true for considerations of crop safety. If data are provided from a crop that is
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considered to be more susceptible to damage by pesticide treatments then an
extrapolation will be easier to justify.
It should also be borne in mind that the pest problems for any one crop may be more
diverse and more common than for another, so that the probability of obtaining data
useful for extrapolation to other crops may be correspondingly higher.
3.5.4. Further guidance on extrapolation
Further guidance on extrapolation in specific situations is contained in section 4.4
below.
In addition, a guidance document titled ‘Proposal for extending and harmonizing
efficacy and crop safety extrapolations to reduce the need for efficacy trials on minor
crops’ is available. This document was produced by PSD under a Commission
contract. It makes proposals for efficacy extrapolations to facilitate the approval of
extensions of use onto minor crops and against minor targets. This guidance has
now formed the basis of EPPO guideline PP 1/257(1) ‘Efficacy and crop safety
extrapolations for minor uses’ which lays out the general principles for extrapolation,
and includes as an appendix various specific examples. It should be noted that
further work is underway to produce specific EPPO guidelines for specific target/crop
situations. Applicants should refer to this general guidance as well as any future
guidelines.
3.6.
Public domain evidence
The use of public domain evidence, such as papers published in scientific journals,
conference proceedings etc, is an acceptable way of supporting label claims. It is
important for the applicant to explain how any information directly supports the claims
made. In addition, if the evidence cited is from field or glasshouse trials conducted
outside the UK, then a case arguing the relevance of the conditions to the UK will be
required. The following factors should be considered when using such information.
3.6.1. Formulations
The efficacy of many active substances is affected by formulation and therefore,
applicants should give due consideration to whether the formulation(s) in the public
domain data directly support the product under consideration for approval. For
guidance on this aspect, please see section 4.3, Comparability of pesticide
formulations.
3.6.2. Data protection
When considering the use of public domain data, applicants should be aware that
CRD consider labels of other similar products (containing the same active substance)
to be supported by data which are not in the public domain. An application that
makes identical or very similar claims to other products will not, therefore, be
considered acceptable unless directly supported by adequate data. You should
consult The Applicant Guide guidance document on the protection of data for
guidance on CRD's data protection policy.
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3.6.3. Weed Control and Pest and Disease Control Handbooks
CRD have always accepted recommendations given in the 'Weed Control
Handbook2' with no further data required, as long as the proposed label uses are
within the range given in the Handbook and the formulations are comparable.
However the 'Pest and Disease Control Handbook3' is based on product labels and
not peer reviewed public domain data, and therefore cannot be used to support
applications.
3.6.4. Presentation of public domain data
When making use of public domain evidence, it is not sufficient to simply provide a
copy of the original papers. The relevant methodologies and results should be
properly summarised in the submission and discussed in sufficient detail to
demonstrate their relevance to the proposed label use. It may be helpful to submit a
copy of the references used, especially of the more relevant ones. Applicants should
be prepared to supply a copy of any references not included in the submission, if
necessary with an English translation, on request. Failure to do so may result in a
lower level of approval than that requested or the affected uses being omitted from
the recommendation for approval. Information on the use of efficacy data in the public
domain was issued in the Pesticides Register, Issue 5, May 1995 (available from
HMSO, ISSN 0955-7458).
3.7.
Data owned by others
Where an application relies on confidential data owned by a third party, for example
data used to support a previous application from another company that is still under
data protection, a valid letter of access must be submitted. These must be either
original signed copies or copies of letters previously submitted to CRD. Full guidance
on letters of access, including a suggested proforma, are available in The Applicant
Guide guidance document on letters of access.
3.8.
Experimental Data
3.8.1. Official recognition
With minor exceptions all efficacy data generated since 1st Jan 1998 must have been
generated by an Officially Recognised Organisation.
The UK scheme for ‘Official Recognition of Efficacy Testing Organisations’ (’Official
Recognition’) was designed in response to Community Directive 91/414/EEC (as
amended by Commission Directive 93/71/EEC), which states that all efficacy testing
for registration purposes must be carried out by ‘Official’ or ‘Officially Recognised’
efficacy testing organisations. In other Member States ‘Official Recognition’ is
commonly referred to as ‘Good Experimental Practice’ (GEP).
Fryer, JD and Makepeace, RJ (Eds)(1978) Weed Control Handbook Volume II / Recommendations. Blackwell
scientific publications, Oxford.
2
Scopes, N and Stables, L (Eds)(1989) Pest and Disease Control Handbook. British Crop Protection Council,
Bracknell.
3
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The UK ‘Official Recognition' scheme came into force on 1st January 1998. Efficacy
data generated in the UK after this date must be carried out by ‘Officially Recognised’
efficacy testing organisations.
For full details of the data that falls under the requirements of Official Recognition see
Efficacy guideline 110.
Data produced in the UK
All applications for products approvals (i.e. new substances, committee stream,
normal stream etc.) which contain efficacy data generated from trials carried out in
the UK after 1st January 1998 must be supported by ‘Official Recognition’ certificate
numbers (e.g. ORETO 001) for all of the organisations concerned. The ‘Official
Recognition’ categories stated on the certificate must be relevant to the type of data
submitted (e.g. Stored Crops), and it must be valid for the period during which the
data were produced. This also means that, within the Biological Assessment Dossier,
applicants must clearly identify which organisations undertook the work.
Data produced elsewhere in the European Union
When an application for product approval contains efficacy data produced elsewhere
in the European Union, CRD require evidence of whatever constitutes ‘Official
Recognition’/‘GEP’ in that Member State (e.g. copies of relevant and valid
certificates). This evidence should demonstrate that the organisation carrying out the
work was ‘Officially Recognised’ at the time. The exceptions to this are where the
data were produced before an ‘Official Recognition’ scheme was established in that
Member State or where the data were generated by ‘Official’ testing stations.
However, in some Member States ‘Official’ testing stations are also certificated.
‘Official Recognition’/‘GEP’ schemes vary slightly between different Member States,
in terms of their start dates, scope and the evidence required to achieve certification.
This is because Member States were individually responsible for implementing the
requirements of Directive 91/414/EEC.
3.8.2. Designing a trials programme
The trials programme should be designed to cover each distinct region of the country
within which the conditions and practices are broadly similar, and where it is intended
to use the product. Within each region trial sites should be distributed across the
main relevant growing areas and should include the main relevant plant cultivars
occurring in each region.
The programme should be designed to assess the performance of the product in
each region under the conditions likely to occur there during the relevant period(s) of
the year. Such studies should produce adequate data to permit conclusions to be
drawn concerning the product's performance in respect of climate, soil type, plant
cultivar, pest, pathogen or weed species as appropriate under relevant conditions of
use.
The programme should normally extend over a period of at least two years in order to
assess the effect of under seasonal differences. In some situations results obtained
from a lesser period may be acceptable, for example when considering closely
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similar products, a change in formulation or method of application, certain protected
crops, minor uses, certain home garden products etc.
3.9.
Conducting field trials
The sections below cover only basic principles. Further guidance and advice on
meeting data requirements in specific situations is given in Section 4 and in separate
guidelines listed in Section 5. Detailed specific advice on conducting trials is given in
the guidelines for the evaluation of plant protection products issued by the European
and Mediterranean Plant Protection Organisation (EPPO). EPPO guidelines are
recognised by CRD, and in the European Directives associated with the registration
of plant protection products, as the standard reference for trials methodology. As
such they should be followed unless a sound justification can be given for not doing
so. EPPO guidelines are obtainable from:
EPPO, 1 rue Le Notre, 75016 PARIS, FRANCE.
3.9.1. Number of trials
The applicant should aim to provide data to support the claims made on the product
label and to provide evidence of the suitability and crop safety of the product for the
use envisaged. The number of trials required to achieve this depends on many
factors such as:
●
The extent of the knowledge already gained on the active substance or
product
●
The importance of the crop/animal/produce and the significance of the
harmful organism
●
Availability of testing possibilities e.g. rare occurrence of the harmful
organism
As a general rule, a total of ten trials results demonstrating efficacy and ten
demonstrating crop safety are required for approval. For insecticides and fungicides
some, or possibly all, data on crop safety may be obtained by appropriate
assessment of effectiveness trials. A case may be made for fewer trials to be
accepted, for example where there is a large amount of supporting evidence or when
there is a very high level of consistency in different trials. In all cases the trials
programme should be carried out over at least 2 years.
Additional claims will also require ten trials, for both effectiveness and crop safety.
Again a case may be made to reduce the number of trials in certain circumstances.
For example CRD only normally require three consistent trials for minor crops or
targets, provided data on a relevant major target have already been considered, and
a level of extrapolation may be permitted between different crops for a single target
organism that affects more than one crop.
3.9.2. Location of field trial sites
The crops chosen for experiments may be specifically grown for experimental use or
be part of crops grown for commercial purposes, but in all cases should be grown
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according to normal commercial practice. They should be located in areas
representative of those in which the crop and harmful organism normally occur.
If there is a possibility that soil types may affect the action of a product, sites should
be chosen which are representative of the range of soil types typically encountered.
The experimental site should be uniform and crops should preferably not be under
any stress other than that attributable to the problem to be treated (except where the
effects of stress are being investigated). All other cultural operations apart from that
being tested, should be according to normal practice and should be recorded.
3.9.3. Trial design
The design, analysis and reporting of trials should be in accordance with EPPO
guidelines 152 and 181 and where available more specific the EPPO guidelines
applicable to the situation.
The design of the trial should, where relevant, permit a statistical evaluation. Usually
a randomised block design is adequate. Each block should generally contain one plot
treated with the pesticide to be evaluated, one treated with a suitable reference
product (positive control) and an untreated control. The plots should be randomly
distributed within the block. Consideration should be given as to whether it is likely
that design and analysis as a trial series is appropriate rather than, or as well as,
analysis of results from the individual trials conducted. This may affect trial design as
a more statistically powerful test is achieved through the use of larger numbers of
trials than through greater numbers of replicates in each trial. See EPPO guideline
152 and Efficacy guideline 111 for further information on the statistical analysis of
efficacy data.
The design of the trials should not be made any more complicated than is required by
the objectives of the test. Where it is necessary to introduce into the experiment
factors, in addition to the treatments of the pesticide under study at the
recommended dose, such as various times of application or other doses, this can be
accomplished by splitting the main plots into sub-plots, provided that the size of the
sub-plots are still sufficient to allow a reliable evaluation.
Plot size
The most suitable plot size depends upon many factors, including the particular crop,
pest, disease or weed situation, the mobility of the target organism, the available
equipment for application of the treatment and harvesting of the crop. Since guard
rows/areas often have to be included, the overall plot size should be sufficiently large
to allow the net plots on which periodic sampling and evaluation of the crop yield or
harvest are carried out to be of adequate size. Guidance on the minimum net plot
size is usually indicated in individual EPPO guidelines.
The number of replications required depends on plot size, number of treatments and
uniformity of distribution of the target organism. The number of replications required
is also related to the particular techniques employed. Further specific guidance is
given in EPPO guidelines, but four replicates is normally considered to be the
minimum number for field experiments. Three replicates are usually acceptable for
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the evaluation of post-emergence weed control by herbicides, provided the yields are
not intended to be measured.
Control and untreated areas
Untreated areas are normally an integral part of a trial. There should be at least one
per replicate. If there are ten or more experimental treatments there should be at
least two untreated plots in each replicate, provided there are at least four replicates.
Where there are only three replicates then eight or more treatments would require at
least two untreated plots. If maintaining the untreated plots at the same area as
treated plots represents an unacceptable economic loss their size may be reduced,
but not the number of untreated plots. Except in trials designed to test safety to the
crop, these plots may be treated after they have been evaluated. Exceptionally (e.g.
aphids in commercial hops) the requirement for untreated control plots may be
waived. Positive controls should be suitable approved products, but in appropriate
cases there may need to be (in addition or instead) a control not exposed to the
harmful organism.
Target organism
As far as possible the target organism should be present, or be expected to occur
evenly distributed and at a level of agronomic importance. The organism must be
identified and described by its full scientific name. Where relevant, subspecies,
variety and pathotype, etc. should be stated. Stage of growth, density, frequency or
level of infestation/infection and other factors having a bearing on the situation should
be noted and, if necessary, be quantified before treatment.
A naturally occurring infestation/infection is preferred. If artificial inoculation of a
pathogen or introduction of a pest or weed is necessary, this should be recorded and
the procedure described. Untreated and standard treated plots should be infested,
inoculated or populated in the same manner as plots to be treated with the product
under test. Consideration should be given to allowing a suitable period of time
following inoculation for the infection or pest to become established before treatment.
Additional useful information (especially on crop safety) may be obtained in
appropriate
cases
from
the
inclusion
of
treated
but
uninoculated/uninfested/unpopulated plots.
Trials should include different stages of growth of the harmful species where relevant.
Trials should also include different strains or races where these are likely to show
different degrees of susceptibility. Evidence of effect in appropriate representative
species, cultivars or breeds having resistance to the harmful organisms in question
should be provided where such resistance is known or suspected.
Dose
The dose at which the product is likely to be recommended should be included in
trials. In trials to test efficacy, doses above and below the recommended dose
should, where appropriate, also be included. In trials to determine safety to crops, the
recommended dose, and for herbicides at least double the recommended dose,
should be tested. For insecticides and fungicides inclusion of a higher than
recommended dose is not a requirement for crop safety unless effects are seen at
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the recommended dose. Nevertheless inclusion of a greater than recommended dose
for such products may help to give greater confidence in the results obtained and
should therefore be given due consideration. Any adjuvants, e.g. spreaders or antifoaming agents which it is intended to recommend should be mixed with the product
should be applied with it in the trials. It may be advisable to test the product and the
adjuvants separately to detect a phytotoxic effect.
The test material should not be applied in mixture with other products, fertilisers, or
other substances (other than adjuvants and diluents) except where the purpose is to
obtain information on the performance of such mixtures, or where the inclusion of
such products or substances would normally be considered as good agricultural
practice. Where two or more products in tank mixture are being tested, the individual
products should be tested in the same trial.
Application method and water volume
The method and conditions of application should be the same, or as like as possible
to that to be recommended for the product. The application pattern used in trials
should be similar to that used in commercial practice, both in particle size and
distribution and in deposition on the treated surfaces. For sprays the volume and
diluent should be as recommended for commercial use except where these factors
are being evaluated.
The water volumes that are to be recommended on the product label should be
considered to be a pre-requisite for the protocols of trials to demonstrate the
effectiveness and crop safety of a product. For situations where a dilution rather than
a specific volume of water per hectare is to be recommended trials should reflect the
recommendation. Where appropriate information on crop or canopy size should be
provided. For proposed uses on apple, applicants should refer to the UK developed
dose adjustment scheme (‘PACE’), which is based on a ‘crop adjustment factor
(CAF)’. CAF values should be recorded in any apple trials. Further details are
available from Efficacy guideline 403 ‘Provision of information on tree canopy size in
efficacy and residue trials in apple orchards’. It is accepted for most arable and
horticultural crops that the range of water volumes, using standard hydraulic nozzles,
is 200 - 400 litres/ha. Trials data using any water volume within this range are
acceptable for such label recommendations. For all other label recommendations
there is a need for trials data using the recommended water volumes or a reasoned
case as to why trials data using a different volume are applicable.
Timing and treatments
The timing to be recommended in practice should be tested. Inclusion of earlier and
later timings, where appropriate, may provide additional useful information. Where
repeated application is the norm the timing of the first application should be that
expected to be recommended for the product being tested. Different frequencies of
application may be compared. The optimum interval between applications may have
to be established by experimentation.
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Recording and assessment
Records of the weather before, at and after treatments should be kept and relevant
data included in the reports of experiments. Rainfall, frost, air and soil temperatures,
and air humidity are usually the most important factors influencing results. Other
measurements e.g. wind speed and direction may be required in some
circumstances. If experimental crops are not grown in their usual environment this
should be stated (e.g. field crops in pots or under temporary or permanent shelter
from the weather).
Variety of crop, stage and vigour of growth and all other relevant information should
be recorded on the date of treatment. Crop growth stage should be defined either by
using an accepted code (e.g. growth stage keys published by EPPO), or by a
detailed description. A pre-treatment assessment is often also essential to determine
the level of infestation/infection and stage of development of the harmful organism
and/or stage of growth and condition of the crop.
One or more post-treatment assessments should be made and these should be
timed so as to elucidate the maximum of information on the behaviour of the product
and its duration of effect, whilst also avoiding undue damage to the experimental
area and needless expenditure (frequent inspection may be necessary to minimise
the number of assessments). Assessment at different stages of growth of the target
organism and/or of the crop may be required. Further specific guidance on
assessment methodology is given in EPPO guidelines.
Results should be assessed by counts or measurements wherever possible. Only
when the use of such assessment methods is inappropriate should any other
methods, such as scoring or grading be used. Any such method should be related to
an absolute count or other measurement on the untreated or the standard treatment
(or both). When scoring schemes are to be used, widely accepted scoring systems
such as those in EPPO guidelines should be used in preference to others.
Where appropriate data should be statistically analysed, and methods fully described.
Raw data need not be submitted but should be held by the applicant for reference in
case of a need for clarification. See EPPO guideline 152 and Efficacy guideline 111
for further information.
3.9.4. Limited efficacy data for minor uses: Qualified recommendations
An application for pesticide approval is expected to include evidence to support the
claims made about the efficacy of a product. However, this evidence may be difficult
or uneconomic to obtain where sporadic pests or other problems are concerned or
where small scale crops are involved. As a result, it has been agreed that in certain
circumstances approval may be given on the basis of limited evidence of
effectiveness and/or crop safety. However, all such applications must still meet the
full requirements with regard to safety to the health of humans, animals, non-target
plants and the environment, before any approval can be given.
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Qualified recommendations for minor uses
Qualified recommendations on the basis of limited efficacy data may be considered
for:
●
Use on a minor crop/situation.
●
Infrequent treatment of a major crop/situation.
●
Use to control a sporadic pest/disease/weed/other problem.
The decision on what constitutes a ‘minor use’ rests with the Registration Authority.
Potential applicants are advised to contact CRD’s Environment Branch to discuss
whether or not the proposed use qualifies as ‘minor’ prior to making an application.
Evidence of efficacy
To support an application for approval under these arrangements the evidence
submitted must satisfy CRD that there is a reasonably high probability that the claims
of the products effectiveness and crop safety (where applicable) are justified.
Evidence to support a qualified efficacy recommendation will usually take the form of
a justified extrapolation from data on the pest on other crops or from data on related
pests. Where relevant, foreign data may be submitted. Recorded field observations
may also provide useful evidence, particularly on crop safety.
Uses given approval on the basis of limited efficacy data must be clearly identified as
"Qualified Minor Use Recommendation[s]" on the label under 'recommendations for
use'.
3.9.5. User derived evidence
In some situations efficacy data to support an application for approval can be
generated from trials conducted by a commercial user. In some cases large scale
user trials may be more appropriate than replicated small plot field trials. For
example, for crop safety in top fruit the variability from tree to tree can be very high,
so assessments from small plot trials may detect only gross effects.
When carrying out user-trials applicants should ensure pesticides are used within the
conditions of approval, or that they are the subject of the relevant experimental permit
(see The Applicant Guide guidance document on application streams).
The acceptability of user-derived evidence
Under Commission Directive 93/71/EEC, all efficacy data should be generated by ‘an
official or officially recognised testing facility or organisation’. The UK ‘Official
Recognition of Efficacy Testing Facilities’ (ORETO) scheme makes provision for
user-derived evidence by allowing such work to be carried out by suitable qualified
personnel under the direct supervision of an ‘Officially Recognised’ facility. The UK
ORETO scheme came into force on 1st January 1998. The acceptability of userderived evidence generated after this date is conditional upon the supervising
organisation supplying a relevant and valid ‘Official Recognition’ certificate.
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Conducting user trials
The usefulness of results from user trials is largely dependent upon the
appropriateness of the assessments, and the quality of the recording and reporting of
the methods and results. The applicant should play an active role in supervising such
trials, thereby ensuring that the maximum benefit is gained. Detailed guidelines on
conducting user trials are available in Efficacy guideline 112.
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4.
Data Requirements Handbook
Situation-Specific Guidance on Meeting Efficacy
Requirements
This section gives specific guidance on the use of information to support applications
and on generating information to support approvals in some of the most frequently
encountered situations. Further guidance for other situations can be found in the
efficacy guidelines a list of which is presented in section 5.
4.1.
Extrapolation between glasshouse or growth room tests and
outdoor use
The proceedings of the BCPC/SCI Conference "Comparing glasshouse and field
pesticide performance II"4 report that glasshouse testing is not necessarily a good
indicator of field performance. This means that for field-applied products, CRD judge
that glasshouse-produced data are generally of limited value in establishing field
performance. For products recommended for use under controlled conditions (e.g.
glasshouse products, grain storage products, palatability testing of rodenticides),
glasshouse/laboratory testing can be more relevant.
Applicants should make a clear case as to why an extrapolation from glasshouse to
outdoor use is valid. Conditions in a glasshouse can affect the structure of plant
surfaces, as well as pest biology, thereby changing the effectiveness and crop safety
of a product. Particular caution is required in considering crop safety data obtained in
protected conditions. In some cases the protected crops may be "softer" (perhaps
because of a thinner layer of surface wax) and thus be more easily damaged. In
other cases the damage on outdoor crops may be influenced by factors not found
under protection (e.g. sudden temperature changes, frost, abrasion by soil particles,
wind, drought, water-logging). It is suggested that applicants study the proceedings
of the BCPC/SCI Conference "Comparing glasshouse and field pesticide
performance II" before attempting to justify such extrapolations.
4.2.
Biological Control Agents and pheromones
The extent of data required for BCAs and pheromones is generally the same as for
other pesticides. However, consideration will be given to the nature of any particular
agent. The following illustrate some of the issues that applicants should take into
account when designing a trials programme.
●
Use in protected environments: Many BCAs are only normally used in
protected environments such as glasshouses. Because of the narrower
range of environmental conditions typically encountered all pesticides for
use in protected crops generally require fewer trials to demonstrate
efficacy.
H G Hewitt, J Caseley, L G Copping, B T Grayson and D Tyson. (1994) Comparing Glasshouse and Field
Pesticide Performance II. Proceedings of an international symposium held at the University of Canterbury 12-14
April 1994.
4
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4.3.
Data Requirements Handbook
●
Environmental conditions: Many biological control agents are sensitive
to particular environmental conditions. Where BCAs are not used in
protected environments the dossier must provide adequate evidence of
the effect of environmental conditions on the products effectiveness in
relation to the label recommendations. This can normally be achieved by
conducting trials over two years.
●
Crop safety: Agents that are not applied as broadcast sprays onto plants
have reduced potential to cause phytotoxic effects. Although crop safety
must always be considered a relatively simple case may often be
sufficient.
●
Pheromone trials: Because of the potential for pheromones and other
semio-chemicals to disperse over a wide area it may not be always
feasible to conduct trials with replicated or untreated control plots.
Applicants are advised to talk to CRD before setting up trials
programmes and, where relevant, refer to Efficacy Guideline 220 ‘Data
requirements and trials design for mating disruption products’
Comparability of pesticide formulations
Formulation changes have the potential to influence the efficacy of a product as
many co-formulants are added to a product to increase effectiveness against the
target organism, directly or indirectly. This section is intended to give general
guidance on the extent of efficacy testing required when, for the purposes of
registration, a formulation is claimed to be comparable with another; and existing
data on the ‘old’ formulation' are used to support approval of the ‘new’ formulation.
4.3.1. When is supporting data required?
Changes to surfactants, such as wetters or spreaders, including to the amount of
surfactant, are normally regarded as changes that will require efficacy testing. It
should be remembered that a change that improves effectiveness can have the
opposite effect on crop safety and vice versa. Similarly changes in solvents or
carriers can impact on performance and unless changes are considered minor (e.g.
to a chemically very similar solvent) then efficacy testing is required. For granule
carriers, the comments under ‘Herbicides used pre-emergence’ apply to other
granule formulations e.g. insecticides and nematicides. Note that it is the applicants
responsibility to justify the similarity of two formulations where they believe
formulation differences are sufficiently similar that efficacy testing is not required.
However there are some cases where supporting efficacy evidence is not required to
show that the two products have comparable efficacy
Minor formulation changes.
The following changes to formulations are considered minor and do not usually
require supporting efficacy evidence provided the change does not affect the amount
of active substance or other co-formulants that are applied.
●
Changes in the source of active substance.
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●
Change in substances added to preserve the formulation in the container
or to improve safety to non-targets, e.g. preservatives and anti-freeze except for vertebrate control bait products.
●
Changes in substances used to identify the formulation, e.g. dyes.
●
Some changes to the fertiliser content of granular herbicide fertiliser
based granules. The nature of the manufacturing process for granular
herbicide fertiliser products means that often several different forms of
nitrogen, phosphorus, potassium or other elements may be included. It is
considered unlikely that variation in fertiliser base will affect the
performance of the product. CRD will accept a range of formulation
details for the fertiliser base component, for these products alone.
Formulation details should include the expected concentration range of
all the raw materials used in the production of the fertiliser base, and the
minimum specification of the final formulated product. The latter must
include the N:P:K ratio, active ingredient content, particle size, density
and dust content. CRD must be notified of any additional materials used,
and data or information must be provided showing that the change has
no adverse effect on the product.)
●
In general, changes of less than 10% in the amount of any formulation
component applied, including the active substance, are considered to be
minor and as such require no further data. With respect to efficacy, it is
the amount of active substance and co-formulants applied to the target
that is important, not the content in the formulation itself.
Attempting to significantly change a formulation, by making a series of
minor changes in content (i.e. each within 10%) that would not in
themselves require supporting data, is not acceptable. CRD will refer
back to the original formulation for each change and where appropriate
request supporting data.
Some products contain two or more co-formulants with the same
function, e.g. wetters. Where this is the case, providing the co-formulants
concerned are chemically similar, it may be acceptable to change the
quantities of them by more than 10% providing the overall content of that
group of co-formulants is not changed by more than 10%. A case to
justify similarity of the co-formulants concerned should be provided.
Note of caution: Many applications for changes in formulation do not
contain any information on the chemical nature of the co-formulants, nor
any justification of the similarity between them. In the absence of any
further information, CRD will generally err on the side of caution and
refuse approval for the revised formulation.
Some products contain more than one active substance. Where changes
are made to the ratios of the active substances within a product, even if
these changes are less than 10% for each active substance, further
efficacy consideration may be required, particularly in terms of
effectiveness and dose justification. In particular it is not appropriate to
make successive small changes to the active substance content which
ultimately result in a significant difference in the ratio, unless there is
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appropriate data to address the issues of efficacy, dose justification and
crop safety, as relevant
Uses/types of products
For the following uses and types of product, although differences in formulation may
exist, these are unlikely to affect efficacy and thus efficacy data are not required to
show that the two formulations are comparable.
Simple salts in water
Products that are simple salts in water are taken to be
comparable to other products containing the same salt of an
active substance Products containing different salts of the
same active substance are taken to be comparable if both
salts disassociate equally in water. Examples of active
substances which can be formulated in this manner are,
arylalkanoic acids (the 'hormone' herbicides), dicamba, and
chlormequat
Herbicides used pre- It is generally accepted that once a formulation is present in
emergence
soil then the co-formulants have no effect on performance.
This means that for a product which is used before neither
the crop or weeds have emerged, no efficacy data are
required to establish comparability. If used pre-emergence
of the crop on emerged weeds then only data on
effectiveness are required. If used before weeds emerge on
an emerged crop then only crop safety data are required. A
case may be provided to reduce the data required where the
herbicide is only active through the roots.
Exceptions to this are granular and capsule suspension
formulations or slow release formulations, for which data
may be required. For a change in size of granule or
alteration of the material from which release occurs, data are
required to show that efficacy is not affected. For the latter
this may be based on physical property data, such as active
substance release rate.
Other
types
of For soil-applied/compost incorporated products other than
products used pre- herbicides, a case for a reduced comparability package may
emergence
be considered, depending on the type of activity and the
considerations of release rate and coverage given above for
herbicides.
Seed treatments
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It may be possible to submit data showing that the loading of
the active substance on treated seed is the same for both
the old and new formulations rather than carry out field trials.
Please consult CRD’s Environment Branch for further
advice.
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Fumigants
Data Requirements Handbook
Where the product is a fumigant then provided either; that
gas is evolved from the formulations at a similar rate, or gas
levels are maintained through monitoring and redosing, the
formulation is unlikely to affect efficacy.
Groups of formulations
Companies may have access to existing data which demonstrate that a range of
formulations of the same active substance are similarly effective and crop safe.
Where this is so, a case may be accepted that it has already been demonstrated that
formulations containing this active substance are broadly comparable. If only
formulations of a similar type have been shown to have comparable efficacy then the
case for comparability may be restricted to that formulation type, e.g. if three
suspension concentrate (SC) formulations control a certain target then extrapolation
to another SC might be possible but extrapolation to an emulsifiable concentrate
might not.
In some cases, one formulation can be recommended at a lower dose of active
substance than another formulation containing the same active substance. This could
indicate that there is variation in the performance of different formulations containing
that active substance, therefore broad comparability has not been established and
efficacy comparability work will be required.
Knowledge of previous formulation changes with a particular active substance.
The intended change in formulation from the ‘old’ to the ‘new’ product may be similar
to a change which has already taken place with that active substance or one with
very similar properties. If the applicant has access to existing data which shows that
this change in formulation did not affect efficacy, then comparability testing may not
be required.
An applicant may have access to existing data that show that a number of
formulation changes have taken place with an active substance and efficacy is
always equivalent. In which case, it may be possible to make a case for a reduced
level of comparability work when approval is sought for a further ‘new’ formulation.
Please Note: The examples given above are not exhaustive. If you are undertaking
another change in formulation that you consider does not require efficacy testing, or
where existing knowledge suggests a reduced package would be satisfactory or a
case could be made, please consult CRD’s Environment Branch.
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4.3.2. Extent of efficacy testing required to demonstrate comparability
A label will have been established for the approved product taking into account the
acceptability of the levels of pest control achieved and whether any crop effects seen
will affect yield. The tests described below are only relevant to establishing
comparability of two formulations so that similar label claims can be made for the
proposed product.
lxxiv) Generally, results from five appropriate trials are required. Both
effectiveness and crop effects should be assessed in these trials on a
selected range of target species and crops claimed on the label. Not all
species and crops on the label need to be tested. If the label is very
diverse in terms of the claims made then more trials are likely to be
required, depending on the type of action of the product. On the other
hand, where a particular target or crop can be identified as a good
indicator of comparability, all trials may be carried out on this target/crop.
lxxv) Target organisms for examination in trials should be selected from the list
of organisms claimed as controlled on the label. Those selected should
include targets that are less well controlled by the product or are known
to be more difficult to control with that type of product. Reduced doses
can be included to provide a more severe test of comparability of
effectiveness.
lxxvi) Crop safety should be examined on crops stated to be acceptable for
treatment on the label. Crops selected should include any that are known
to be more sensitive to the product and thus most likely to show damage
to give the most testing examination of comparability.
lxxvii) Trials carried out in one growing season should be acceptable as long as
they are carried out in different conditions and preferably in different
situations, to reflect those possible from the label instructions. One
seasons testing may also be sufficient where disease or pest challenge
in that season has been adequate, or where the product is used under
controlled conditions, e.g. glasshouse. Existing data on the extent to
which the active substance is affected by varying conditions should be
taken into account. Otherwise trials will need to be carried out over two
growing seasons.
lxxviii) Where long-term control of a target organism is claimed, then
assessment may need to be carried out over a reasonable period as a
change in formulation may affect longer term control, e.g. for perennial
weeds control in the following year may need to be assessed.
lxxix) Where there are differences between results statistical analysis should
normally be carried out, unless such analysis can be shown to be not
relevant.
Acceptable levels of product performance
Usually, if these tests show that the effectiveness and the crop safety of the two
formulations are the same, then no further tests are required to establish
comparability. However, if in most trials the formulations are comparable, but due to
adverse conditions, the level of efficacy of both formulations at recommended doses
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is below that considered acceptable, this may not in itself be a sufficient
demonstration of comparability. In this case, further trials may be required to assess
whether the two formulations are still comparable in trials where conditions are such
that the ‘old’ product does give the expected level of efficacy.
4.3.3. Further investigation
Where the trials show that the proposed formulation is less effective or less crop safe
than the 'old' formulation, data on the 'new' formulation should stand alone. In this
case a more detailed examination of its efficacy will then be required. This is likely to
include a full range of trials, some taken to yield, so that the label claims are
supported by evidence where only the ‘new’ formulation has been used.
4.3.4. Formulations where supporting data are out of protection
In order to access data out of protection for another formulation, comparability trials
are required which compare the proposed formulation with the one for which data out
of protection are available. As a general rule, the formulation to which bridging is
proposed should always be the original formulation which was supported by a full
data set and not to any subsequent formulation approved as a minor formulation
change, or one supported by limited bridging data.
In some situations, that formulation may no longer be available. As such, direct
bridging is not possible. However, provided the applicant conducts trials across a
broad and representative range of uses, and the proposed product performs as
expected for such a product type, then a reduced data package can be accepted on
the basis of the out of protection knowledge that the formulated active substance is
effective for the uses sought.
This approach may mean that a rather greater number of trials are required than
when bridging directly to an out of protection formulation, particularly if wishing to
gain approval for all the original label claims, but still enables a reduced data set
compared to the full data set required for a new and protected use to be used. The
same principle applies if the trials are conducted outside of the UK where an
appropriate non-UK approved product is being used as the standard instead of the
UK approved product for which data is out of protection.
Note that if the numbers of trials are limited, the label claims may be restricted to the
actual situations (i.e. crop/pest combinations) tested in the trials. In this situation,
further data would be needed to add additional pests/crops to the label later.
4.3.5. Other efficacy aspects
Data on some other efficacy aspects, for example, following crops and resistance,
are generally taken to be related to the active substance. Therefore formulation
comparability evidence is not normally needed to make use of existing data. For
many other aspects, the fact that formulation comparability has been established
should provide the basis to substantiate that existing data can be used for the new
formulation, e.g. dose response, biological compatibility, effects on quality,
transformation processes, and plants or plant products to be used for propagation.
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●
4.4.
Data Requirements Handbook
Vapour drift is an important concern when considering effects on
adjacent crops. Existing data on this aspect can be used if the applicant
can establish, either by way of a reasoned case or tests, that the vapour
drift of the 'new' formulation is no greater than that of the ‘old’
formulation.
Guidance on extrapolation in specific situations
Just as it is often necessary to carry out separate trials for effectiveness and for crop
safety, it will usually be necessary to give separate consideration to these two
aspects when extrapolation is proposed. The following notes provide more detailed
guidance to help applicants to write well reasoned and acceptable cases in each of
the specific areas. Please note previous comments under 3.5.4 on development of
guidance by EPPO in this area.
4.4.1. Guidance on extrapolations for crop safety
The use of a case based solely on extrapolation as evidence of crop safety will
usually only be successful when considering extensions of approval from major to
minor crops. However, there are other circumstances where it is appropriate to
consider extrapolations for crop safety between major crops or from minor to major
crops.
Crop safety can vary considerably between different plant species and between
different pesticide products, so before making an extrapolation applicants need to
consider both these factors. The following basic questions are a guide to the areas
which might need to be considered:
lxxx) Are any of the crops on which the product is already approved related
taxonomically to the new crop?
lxxxi) Is the morphology of the crops concerned similar?
lxxxii) Are the growing conditions and uses of the crops similar?
lxxxiii) Is the extrapolation from a major crop(s) to a minor crop?
lxxxiv) Are there adequate crop safety data showing a good margin of safety for
the crop(s) from which extrapolation is required?
lxxxv) Is the mode of application (e.g. dose, water volume, timing) the same for
the crops involved in the extrapolation?
For some product/crop combinations the answer to all the above questions will be
'yes', in which case there will be a strong case for extrapolation. In some such
instances it may be appropriate to make a Qualified Recommendation (see section
3.9.4). A negative answer to one or more of the above questions does not
necessarily preclude extrapolation, but should prompt applicants to question the
degree to which the extrapolation is valid. In such cases it may be that extrapolation
can still provide part of the case for crop safety, with some further data required to
confirm its acceptability. Alternatively extrapolation may not be possible, for example:
where the product has shown crop damage on some crops; where the crops
concerned are significantly different; where the crop is known to be particularly
sensitive. In these cases a stand-alone crop safety package will be required.
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Applicants should note that when using extrapolation as part of an application for
approval, a soundly reasoned argument should be presented in the efficacy overview
as to why that extrapolation is considered acceptable. The above list of questions
could be used as a basis for such an argued case, with any factors relevant to the
particular situation also being taken into account.
4.4.2. Guidance on extrapolations for effectiveness - Diseases
If data show that a fungicide is capable of controlling certain diseases in a number of
situations then a case may be accepted that control of the same or a related disease
is possible in other situations. For example if data are available showing good control
of four species of rusts on ornamentals then it should be possible to extrapolate to
other rusts of ornamentals. However the epidemiology of a pathogen and the
effectiveness of control agents can be different on different host plants, or even on
different parts of the same host plant. For example, Botrytis cinerea has a wide host
range, is a wound parasite but can also infect fruits, and on tomato can cause
disfigurement of fruits ("ghost spot") without establishing a progressive infection. In
such cases extrapolation may not be acceptable.
CRD have previously accepted extrapolations from the following diseases on one
crop to the same disease on another crop with no supporting data (see Table 8.6).
Table 8.6: Disease Extrapolations
Disease/pathoge
n
Fusarium nivale
(Seedling blight)
Bunt/covered
smut
Eyespot
Powdery mildew
Rhynchosporium
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Extrapolation
From
To
Spring
wheat
Winter wheat
Winter
barley
Wheat
Barley
Spring
Winter wheat wheat
Winter barley Spring
barley
Spring
Winter wheat
wheat
Spring
Winter barley
barley
Chapter 8 - 33
Notes
Same pathogen and the test is more
severe on W. wheat
Same pathogen and W. barley is less
susceptible
Similar pathogens; control relies
purely on disinfection of spores on
the seed surface
Same pathogen and similar disease
development
Same pathogen and similar disease
development
Same pathogen and similar disease
development
Same pathogen and similar disease
development
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Data Requirements Handbook
4.4.3. Guidance on extrapolations for effectiveness - Insects and mites
Depending on how mobile a compound is on a particular plant type and how and
where insects or mites feed on a plant their accessibility and hence the effectiveness
of a pesticide can vary greatly. Some individual species of pests feed in different
places on different crops and this may affect the activity of a product against the
same pest on different crops. However, in many cases it is possible to make wellargued extrapolations. It is sometimes possible to make a case that the pest for
which approval is sought feeds in a similar way to others for which activity has
already been proved.
If data are available showing that an active substance can control a number of
species of insects or mites feeding in the same situation on the plant (e.g. on the
roots or within leaf mines) then extrapolation is more likely to be accepted. For other
pests, it may be possible to argue that the timings of treatment are coincident.
However it must be emphasised that the biology of the pest and its location on the
plant has to be taken into account.
CRD has previously accepted extrapolations from the following pests on one crop to
the same pest on another crop with no supporting data (see Table 8.7).
Table 8.7: Insect and mite extrapolations
Pest species
Two spotted
spider mite
Extrapolation
From
To
Mites on hops,
Mites on runner
strawberries, and beans and
tomatoes
raspberries
Field and
laboratory data
for Oryzaephilus
surinamensis
and/or Sitophilus
granarius
O. surinamensis
and/or
S. granarius
Tribolium species
and Cryptolestes
ferrugineus
For spray
applications on
leather jackets
Certain
caterpillar
species
Applications on
cereals, beet and
grass
Garden pebble,
large white and
diamond-back
moth
Other crops e.g.
peas, beans and
rape
Small white and
cabbage moth
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Notes
Sufficient data should have
been acquired during the
trials to be confident of
extrapolation
Extrapolation is possible if
lab. data are available
showing similar mortality to
O. surinamensis and/or
S. granarius and the target
pest is likely to receive the
same exposure.
Same species having the
same biology on different
hosts
Caterpillars are a less
challenging target.
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4.4.4. Guidance on extrapolations for effectiveness - Weeds
The required level of control of a particular weed and the level that can be achieved
by a particular herbicide can be very different in different crops depending on a
variety of factors. These factors include competitiveness of the crop, timing of weed
control, times of sowing/planting, time/method of harvesting and ease of separating
crop seeds and weed seeds. If enough is known about the required levels of weed
control, the competitiveness of the crop situation and the factors affecting
achievement of those levels in both crops, it would be possible to make a well-argued
case for extrapolation from one crop to another. For example, taking competitiveness
into account:
Table 8.8: Weed extrapolations
Situation
A - Arable - competitive
crops
B - Arable/horticultural poorly competitive crops
C - Other situations non-competitive crops
Crops
Cereals, grassland,
oilseed rape
Notes
Extrapolation accepted
within group and from B or
C.
Sugar beet, peas,
Extrapolation accepted
onions, linseed,
within group and from C,
brassicas
but not A.
Orchards, HONS,
Extrapolation accepted
amenity vegetation, land within group but not from A
not intended to bear
, and possibly from B.
vegetation
4.4.5. Extrapolation between professional and home/garden products
For information on extrapolation from professional products to use in the home
garden, see Efficacy guideline 211.
4.4.6. Further guidance on extrapolation
A guidance document titled ‘Proposal for extending and harmonizing efficacy and
crop safety extrapolations to reduce the need for efficacy trials on minor crops’ is
available. This document was produced by PSD under a Commission contract. It
makes proposals for efficacy extrapolations to facilitate the approval of extensions of
use onto minor crops and against minor targets.
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4.5.
Data Requirements Handbook
Numbers of trials required for major crops.
Decision making schemes - trials numbers for cereal pests
Figures 8.1-8.3 indicate the number of trials required for major cereal pests, diseases
and weeds. The diagrams assume that all the data substantiating the efficacy of a
product are from specifically conducted efficacy trials, using recognised methodology
(see section 3.9 Conducting field trials), and conducted in situations directly relevant
to the proposed use of the product. In all cases this guidance assumes that the
results fully support the claims being made.
Oilseed rape and brassicas
Specific advice on oilseed rape and brassicas is presented in Efficacy guideline 405.
4.6.
Pest populations required in trials
It is essential that populations of the target organisms (weeds/pests/diseases) in
efficacy trials are present at agronomically significant levels in order to provide a
sufficient challenge to the treatments applied. In most cases, the size of the pest
population present immediately before treatment application will be the most relevant
measure of the initial pest challenge. However, in the case of pre-emergence
herbicides or fungicides claiming ‘protectant’ activity for example, this information will
not be available and the pest levels on untreated plots at later assessment timings
will need to be considered instead.
Note that the initial level of the target organism is not the only measure of an
adequate pest population. Pest levels on untreated plots must be maintained, or
increase, throughout the duration of the trial. Trials where adequate initial pest levels
on untreated plots subsequently decline (in the absence of treatment) are unlikely to
provide evidence that a sufficient pest challenge existed on the treated plots. [Note
however that trials where such a decline occurs may, in some circumstances, be
used to provide evidence of crop safety.]
It is not appropriate to have a prescriptive list of ‘minimum populations’ for all possible
target organisms but indicative levels for weeds, pests and diseases in various crops
are given below. Note that it would normally be expected that at least some trials
would be conducted on pest populations much greater than the minimum acceptable
population. However, provided the majority of trials within a data-set have aboveminimum pest levels, the occasional near-but-below-threshold level should not be
considered unacceptable.
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4.6.1. Weeds
In general, a minimum population of 5 plants/m 2 for each weed species being tested
is required for a trial to be considered valid. However, particularly for major weeds
such as black-grass or cleavers, some data should be submitted from much greater
population levels.
For grass weeds, the definitive assessment will often be the ‘head count’, and in
general the minimum acceptable number of tillers in the untreated plots is 20/m². In
the case of major grass weeds such a black-grass, ideally some data should be
submitted from trials where populations exceed 100 heads/m 2.
Overall, trials should cover a range of weed population sizes and should include
some large, challenging populations.
4.6.2. Diseases
For most diseases, an incidence of at least 5% plants infected or 5% leaf area
infected is the minimum level required. For curative claims this should be the level of
infection at application. For preventative claims it will be the level at assessment. In
some cases, depending on the pathogen, the assessment methodology and sample
size, higher disease levels may be required. For example, diseases of oilseed rape
are often assessed on a scale of 1-4 and disease levels must reach at least the
second point on such scales, which may be equivalent to 50% infection. For
diseases such as potato late blight, measurement of the delay in foliage blight
reaching a specific level of infection (usually 25% leaf area affected) would be
acceptable. In trials with low levels of infection, there may still be scope to use these
data by increasing the sample size assessed and providing a case and justification
why the data would be acceptable.
Certain seed-borne diseases on cereals e.g. bunt and smuts, typically occur at very
low levels in commercial seed. However use of seed with low infection levels in trials
may be acceptable where there is potential for very rapid multiplication of the
pathogen and where very high levels of control are required. However, sample size
for assessment may need to be increased.
Artificial inoculation of a pathogen may be used to obtain challenging levels of
disease. If artificial inoculation is used, the whole trial should be inoculated evenly
and a suitable period of time must be allowed to permit disease establishment before
treatments are applied. Natural or artificial level of infection of seed lots should be
assessed prior to the trial by an appropriate method.
Note that it would not generally be acceptable to have all trials with infections at or
close to the minimum level. At least some trials in a series should have infection
levels considerably above the minimum.
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4.6.3. Pests
Specific agronomic treatment thresholds have been established for many of the main
crop/pest combinations. These are widely publicised by advisory organisations and
in general these should be viewed as the minimum level for efficacy trials. Where no
treatment-threshold exists, the occurrence of agronomic damage on untreated plots
may be used to justify the pest population. The majority of trials should be carried
out on naturally-occurring pest infestations but artificial introduction may be used to
boost pest populations in some trials. Where this is used, sufficient time must be
allowed for the introduced individuals to become established before treatments are
applied.
Note that it would not generally be acceptable to have all trials with infestations at or
close to the minimum level. At least some trials in a series should have infestations
considerably above the minimum.
4.7.
Information required in support of peripheral label claims
4.7.1. Rainfastness
Examination of this subject has shown that rainfastness is a complex issue. It is
affected by a large number of factors such as the type and intensity of the rain, the
physical and chemical characteristics of the pesticide, dose, formulation, temperature
and relative humidity.
Expert advice is that most pesticides are rainfast within 12 hours. Therefore, it may
be possible to support a rainfastness claim of 12 hours or more without data. For
claims below 12 hours, data or a case will be required. Consideration will, of course,
need to be given as to whether it is appropriate for a rainfastness claim to appear on
the product concerned.
4.7.2. Label statements which require no supporting data
In drawing up this guidance the provision of a list of label statements which do not
require supporting data was considered. It was concluded that many directions for
use, warnings and other pieces of advice may be included on product labels without
the need for supporting data. However, to draw up a standard list was felt to be unnecessarily restrictive, not only because it would tie applicants to a standard wording,
but also because in some cases the acceptability of such label statements without
data varies from product to product.
In drawing up labels applicants are therefore encouraged to consider the basis for
each label statement they make (e.g.; a statement may be based on general
knowledge for spray applications, on accepted ‘good agricultural practice’ or on data
previously submitted for the active substance), and then to clearly explain the basis in
the efficacy overview. In many cases it will be possible to justify the use of a label
phrase with a very simple statement.
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Figure 8.1; Decision-making scheme to determine number of disease control trials
required for registration of cereal fungicides.
Major diseases ~ 10 acceptable trial results:
powdery mildew, brown rust, yellow rust,
Septoria tritici, Septoria nodorum, eyespot,
sharp eyespot, take-all, bunt (seed-borne),
fusarium seedling blight, septoria seedling
blight.
Winter Wheat
Minor diseases ~ 3 acceptable trial results:
tan spot, ear diseases (sooty moulds, fusarium,
botrytis), bunt (soil-borne ), loose smut,
penicillium blue mould.
Major diseases 10 acceptable trial results:
powdery mildew, brown rust,
rhynchosporium, net blotch, leaf stripe, loose
smut.
Minor diseases 3 acceptable trial results:
eyespot*, take-all*, snow rot, cochliobolus
foot rot.
Winter Barley
Claim allowed on basis of extrapolation
from wheat:
yellow rust* (brown rust on barley also
required in support), Fusarium seedling
blight*, covered smut*
* if adequately supported on winter wheat.
No
Spring Barley
Are sufficient
data available on
winter barley?
Yes
If adequately supported on winter wheat
and/or barley, claims for all relevant
diseases listed above allowed on basis of
extrapolation except for the following
diseases on oats:
powdery mildew, crown rust, fusarium
seedling blight (3 confirmatory trials required
on each disease).
Minor Cereals
Including; oats,
spring wheat, durum
wheat, rye, triticale.
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Claims for all barley diseases listed above
allowed on basis of extrapolation except:
leaf stripe (10 trials required)
powdery mildew, loose smut (3 confirmatory
trials required)
Chapter 8 - 39
Efficacy
Chemicals
Regulation
Directorate
Data Requirements Handbook
Figure 8.2; Decision-making scheme to determine number of pest control trials
required for registration of cereal insecticides.
Major pests 10 acceptable trial results:
summer aphids, slugs, wireworms,
leatherjackets, wheat bulb fly and frit fly.
Winter Wheat
Minor pests 3 acceptable trial results:
thrips, blossom midges, opomyza and
BYDV vectors*
* if adequately supported on winter barley
No
Major pests 10 acceptable trial results:
BYDV vectors.
Winter Barley
Are sufficient data
available on
winter wheat?
Major pests 3 acceptable trial results:
summer aphids, slugs, wireworms,
leatherjackets, wheat bulb fly and frit fly.
Yes
Minor pests*
thrips, blossom midges and opomyza.
*Claim allowed on basis of extrapolation
from wheat if pest biology and pest/crop
interaction comparable.
No
Minor Cereals
Including; oats, spring
wheat and barley,
durum wheat, rye,
triticale.
Are sufficient
data available on
winter wheat
and/or winter
barley?
Yes
Claim for all relevant pests listed above
allowed on basis of extrapolation from
winter wheat/winter barley if pest biology
and pest/crop interaction is comparable.
An example of an unacceptable
extrapolation would be BYDV between
winter and spring crops.
Note: where different methods or timings of application are proposed (e.g. admixture and broadcasting of slug pellets,
soil application and deadheart spray against wheat bulb fly), each should be fully supported.
26/11/2010
Chapter 8 - 40
Efficacy
Chemicals
Regulation
Directorate
Data Requirements Handbook
Figure 8.3; Decision-making scheme to determine number of weed control trials
required for registration of cereal herbicides.
Active against
grass weeds
Major weeds 10 acceptable trial
results:
black-grass ,wild oats, common couch,
barren brome, annual-meadow grass
Other important grasses 5 acceptable
trial results, (3 trials if related species
controlled):
bents, rye-grasses, onion couch, meadow
brome rough meadow-grass
Investigate
Herbicidal Activity,
e.g. screens, early
trials
Active against
broad -leaved
weeds
Major weeds ~ 10 acceptable trial
results:
cleavers, volunteer potatoes
Other broad-leaved weeds ~ 3 acceptable
trial results per species:*
e.g. common chickweed, volunteer oilseed
rape, scentless mayweed, common fieldspeedwell, field pansy, common poppy, fat
hen,
If related weeds controlled less trials may
be required
*Activity should be assessed against a
range of broad-leaved weeds on at least 20
sites giving approx. 50 individual results.
Sporadic weed - one result:
A very uncommon weed where related
weeds are well controlled, e.g. thale cress
if other crucifers controlled, fig-leaved
goosefoot if fat hen controlled.
26/11/2010
Chapter 8 - 41
Efficacy
Chemicals
Regulation
Directorate
5.
Data Requirements Handbook
Efficacy Guidelines
The guidance above presents general advice for addressing efficacy requirements for
approval. More detailed advice is available in the following documents, all of which
have been agreed with the efficacy working group of the CPA. A paper copy of any of
these is available on request: Further guidelines will be issued from time to time, and
an
up
to
date
list
is
maintained
on
CRDs
website
at
http://www.pesticides.gov.uk/guidance/industries/pesticides/topics/pesticideapprovals/pesticides-registration/data-requirements-handbook/ecotoxicology-andenvironmental-fate-working-documents.
NUMBER
101
102
103
104
110
111
112
113
114
115
116
117
TITLE
NOTES
General guidance on generating data and submitting applications
Guidelines for the Preparation of a Biological Assessment
See also EPPO
Dossier
1/181
Historical only
Guidance on the Preparation of an Efficacy Overview
use 101
Efficacy Requirements for the Re-registration of Products
containing Existing Active Substances after Inclusion in Annex I
Guidance for Efficacy Sifting of New Active Substance
Submissions
Official Recognition of Efficacy Testing Organisations
See also EPPO
Guideline on Statistical Analysis of Efficacy Data
1/152
Guidance on Conducting User Trials
Requirements for an Efficacy Assessment and Availability of
EPPO standard
Relevant Guidance
1/223
Guidance on the Status and Use of EPPO Guidelines for the
Efficacy Evaluation of Plant Protection Products
Guidance on Numbers of Trials in Target Crops for
EPPO standard
Demonstration of Efficacy and Crop Safety
1/226
EPPO standard
Minimum Effective Dose
1/225
Groundwater metabolites – guidance on efficacy aspects
14/10/10
Chapter 8 - 42
Efficacy
Chemicals
Regulation
Directorate
NUMBER
201
202
203
204
205
206
207
208
209
210
211
220
Data Requirements Handbook
TITLE
Application or situation specific guidelines
Fabric Treatments with Residual Insecticides
Fumigants for the Control of Insect and Mite Pests of Stored
Products
Pesticides for Admixture with Stored Cereals to Control Insects
and Mites
Space Treatments - Against Flying Insects
Larvicides in Animal Rearing Units
Baits for the Control of Houseflies in Animal Rearing Units
Hand Held Aerosols and Ready for Use Sprays Against
Crawling Insects
Seed Treatments - Efficacy and Physical/Mechanical Data
Requirements
Propagule Fungicide/Insecticide Treatments Data Requirements
- Efficacy and Physical/Mechanical Data Requirements
Simulation of Aerial Application to Field Crops Using Ground
Based Sprayers
Efficacy Data Requirements for Home Garden Products
Data Requirements and Trials Design for Mating Disruption
Pheromone Products
Crop Safety Guidelines
Superseded by
EPPO 1/242
301
Guidance on Taint Testing
302
Cleaning Application Equipment – Efficacy Aspects
Effects on Non-Target Crops of Highly Active Herbicides Including Mixtures and Sequences
303
Superseded by
EPPO 1/243
304
Transformation processes
305
Cleaning Application Equipment – Small scale jar test protocol
306
Plant parts for propagation
307
Quality Parameters - Cereals
Crop Specific Guidelines
Efficacy Testing of Apple and Pear Fungicides and Insecticides
in the UK
Guidance Document on the Trials Requirements for a Potato
Haulm Desiccant
Provision of Information on Tree Canopy Size in Efficacy and
Residue Trials in Apple Orchards
Data Requirements for PGR Products in Pome Fruit (preharvest, post harvest and ‘in store’ applications)
Data Requirements for Oilseed Rape and Brassica Pests,
Diseases and Weeds
Data Requirements for Turf Fungicides, Herbicides, Insecticides
and Plant Growth Regulators
Pest/Disease/Weed specific Guidelines
Evaluation of Molluscicides
Requirements for a New Late Blight Fungicide for Potatoes
Guidelines on Efficacy Tests for Rodenticides
Guidelines on Efficacy Testing of Mammal and Bird Repellents
Requirements for Products used for Mole Control
401
402
403
404
405
406
510
530
590
591
592
NOTES
14/10/10
Incorporated in
EPPO 1/135
Chapter 8 - 43
Available on
request
Efficacy
Chemicals
Regulation
Directorate
NUMBER
601
602
603
604
606
607
608
611
630
Data Requirements Handbook
TITLE
Chemical and Control Specific Guidelines
Resistance Warnings on Labels of Insecticide and Acaricide
Products.
Resistance Warnings and Restrictions on Labels of Professional
Herbicide Products
Fungicide Resistance Label Advice and Restrictions
Efficacy Data Required For Tank Mixtures and Sequences of
Pesticides
Resistance Risk Analysis and use of Resistance Management
Strategies
Insecticide Mixtures: Justification for Use and Implications for
Resistance Management in the United Kingdom
Using Non-toxic Slug Traps when Assessing Slug Activity and
the Risk of Damage in Winter Wheat and Oilseed Rape
Guidance on the Restriction of Use of High Resistance Risk
Herbicides
Data Requirements for Aqueous Dispersions of Sulphur
14/10/10
Chapter 8 - 44
NOTES
See also EPPO
1/213
Efficacy