Effect of Potassium Fertilization on Growth, Yield and Quality of... A.M. El-Bassiony Vegetable Research Department, National Research Center, Cairo, Egypt.
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Effect of Potassium Fertilization on Growth, Yield and Quality of... A.M. El-Bassiony Vegetable Research Department, National Research Center, Cairo, Egypt.
Journal of Applied Sciences Research, 2(10): 780-785, 2006 © 2006, INSInet Publication Effect of Potassium Fertilization on Growth, Yield and Quality of Onion Plants. A.M. El-Bassiony Vegetable Research Department, National Research Center, Cairo, Egypt. Abstract: Two field experiments were carried out during the two successive seasons of 2003-2004 and 2004-2005 atthe Experimental Station ofNational Research Center in Shalakan (Qalubia Governorate) to study the effect of soil application potassium sulfate (50, 100, 150 and 200 Kg/Fed.) and foliar application of potassium oxide (1g/L) as a stimulated dose. Obtained data showed that the best plant growth (plant length, number of leaves/plant and fresh weight of leaves) and highest yield and bulb quality were observed with soil application of 200Kgpotassium sulfate. Foliar application of potassium oxide alsohas a positive effect on plant growth, bulb yield and bulb quality. Key words: Onion , potassium , foliar application, growth, yield , quality INTRODUCTION Table 1: Physical and chemical analysis of the soil at the experimental sites. A- Physical analysis 2003 2004 Soil texture Clay loam Clay loam Clay(%) 47.80 48.30 Silt(%) 29.50 28.53 Sand (%) 21.34 21.63 B- Chemical analysis Ca (meq/L.) 2.00 2.50 Mg (meq/L.) 2.50 2.60 Na (meq/L.) 3.65 3.20 K (meq/L.) 0.32 0.51 N (meq/L.) 141 183 P (meq/L.) 4.90 5.01 HCO3 (meq/L.) 2.00 2.30 CL (meq/L.) 1.78 3.06 Fe (p.p.m) 17.80 18.20 Zn (p.p.m) 1.10 1.05 Mn (p.p.m) 7.56 7.74 Cu (p.p.m) 13.55 14.71 Organic matter (%) 2.04 1.36 E.C (mmohs at 25 °C 1.55 1.05 PH. 7.77 7.87 Onion is considered one of the most important vegetable crop in Egypt. Increasing productivity of onion with good quality is an important target by the growers for local market and exportation. Chemical potassium fertilizer became a high expensive fertilizer in Egypt, so farmers ignored using it. Foliar fertilization is more economical than root fertilization due to the higher degree of applied nutrients more efficient [1]. Abd El-Al et al[2] found that Increasing potassium as a soil application up to 150 Kg/fed. had a significant effect on growth characters, i.e. plant height, number of leaves/ plant, fresh and dry weight of whole plant as well as total yield and its components. Also gave the highest percentage of TSS, N. P. and K. Many investigators reported that potassium affected plant growth of onion[3-6]. In addition, potassium fertilizer increased onion yield[7-9] and increased dry weight, K and P uptake [10,11]. Potassium foliar spry increased plant growth[12,13] on tomato;[14] on potatoes; yield and quality [15,16] on tomato, as well as chemical composition[12,13] on tomato. The aim of this work is to improve yield and quality by applying potassium fertilization as soil and foliar application on onion plants. 200 Kg/Fed.) and foliar application of potassium oxide K2O (1g/L) as a stimulated dose on growth and productivity of onion plants. Onion seedlings cv. Giza 20 were transplanted on 15th and 17th of December 20032004 and 2004-2005 seasons respectively. The design of the experiments was split-plot with four replicates, where the potassium sulfate as a soil application were distributed in the main plots and potassium oxide foliar application were arranged in the sub-plots. Potassium sulfate was applied at two equal amounts, the first dose was applied one month after transplanting and the second dose added two month later. Foliar application was applied at two times the first time was MATERIALS AND METHODS Two field experiments were carried out during the two successive seasons of 2003-2004 and 2004-2005 at the Experimental Station of National Research Center at Shalakan (Qalubia Governorate) to investigate the effect of soil application of potassium sulfate (50, 100, 150 and Corresponding Author: El-Bassiony, A. M., Vegitable Research Department, National Research Center, Cairo, Egypt. E-mail: [email protected] 780 J. Appl. Sci. Res., 2(10): 780-785, 2006 one month after transplantingand the second time was ten days later. The experimental plot contained six ridges, each with 70cm width and 3.0 m long. The normal agricultural treatments of the growing onion were practiced as usually followed in the commercial productionof onion. The physical and chemical properties of the experimental soil are presented in Table (1). During the vegetative growth period, samples of 8 plants were taken at 150 days after transplanting and the plant length, number of leaves/ plant and fresh weight of leaves and bulb were recorded. At harvesting time (180 days from transplanting) the yield of bulbs as ton/fed. was calculated. In the same time samples of 10 bulbs from each experimental plot were taken to record TSS(measured by hand Refractometer), neck and bulb diameter. Samples of leaves were oven dried at 70 oC, then fine grounded and wetdigested. The nitrogen, phosphorus and potassium contents were determined in dry leaves using the method of Jackson [17], Troug and Mayers[18] and Brown and Lilleland[19], respectively. Data of the two experiments were subjected to statistical analysis of variance according to the procedure outlined by Gomez and Gomez[20]. level of significance. In the second season the interaction had a significant effect on fresh weightof leaves and bulb. The highest fresh weight of leaves and bulb recorded when used potassium in the highest level (200 Kg/fed. as soil application with potassium foliar application). Plant length and leaf number increased with increasing potassium level of soil application and potassium foliar application but this increase faild to reach the 5% level of significance. Total yield and quality: Effect of potassium soil application: Data presented in Table (3) showed that potassium as soil application had a significanteffect on neck diameter, bulb diameter, T.S.S. and total yield. The highest values were recorded when used 200 Kg potassium sulfate per Fed. The results were true in both seasons. The results are accordance with those obtained by Yadav et al[21] who found that the highest potassium rate recorded the highest neck thickness, bulb diameter, bulb fresh weight and bulb yield[26-28] . Effect of potassium foliar application: Results in Table (3) indicated that potassium foliar application had a significant effect on neck diameter, bulb diameter and total yield but T.S.S. faild to reach the 5% level of significance. The highest values of total yield (15.23 and 15.17 ton/fed.) were recorded with potassium foliar application in the two seasons. These results were coincided with those by Abdel-Ati[14], Agwah and Mahmoud [15], Youssef et al[16]. RESULTS AND DISCUSSIONS Growth characteristics: Effect of potassium soil application: Data presented in Table (2) clearly showed that potassium as soil application had a significant effect on vegetative growth characters i.e plant length, number of leaves and fresh weightof leaves and bulb. The highest vegetative growth characters were recorded with soil application of 200Kg potassium sulfate/Fed. In the two seasons. The obtained resultswere in a good accordance with those recorded by Singh and Singh[5], Naidu et al[6], Yadav et al[21], Shrawan et al[22], Al-Abdulsalam and Hamaiel[23]. Effect of the interaction: The interaction between potassium as a soil or foliar application had no significant effect on neck diameter, bulb diameter and T.S.S. The results showed that the interaction significantly affected the total yield. The highest values of total yield were recorded with 200Kg/fed. as soil application and potassium foliar application, in the two seasons. Effect of potassium foliar application: Potassium foliar application had a significant effect on plant length and fresh weight of leaves and bulb (Table 2), but had no significant effect on leaf number per plant. The positive effect of potassium oxide foliar application on growth parameters may be due to that potassium increased efficiency of the plant for utilization nitrogen which is essential for plant growth as well as other processes related to nitrogen metabolism[24]. Similar results were obtained by Adam et al. [12], Daewesh [13], Hassan [25]. Chemical composition: Effect of potassium soil application: Data in Table (4) reported that leaf and bulb dry weight was significantly influenced by potassium soil application in the two seasons. The heaviest leaf and bulb dry weight was obtained with 200 Kg/fed. potassium as soil application in both seasons. Nitrogen and potassium percentage (Table 5) were significantly affected by potassium soil application but phosphorus percentage failed to reach the 5% level of significancein the two seasons. 200 Kg/Fed. potassium as soil application recorded the highest values of nitrogen and potassiumpercentage. There was no significanteffect between 200 and 150 Kg/Fed. on nitrogen percentage in the first season. Effect of the interaction: Results presented in Table (2) indicated that in the first season fresh weight only was significantly affected by the interaction, but plant length, leaf number and fresh weight of bulb faild to reach the 5% 781 J. Appl. Sci. Res., 2(10): 780-785, 2006 Table 2: Effect of potassium fertilizers on vegetative growth of onion plants during 2003-2004 and 2004-2005 seasons. Treatments 2003-2004 2004-2005 --------------------------------------------------------------------------------------------------------------------------------------Plant No. of Fresh weight (g) Plant No. of Fresh weight (g) length (cm) leaves/plant -------------------------------length (cm) leaves/plant -------------------------------Leaves Bulb Leaves Bulb Soil application of potassium sulfate (Kg/Fed.) 50 Kg 44.25 7.25 22.27 59.23 42.67 7.5 21.82 65.9 ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------100 Kg 53 9.25 38.26 129.72 50.67 8.83 35.81 126.29 ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------150 Kg 54.5 9.5 44.42 134.5 51 9.16 40.52 131.37 ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------200 Kg 59.75 12 67.17 182.33 57.33 10.83 62.78 180.51 ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------LSD at 5% 4.23 2.21 10.91 33.43 5.28 2.01 8.12 20.65 Foliar application of potassium oxide (1g/L) Check 49.75 9.13 37.79 111.55 48.25 9 34.86 110.54 ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------K2 O 56 9.88 48.27 141.34 52.58 9.16 45.61 141.5 ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------LSD at 5% 4.49 NS 6.35 20.82 3.62 NS 6.21 16.72 Interaction Check 40 6 20.64 50.87 40.66 7.33 19.01 52.38 50 Kg K2 O 48.5 8.5 23.89 67.59 44.67 7.67 24.62 79.42 ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Check 52.5 9 35.59 123.19 50.33 9 34.09 122.54 100 Kg K2 O 53.5 9.5 40.92 136.25 51 8.67 37.54 130.05 ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Check 52 10 40.8 114.73 50 9.33 37.13 115.52 150 Kg K2 O 57 9 48.04 154.26 52 9 43.92 147.21 ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Check 54.5 11.5 54.13 157.41 52 10.33 49.21 151.73 200 Kg K2 O 65 12.5 80.22 207.25 62.67 11.33 76.36 209.3 ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------LSD at 5% NS NS 11.28 NS NS NS 12.42 23.43 * Check = water foliar application Table 3: Effect of potassium fertilizers on yield and quality of onion plants during 2003-2004 and 2004-2005 seasons. Treatments 2003-2004 2004-2005 --------------------------------------------------------------------------------------------------------------------------------------T.S.S. Neck Bulb Total yield T.S.S. Neck Bulb Total yield diameter (cm) diameter (cm) (ton/fed.) diameter (cm) diameter (cm) (ton/fed.) Soil application of potassium sulfate (Kg/Fed.) 50 Kg 12.25 1.48 5.1 10.49 11.83 1.53 4.97 10.85 --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------100 Kg 12.25 1.83 6.69 14.01 12.5 1.85 6.59 13.99 --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------150 Kg 13.75 1.93 6.93 15.3 13 1.9 6.82 15.04 --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------200 Kg 13.5 2.23 7.45 17.62 13.33 2.25 7.42 17.27 --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------LSD at 5% 0.59 0.11 1.12 1.33 0.9 0.18 0.5 1.54 Foliar application of potassium oxide (1g/L) Check 12.63 1.78 6.09 13.48 12.42 1.78 6.09 13.41 --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------K2 O 13.25 1.95 6.99 15.23 12.92 1.99 6.81 15.17 --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------LSD at 5% NS 0.15 0.73 1.66 NS 0.17 0.56 1.26 Interaction Check 11.5 1.45 4.35 10.07 11.33 1.43 4.5 10.47 50 Kg K 2O 13 1.5 5.85 10.92 12.33 1.63 5.43 11.22 --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Check 12 1.75 6.58 13.64 12 1.8 6.55 13.84 100 Kg K 2O 12.5 1.9 6.8 14.39 13 1.9 6.63 14.14 --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Check 15 1.8 6.35 13.85 14 1.8 6.4 13.3 150 Kg K 2O 12.5 2.05 7.5 16.76 12 2 7.23 16.78 --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- 782 J. Appl. Sci. Res., 2(10): 780-785, 2006 Table 3: Continued Check 12 2.1 7.1 16.38 12.33 2.07 6.9 16.01 200 Kg K 2O 15 2.35 7.8 18.85 14.33 2.43 7.93 18.53 --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------LSD at 5% NS NS NS 2.15 NS NS NS 2.02 * Check = water foliar application Table 4: Effect of potassium fertilizers on dry weight of onion plants during 2003-2004 and 2004-2005 seasons. Treatments 2004-2005 2003-2004 --------------------------------------------------------------------------------------------Bulb Leaves Bulb Leaves Soil application of potassium sulfate (Kg/Fed.) 50 Kg 7.30 3.02 7.53 2.75 --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------100 Kg 15.75 4.70 16.29 4.46 --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------150 Kg 19.82 4.86 16.65 4.48 --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------200 Kg 23.47 6.07 22.51 5.93 --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------LSD at 5% 4.06 0.97 5.14 1.27 Foliar application of potassium oxide (1g/L) Check 14.78 4.24 13.68 4.13 --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------K2 O 18.39 5.08 17.81 4.68 --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------LSD at 5% 2.55 0.43 3.04 NS Interaction 50 Kg Check 6.16 2.14 5.81 2.28 K 2O 8.44 3.91 9.26 3.22 --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------100 Kg Check 14.68 4.54 14.87 4.38 K 2O 16.83 4.86 17.70 4.54 --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------150 Kg Check 18.55 4.70 15.47 4.21 K 2O 21.10 5.02 17.83 4.75 --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------200 Kg Check 19.74 5.59 18.57 5.65 K 2O 27.21 6.56 26.45 6.21 --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------LSD at 5% NS NS NS NS * Check = water foliar application coincided with those of Adam et al[12], Daewesh [13], and Hassan[25]. Such results were in agreement with the results reported by Geetha et al[10], Nagaich et al[11] who found that uptake of phosphorus and potassium was highest with increasing potassium level. Effect of the interaction: The data in Table (4) reported that the interaction between soil and foliar potassium application had no significant effect on dry weight of leaves and bulb. The interaction between soil and foliar potassium application had a significant effect on nitrogen and potassium percentage (Table 5). The highest values were recorded when use 200 or 150Kg /fed. potassium as soil fertilizer with potassium foliar application. However, phosphorus p ercentage was not significantly influenced by the interaction in the two seasons. Effect of potassium foliar application: The results in Table (4) indicated that, potassium foliar application had a significant effect on dry weight of leaves and bulb in the first season and bulb dry weight only in the second season. However, leaf dry weightin the second season faild to reach the 5% level of significance. The heaviest dry weight of leaves and bulb were obtained by potassium foliar application. Nitrogen and potassium percentage increased significantly with potassium foliar application in the two seasons (Table 5). On the other hand, potassium foliar application had no significant effect on phosphorus percentage in both seasons. The obtained results Conclusion: From the obtained results, it can be concluded that under the same condition, the best treatment for increasing productivity of onion plants is using 200 Kg/Fed. potassium sulfate as soil 783 J. Appl. Sci. Res., 2(10): 780-785, 2006 Table 5: Effect of Treatments potassium fertilizers on chemical composition of onion leaves during 2003-2004 and 2004-2005 seasons. 2004-2005 2003-2004 --------------------------------------------------------------------------------------------N% P% K% N% P% K% Soil application of potassium sulfate (Kg/Fed.) 50 Kg 1.57 0.34 1.65 1.74 0.35 1.67 ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------100 Kg 1.58 0.37 1.70 1.78 0.36 1.72 ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------150 Kg 1.69 0.37 1.75 1.82 0.32 1.73 ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------200 Kg 1.71 0.37 1.80 1.88 0.35 1.75 ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------LSD at 5% 0.03 NS 0.02 0.03 NS 0.01 Foliar application of potassium oxide (1g/L) Check 1.60 0.36 1.69 1.73 0.33 1.70 ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------K2 O 1.66 0.37 1.76 1.87 0.36 1.74 ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------LSD at 5% 0.05 NS 0.04 0.07 NS 0.02 Interaction 50 Kg Check 1.52 0.34 1.63 1.73 0.33 1.68 K 2O 1.61 0.33 1.66 1.75 0.37 1.66 ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------100 Kg Check 1.55 0.37 1.67 1.73 0.34 1.70 K 2O 1.59 0.37 1.72 1.82 0.37 1.73 ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------150 Kg Check 1.64 0.36 1.69 1.68 0.32 1.69 K 2O 1.73 0.38 1.81 1.95 0.31 1.77 ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------200 Kg Check 1.68 0.35 1.76 1.78 0.33 1.72 K 2O 1.74 0.38 1.84 1.97 0.37 1.78 ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------LSD at 5% 0.05 NS 0.02 0.04 NS 0.01 * Check = water foliar application application with the potassium foliar application as a stimulating dose. 5. 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