Role of Application Method in Responses of Cotton Plants to Micronutrients and Potassium Humate

Abstract

Afield experiment was carried out in a clayey textured soil (Clayey, Smectitic, Superactive, Mesic, Typic) located at Sakha Agricultural Research Station farm, Kafr El-Sheikh Governorate, Egypt (30o 56 N latitude and 31o 05 E longitude) to study the effect of different application methods (foliar fertilization and seed coating) with mixture of some micronutrients (Fe, Mn, Zn) and potassium humate on cotton Giza CV 94 during summer seasons of 2015 and 2016. A split plot design was used with three replicates. The main plots were assigned with three application methods: foliar application, seed coating and (foliar + seed coating). The sub plots were assigned with three treatments of Micronutrients, potassium humate and mixture of (micronutrients + potassium humate) in addition to the control treatment. The obtained results can be summarized as follow:- Plant height and number of fruiting branches were increased by (spraying + seed coating) method during the two seasons. Meanwhile the fertilizer treatment of (micronutrients mixture + potassium humate) significantly increased plant height (cm) and number of fruiting branches.plant-1. Foliar spraying + seed coating treatment gave the highest values of number of open bolls, boll weight, seed index and seed cotton yield. fed-1., compared with the other two application methods. Plants sprayed or coated with mixture of (micronutrients + potassuim humate) caused a significant increase in number of bolls.plant-1, boll weight and seed index. Mix of (micronutrients + potassuim humate) produced the highest significant values of seed cotton yield.fed.-1, but untreated plants gave the highest values of earliness in the two season compared with other treatments. The highest values of the fiber fineness were obtained by spraying plants with mixture of (micronutrients + potassium humate). On the other hand, coating seeds with (micronutrients + potassium humate) gave the highest values of fiber strength. Mixture of (micronutrients + potassium humate) increased the concentrations of N, P, K, Mn, Zn and Fe in cotton last mature leaves. Also, the highest values of N, P, K, Mn, Zn and Fe in cotton last mature leaves were obtained when (seeds coating and foliar) was used with mixture of (micronutrients + potassium humate).