Effect of Skipping Irrigation at Different Growth Stages and Zinc Foliar Application on Yield and Water Productivity of Sunflower

Abstract

An experiment was conducted at the Experimental Farm of Sakha Agricultural Research Station 31° 07\\ N and 30° 57\\, Kafr El-Sheikh, Egypt, during 2015 and 2016 seasons to study the effect of skipping one irrigation at different growth stages and foliar application of zinc on quantitative and qualitative characteristics of sunflower cultivar Sakha 53.A split plot design with four replications was used. The main plots were devoted to water treatments i.e. I 1 = without skipping (control four irrigation during season), I 2 = skipping one irrigation during vegetative stage, I 3 =skipping one irrigation during flowering stage, I 4 = skipping one irrigation during grain filling stage. Sub plot treatments were devoted to foliar application with zinc sulfate , i.e. Zn o = water application, Zn 1 = 0.5% and Zn 2 = 1% concentration. The results showed that flowering stage was the most sensitive to water deficit stress and skipping irrigation at this stage caused marked decrease in chlorophyll content in leaves, relative water content (RWC %), seed oil %, seed yield and its components, while increased proline content and seed protein % in the two growing seasons. Zinc spraying had significant effect on all attributes in this research. In general, application of Zn could be used as a good tool to increase yield of sunflower under drought stress.Also, the highest mean values for seasonal amount of water applied and water productivity were recorded under traditional irrigation. From this study we can be concluded that it is possible to gain high seed yield with less quantities of applied water when the irrigation skipping happens at vegetative stage with application of 1% zinc sulfate .