Effect of Interaction Between Water Stress and Foliar Application by Ascorbic Acid or Micronutrients on Maize Productivity and Irrigation Water Use Efficiency

Abstract

Two field experiments were conducted in a new soil in extention field in El Qantra-West, Ismailia Governorate, Egypt during 2017 and 2018 summer seasons. The study aimed to evaluate the effect of six exogenous application levels of ascorbic acid (AsA) and micronutrients mixture on yellow corn hybrid 352 (three way cross) under three amounts of irrigation water (3750, 3000 and 2250 m 3 /fad., of the estimated crop evapotranspiration) using surface irrigation system. A randomized complete block split plot design with three replicates was used in each season. The irrigation treatments and the levels of AsA and micronutrients mixture were randomly allocated in the main and sub-plots, respectively. The most important findings could be summarized as follows. Decreasing the amount of irrigation water from 3750 to 2250 m 3 /fad., significantly diminished ear leaf blade area, relative water content and total chlorophyll at 85 days from sowing. Also, at harvest, ear length, 100-grain weight and grain yield/fad., were decreased, but irrigation water use efficiency (IWUE) was significantly ameliorated. Generally, foliar application by AsA or micronutrients mixture significantly increased these traits with increasing irrigation water use efficiency (IWUE) compared with their untreated analogues. The interaction between both studied factors showed that 350 ppm AsA treatment protected about 500 kg/fad., grains from collapse under moderate and severe water stress. Application of AsA saved approximately 750 m 3 /fad of irrigation water without yield reduction under stress conditions.