Effect of foliar application of ascorbic acid (vitamin C) on yield and yield components of corn (Zea mays L.) as influenced by withholding of irrigation at different growth stages

In order to study the effect of ascorbic acid foliar application and limited irrigation on quantitative and qualitative characteristics of corn, an experiment was conducted in research field of Islamic Azad University, Varamin Branch in Iran during 2012 growing season. The experimental design was laid out in a randomized complete, block with a split plot arrangement of treatments in three replications. Main plot included four different levels of irrigation (complete irrigation, irrigation withholding at 8-leaf stage, irrigation withholding at silks appearance stage and irrigation withholding, at both 8-leaf stage and silks appearance stages) and different concentration of foliar application of ascorbic acid (vitamin C) (0, 75 and 150 ppm) was allocated to sub-plots. The results showed that irrigation withholding conditions in different growth stages significantly decreased plant height, yield components, seed yield, biological yield, harvest index, oil and protein percentage and oil and protein yield. Ascorbic acid foliar application in irrigation withholding in different growth stages had positive effect on all attributes in this experiment. In general, the results of the present study indicate that usage of AsA reduces the harmful effects of water deficit stress and increases resistance to drought stress in corn plant.