Influence of defoliation as a source restriction factor and late-season water stress on grain corn (Zea mays L.)

ABSTRACT: In order to study the effect of water deficit stress on morphological traits, yield and yield components of grain corn (Zea mays L.), a field experiment was laid out as a split-plot based on a randomized complete block design with three replications. The main plot included defoliation at seven levels (removal of cab leaves, upper leaves of cab, lower leaves of cab, tassel, three upper leaves of cab, three lower leaves of cab, and control) and the sub-plot was irrigation at four levels (no irrigation and irrigation interval at three levels of 6, 12 and 18 days). The results showed that remove upper leaves of cab significantly decreased the grain number, grain number in row, row number in cab, dry weights of cab skin, cab stem, cab wood and stem length of cab compare with other treatments. Moreover, it was found that all characteristics significantly decreased with increasing water stress severity as the highest amount was found in 6 days interval irrigation.