Field performance of maize (Zea mays L.) cultivars under drought stress

<p>This research was carried out in 2014 at the Research Farm of the University of Tabriz, Iran. The experiment was arranged as split plot on the basis of randomized complete block with three replicates to assess the effects of four irrigation intervals (irrigations after 60, 80, 100 and 120 mm evaporation) on physiological and agronomical traits of three cultivars of maize (<em>Zea mays </em>L.; ‘SC704’, ‘NS640’, ‘DC303’: late, mid and early maturing, respectively). Irrigation intervals and maize cultivars were assigned to the main and sub-plots, respectively. Leaf temperature of all maize cultivars significantly increased, but chlorophyll content index, maximum efficiency of photosystem II, number of grains per plant, 1000 grain mass, plant biomass, grain yield and harvest index significantly decreased with increasing irrigation intervals. Late maturing cultivar (‘SC704’) was superior in all studied traits, followed by mid (‘NS640’) and early (‘DC303’) maturing cultivars. It was concluded that water limitation can potentially reduce performance of maize cultivars in the field, but the extent of this reduction depends on genotype and severity of stress.