Impact of Drought Stress on Vegetative Growth and Grain Filling Stages: Morphological Traits and Yield Components of Six New Corn Hybrids in Iran

This study investigates the impact of drought stress on various agronomic traits of corn hybrids, highlighting the physiological responses and yield performance under water-limited conditions. Conducted in Shush County, Iran, the experiment utilized a split-plot design with four replications. The primary factors included three irrigation levels: normal irrigation, drought stress from emergence to tassel appearance, and drought stress from the end of pollination to physiological maturity. The secondary factors were seven corn hybrids, including six new hybrids and the control variety, SC704. The results revealed that drought stress, particularly during the vegetative growth period, significantly reduced the growth duration, leaf area index, biological yield, and grain yield. One of the hybrids, labeled as H4 demonstrated the highest resilience, maintaining superior biological yield, grain yield, and leaf area under drought conditions. These findings underscore the importance of selecting drought-tolerant hybrids for cultivation in regions prone to water scarcity. Future research should incorporate additional abiotic stresses to develop a more comprehensive understanding of the corn hybrids’ performance in diverse environmental conditions.