Effect of Terminal Drought on Morphologic Attributes and Grain Yield of Nine Rice Cultivars and Lines

The aim of this research was to determine the effect of terminal water stress (arranged in main plots) on nine cultivars and promising lines (arranged in sub plots) regarding grain yield and morphologic attributes in Miyaneh, Iran. A split plot experiment was conducted based on randomized complete blocks with four replicates. Results showed that there were significant differences among genotypes for grain yield in both conditions. Drought affected adversely tiller number, panicle number, grain and 1000 grain weight and grain yield. No significant genotype*drought interaction was observed for the traits under study. Stepwise regression showed that panicle number and grain number per panicle were significantly related to grain yield. Hashemi and Local 1 had greater plant height than the mean but produced the lowest grain yield in both conditions. On the other hand, Saleh and 830 which had lower plant height were high yielding. Hassansarayi, 830, 841, Saleh and Local 2 produced higher grain per panicle and grain weight per plant, but Hashemi and Local 1 showed lower grain per panicle, grain weight per plant and consequently lowest grain yield. Saleh and 830 were found to be the most tolerant genotypes in this study.