Comparison between aerobic and Iranian rice (Oryza sativa L.) varieties and genotypes to drought stress tolerance at germination stage

Introduction  One of the most important variables for establishment of the appropriate rice seedling under stress environments is high power of the germination and emergence. In this regard was conducted a research to study of genetic variation in aerobic rice and Iranian genotypes on the base of tolerance to drought stress. Material and methods Seed germination test was conducted in three levels of osmotic stress (distilled water, -8 and -16 bar of manitol) and 52 rice genotypes as a split plot in a randomized complete block design with three replications. Genotypes consisted of 31 genotypes of the aerobic rice and foreign as well as 21 Iranian varieties of rice. Results The results showed that there were significant difference between osmotic stress levels, genotype and interaction between the levels of osmotic stress and genotypes for whole germination components. Considering all of above condition, the highest ranks in the overall comparison to Arunachalam method were belonged to genotypes aerobic and foreign named AE8, AE6, AE18, AE16 and AE29 and lowest ranks were for Iranian genotypes named Ghasroldashty, RashtiSard, Anbarbou, AliKazemi, Champabodar, Hashemi and DomSiah. Conclusions According to these results, foreign and aerobic genotypes showed relative superiority more than Iranian rice on the base of the characteristics of germination and with increasing levels of drought stress; foreign and aerobic genotypes were more tolerant.