Genetic Diversity of Rice Germplasm under Flooding and Drought Stress

Due to the importance of increasing the yield and complexity and the effect of this trait on environmental impacts and lack of water resources, the present study aims to study the relationship between yield and its components, analysis of correlation coefficients between traits and determination of the most important traits in rice yield in two conditions without stress and Drought stress was used to identify the effective indices for improving the grain yield of rice on foreign rice germplasms in two different conditions in the Latis design at Gonbad-e-Kavas University. The results of analysis of variance showed that there is a significant difference between genotypes for all traits. A simple correlation between traits showed that grain yield in irrigated condition had the highest positive correlation with grain weight trait and then with main panicle weight trait. In drought stress condition, grain yield had the highest correlation with filled grain weight, filled grain number and harvest index. In order to investigate and determine the causal relationships of traits entered into the regression model with each other and with the yield s, path analysis was performed and it was determined that the highest direct and positive effects on grain yield in irrigated and stress conditions were related to the grain weight. Cluster analysis, the Ward method was categorized genotypes into four distinct groups in both conditions without stress and stress. In this research, two traits of filled grain weight and number of fertilized tillers had the highest direct relation and the lowest negative correlation was obtained through other traits with grain yield. Therefore, these two traits can be introduced as an indirect selection criterion for grain yield.