Evaluation of Yield Stability Promising Lines of Rice (Oryza sativa)

Determining new and higher and stable yielding varieties is one of the most important objectives of rice breeding. To achieve this goal, ten promising lines of rice along with two improved cultivars (Hashemi and Kadous) were compared at National Rice Research Institute in Rasht, Iran, for three years (2006, 2007 and 2008). The experimental design was randomized complete blocks with four replications in these three years. The combined analysis of variance indicated significant difference among genotypes, for the traits studied. This indicates genetic variation among genotypes understudy. The interaction of genotype × year for yield was significant which demonstrate different responses of genotypes during different years. Different stability analysis methods were used to determine the higher and stable yielding variety like: environmental variance, coefficient of variability, coefficient of regression proposed by Finaly and Wilkinson, Deviation from regression by Eberhart and Russel, Shukla's stability variance, Wricke's equivalence, coefficient of determination of Pintus and non-parametric method of rank. By using these analyses it was found that Hashemi was a stable yielding variety. It was also revealed that line No. 9 (IR78530-45-3-1-3), line No. 6 (IR76993-49-1-1) and 8 (IR78533-30-2-1) were found as stable producer lines.