study of seed yield stability in winter rapeseed (brassica napus) genotypes using eberhart and russell’s method

in order to study the seed yield stability of oilseed rape lines, a series of experiments were carried out at karaj, kermanshah, tabriz, hamedan and arak agricultural experiment stations using 10 lines, two control varieties of winter rapeseed and 3 promising lines (a total of 15 genotypes) in randomized complete block designs with three replications for two cropping seasons (2009-11). analysis of variance showed that there was significant differences among genotypes in different environments in terms of yield. combined anova revealed significant interaction of genotype×year×location. the lines l183, hw101, sw101, karaj1, karaj2 and sw103 with seed yields 4.647, 4.595, 4.556, 4.443, 4.441 and 4.306 (t/ha) respectively, were better than overall mean and had lower ranks and rank variance than others. eberhart and russell stability analysis method showed significant differences between genotypes for grain yield. environmental variance (linear) was significant and showed a linear relationship between the genotypes in each environment with the environmental index. genotypes l183, sw101, sw103, hw101, karaj1 and karaj2 with highest yield, coefficient of regression equal to unity and non-significant deviation from regression line were the most stable genotypes. therefore, these genotypes can be used in further studies and eventually for cultivation in cold and mild cold regions.