Study on Morphological Traits, Cooking Quality and Yield Stability Analysis in some Rice Genotypes

Eight rice genotypes with two checks (Dasht and Nemat) were evaluated in three locations of Mazandaran province for two years (1999-2000), in a RCBD with four replications. This study was carried out to determine the qualitative and morphological traits and yield stability to select the best genotypes. The results of combined ANOVA showed significant differences among genotypes. The effects of location, year, genotype×location and genotype×year were not significant. The interactions of year × location, and year×location × genotypes were significant that proved the existence of interaction between genotype and environment. Grain yield stability using ten different methods, showed that Nemat cultivar (genotype 7310) with less variance (S2i) and coefficient of variability (CVi) of environment, less coefficient of regression of mean yield on environmental index (bi) and variance of deviation from regression linear (S2di), was the most stable genotype. Genotype 7304 having bi equal to unity, less S2di and high yield, was the most stable genotype. There were no significant differences between the mean yield of genotype 7304 and genotypes 7302, 7303, 7305 and 7306. Regression line slope of these high yielding genotypes was equal to unity too. Therefore they had high general adaptability. Nemat cultivar and genotype 7305 with less mean and standard deviation of ranking ( , S.D.R) and genotypes 7304 and 7303 based on Wricke, s equivalence (Wi2) and Shukla, s stability variance (σ2i), had the highest stability, respectively. The cooking quality of genotypes 7302, 7304, 7306, 7307 and 7308 was excellent with intermediate amylose content and gelatinization temperature. Consequently the genotypes 7304 and 7302 having higher mean yield compare to Dasht, and desired cooking quality and morphological traits were selected as elite genotypes.