Study of genotype x environment interaction in rice (Oryza sativa L.) by stability estimates

Twenty genotypes of late maturing group of rice were tested at four different locations in randomized complete block design (RCBD) with two replications to compare the stability estimates methods of Wrick’s ecovalence, Shukla stability variance, Tai α and λ of stability analysis along with Eberhart and Russel model using Spearman’s rank correlation coefficients. The results indicated that the sum of squares for genotype x environment interaction (GEI) was found significant. All the three components i.e. environment (Lin.), G x E (Lin.) and pooled deviations were found highly significant and accounted for 86.8, 7.9 and 5.2 per cent of sum of squares, respectively. Genotypes NWGR-3006, IET19140, IET19123, IET19147 and IET19160 were found stable, high
yielding genotypes adaptable to all the environments. Genotype IET19146 was stable and well adaptable to favorable environment. According to Wricke’s ecovelence and shukla’s stability variance, genotypes IET19147, NWGR-3006, IET19114, NWGR-3113 and NWGR-3213 were considered to be the most stable.Genotype IET19143 due to its higher ecovalence and shukla’s stability variance was considered as most unstable genotype. The genotypes namely NWGR-3113, NWGR-3006, IET19147 and IET19114 were located in the average stability region and NWGR-3213 into the above average stability region. IET19132 and IET19143 were highly unstable in performance as it had highest λ value. The rank correlation coefficient between bi-Eber and Tai’s α were perfect positive and also positive perfect correlation was observed between Wi 2 and Sh-σ 2. S2 di had positive and high rank correlation with Wi2, Sh-σ 2 and Tai λ. The stability estimates Wi2, Sh-σ 2, Tai’s α and Tai’s λ would be used in place of Eberhart and Russel model. According to all methods, genotypes IET19147 and NWGR-3006 were identified as high yielding and stable genotypes.