Evaluation of yield stability of Virginia tobacco hybrids using stability parameters and pattern analysis via AMMI model

To determine the yield stability, adaptability and analysis of the genotype× environment interaction of Virginia tobacco, 15 hybrids of tobacco including 10 Iranian and 5 international hybrids were evaluated in two different experiments (water stress and normal irrigation) using a Randomized Complete Block Design (RCBD) with three replications at two locations including Rasht and Tirtash Tobacco Research Centers (four environments) for two years (2006 to 2007). Statistical methods including combined analysis of variance, estimating 14 stability parameters and pattern analysis were applied. Result of environmental variation and coefficient of variance showed that hybrids Coker254                         VE1, K394 VE1 and NC89 VE1 had low value for environmental variance and coefficient of variation was the most stable genotypes, respectively. The hybrid PVH03 based on Shukla^'s stability variance, Wricke^'s equivalence, variance of deviation from liner regression and also interaction principal component analysis axis 1(IPCA1) of AMMI model was known as the most stable hybrids. The biplot technique was used to identify appropriate genotypes to special locations. Results showed that hybrids PVH03, K394 NC89 and Coker254 NC89 with the lowest interaction, and hybrids ULT109, NC291, Coker254 Coker347 and VE1 Coker347 with the highest interaction were the most stable and unstable hybrids, respectively. Furthermore, hybrids Coker254 K394, NC291 and CC27 for Tirtash and hybrids NC89 Coker347, K394 Coker347, Coker254 VE1 and ULT109 for Rasht were more suitable in non drought stress condition.