Effect of genome combinations on stability of yield and yield components in wheats and triticales.

The data on number of grains/spike, 100 grain weight and grain yield/plant in eighteen genotypes of four genome combinations (AABB- 4 genotypes, AABBDD- 6 genotypes, AABBRR- 5 genotypes and AABBDDRR- 3 genotypes) were recorded for eight environments created by combining two dates of sowing, two fertilizer regimes and two spacings. Two stability parameters-regression coefficient (b) and deviation from regression (Sd (2)) were computed. Joint regression analyses revealed that the genotypes differed significantly for these characters. A significant variation due to environments was also found. A comparative study of performance of genotypes belonging to four genome combinations revealed that the genes for stability are not uniformly distributed in these genome combinations. Stability may largely depend on gene combination rather than on genome combination.