Selection parameters for grain yield and its components in rainfed wheat (Triticum aestivum)

Genotypic and phenotypic correlation coefficients for 13-traits in rainfed wheat were studied. A significant and positive genotypic association for grain yield with germination per cent (0.339%), grains ear⁻¹ (0.354), 1000-grain weight (0.361 g), total biomass (0.612 g), specific leaf weight (0.423) was observed. These traits had positive association at phenotypic level also. However, at environmental level seed yield showed negative relationship with 1000-grain weight but showed positive association with plant height, biomass and harvest index. Germination per cent, low seedling mortality, plant height, 1000-grain weight, total biomass production, harvest index and specific flag leaf weight seemed to be associated with stabilizing grain yield potential in response to nitrogen levels under rainfed condition. Therefore, these relatively simple traits can be used as selection criteria to screen large number of wheat germplasm for drought tolerance.