Genetic architecture of Morpho-Physiological and biochemical characters associated with drought tolerance in bread wheat (Triticum aestivum L.)

A field experiment comprising eight genetically diverse bread wheat varieties i.e., five drought tolerant (PBW 175, RSP 81, PBW 500, K 9943 and HUW 576) and three drought susceptible (RSP 312, RSP 303 and WH 542) was conducted during rati 2003–04 and 2004–05 at the experimental area of Division of Plant Breeding and Genetics, Sher-e-Kashmir University of of Agricultural Sciences and Technology, Jammu. These cultivars were crossed in all possible combinations to produce twenty eight crosses (excluding reciprocals). Hybrids along with parents were evaluated for various morpho-physiological and biochemical determinants under normal (E₁) and moisture-stress (E₂) environments. Both additive and dominance components of variance were significant for most of the traits under study in both E₁ and E₂. Significance of non-additive genetic components was indicated by number of tillers per plant, spike length in E₂ and proline content in both E₁ and E₂. However, the additive genetic component was predominant in all other characters. To exploit both additive and non-additive gene action, reciprocal recurrent selection and diallel selective mating approaches are suggested.