Selection Indices for Seed Yield in Indian Mustard (Brassica Juncea (L.) Czern & Coss), I. Based on Physiological Attributes

Selection indices based on the relative importance of four physiological attributes were used in non-segregating populations of two crosses of Indian mustard, namely RH 30 × RC 781 and Prakash × RC 1425. It was observed that leaf area duration and leaf area index at reproductive phase, when selected simultaneously, resulted in the highest genetic gain in seed yield. Selection indices based on leaf area duration and leaf area index exhibited superiority over straight selection for yield in both crosses. However, leaf area duration combined with any other character satisfactorily improved the expected genetic gain in both crosses. The genotypes having persistent green leaves till physiological maturity reflected long leaf area duration, hence selection for tins physiological attribute at this stage would be desirable for seed yield improvement in this crop.