Estimation of Heterotic Performance and Inbreeding Depression for Grain Yield and Contributing Traits in Bread Wheat (Triticum aestivum L.)

The present investigation was conducted Student Instruction Farm at Chandra Shekhar Azad University of Agriculture and Technology, Kanpur, during the rabi season of 2022–2023. 10 diverse wheat cultivars viz., DBW 88, K 9006, DBW 187, WH 1142, HI 1563, HD 3326, K 9423, K 1317, KRL 210 and KRL 19. Each parent and F1 were planted in single row while each F2 was planted in two rows of three meter length with inter and intra-row spacing of 22.5 cm and 10 cm, respectively. Observations were recorded on plot basis for days to 75% flowering and days to maturity while plant height, number of effective tillers per plant, spike length, number of spikelets per spike, number of grains per spike, Biological yield per plant, grain weight per spike, grain yield per plant, 1000 grain weight, Harvest index, Protein content and Seed hardness were recorded on 5 randomly selected plants. In breeding programme for the development of wheat varieties, indigenous, exotic and wild species germplasms are the backbone of successful breeding programme for improving yield and yield contributing characters. The minimum and maximum value of economic parent (DBW 187) heterosis for grain yield plant-1 varied from -36.53 to 16.31 (HI 1563 x K 9423 to DBW 187 x K 1317) per cent. Eight crosses showed positive and significant heterosis, out of these, five in order of merits were, DBW 187 x K 1317, DBW 88 x DBW 187, K 1317 x KRL 210, DBW 187 x KRL 19 and DBW 187 x HI 1563 while thirty seven crosses showed negative and significant in economic heterosis for grain yield plant-1. Grain yield plant-1 noted inbreeding depression from -0.10 to 19.24 (DBW 187 x KRL 210 to K 9423 x KRL 19) per cent. Thirty one crosses observed positive and significant while no any cross found for negative and significant inbreeding depression for grain yield plant-1.