Standard Heterosis for Seed Cotton Yield and Component Traits in Upland Cotton {Gossypium hirsutum L.)

摘要

Cotton being an often cross pollinated crop is amenable for heterosis breeding. In cotton, there are two main pre-requisites for commercial exploitation of heterosis viz., identification of parents which show high magnitude of heterosis on crossing and production of hybrid seed with minimum cost. Hence, the present investigation was planned to study standard heterosis in 52 cotton hybrids. The experimental material comprised 48 hybrids along with four checks (RCH-2, RAHH-95, Bunny Bt and DHH-11). Thehybrids were produced by crossing 14 new intra-hirsutum lines (8 lines 6 testers) which were isolated from new heterotic pools of segregating generations of multiple crosses in line x tester fashion during kharif2007-08. These hybrids were grown in randomized block design with two replications during kharif2008-09 atAgricultural College Farm, Bapatla. Each genotype was sown in three rows of 4.2 m length with inter- and intra-row spacing of 120cm 60cm in each replication. Data on plot basis or 10 randomly selected plants in each hybrid per replication were collected for plant height, days to 50% flowering, number of monopodia plant1, number of sympodia plant1, number of bolls plant1, boll weight, seed index, lint index, ginning out-turn, 2.5% span length, micronaire value, bundle strength, uniformity ratio, fibre elongation, lint yield plant1 and seed cotton yield plant1. The standard heterosis was calculated as per cent increase or decrease observed in F1 over standard check as per Liang eral. (1972).