Heterosis for yield and associated traits in bread wheat [Triticum aestivum (L.) em. Thell.].

摘要

An experiment was conducted on bread wheat cultivars Raj 3777, Raj 3765, Raj 3077, PBW 373, Raj 1482, HD 2329, WH 14 and Lok 1, and their 28 F1s generated by diallel mating to estimate the magnitude of heterosis under normal (N, 12.9-32.4 degrees C) and heat stressed (HT, 8.6-26.3 degrees C) environment. Data were recorded for days to heading, days to maturity, number of effective tillers per plant, plant height, spike length, number of spikelets per spike, number of grains per spike, flag leaf area, 1000-grain weight, biological yield per plant, harvest index and grain yield per plant. The analysis of variance revealed highly significant difference among the parental material for most of the characters in different environments as well as over environments, indicating the presence of sufficient heterosis. In general, there was negative heterobeltiosis for yield under normal environment, while it was reversed under HT environment. Raj 3765 x HD 2329 was superior compared to other promising crosses as it showed better performance for most of the characters under both environmental conditions.