Heterosis were determined in 33 F1 hybrids, their F2 generations and parental lines for growth period, plant height, first section height, first section position, fruit branches per plant, yield components and fiber quality parameters.The results show that there was significant difference in heterosis value for specific character both among crosses and between generations.The percentage of crosses with negative heterosis on growth period and plant height in all F1 and F2 generations reached 60.61％ and 57.58％, 84.85％ and 84.85％, respectively.The percentage of crosses with positive heterosis on first section height, first section position, fruit branches per plant, bolls per plant, boll weight, lint percentage, and fuzz length in all F1 and F2 was 16.67％ and 21.21％, 24.24％ and 51.52％, 1.52％ and 3.03％, 7.58％ and 21.21％, 50.00％ and 19.70％, 31.82％ and 24.24％,53.03％ and 42.42％, respectively.The heterosis values on yield components was boll weight＞lint percentage＞ bolls per plant.It indicated that yield improvement in cotton hybrids is mainly not due to increasing of bolls per plant, but boll weight.The results of over-standard heterosis analysis show that 7 from 33 crosses with better comprehensive performance.The seed cotton yield and lint yield of 13 F1 hybrids were higher than that of CK at least by 10％.Higher over-standard heterosis on seed cotton yield, lint yield and fuzz length in 08-296 × 08-377 F1 and F2 generations indicated that improvement of both yield and fiber quality synchronously could be realized.%用不同来源田间表现优良的棉花品种(系)按照性状互补原则配制33个杂交组合,通过双亲、F1、F2代的9个性状相互比较,探讨不同世代及不同性状的杂种优势,并筛选优良组合.杂种优势分析结果表明,同一性状的杂种优势在不同组合、不同世代间存在较大差异;F1、F2代的生育期、株高存在负向杂种优势的组合分别有60.61%和57.58%、84.85%和84.85%;F1、F2代的始节高、始节位、果枝数、单株铃数、单铃质量、衣分、绒长存在正向杂种优势的组合分别有16.67%和21.21%、24.24%和51.52%、1.52%和3.03%、7.58% 和21.21%、50.00%和19.70%、31.82%和24.24%、53.03%和42.42%;产量构成因素杂种优势强弱顺序为单铃质量＞衣分＞铃数,说明杂交棉增产的主要原因足铃质量的增大,而不是铃数的增多.超标优势分析结果表明,有7个组合综合表现优良;有13个组合F1代的籽棉和皮棉均比对照增产10%以上,其中有6个组合比对照增产30%以上;并且组合08-296×08-377的F1、F2代产量和绒长均具有较高的正向超标优势,说明杂交棉有望实现产量和品质的同步提高.
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