陆地棉棉铃性状的杂种优势研究

用多元回归和灰色关联度分析的方法 ,研究了 3 0个陆地棉杂交组合棉铃性状的杂种优势及其与铃重杂种优势的相关性。结果表明 :( 1 )陆地棉品种间 F1的棉铃性状具有较强的杂种优势 ,单铃重、单铃种子数、铃容重和结子效率的竞争优势较大 ,分别为 2 5. 70 %、 1 7. 58%、 1 6 . 6 9%和- 1 3 .6 1 % ,而中亲优势以单铃种子数、结子效率、单铃重和铃容重居前 ,分别为 1 1 .93 %、7.73 %、5.1 4%和 - 1 0 .56 %。 ( 2 )铃容重、铃体积和单铃种子数的偏相关系数为达极显著水平 ,在竞争优势和中亲优势中 ,三性状的合计相对决定度分别占总决定度的 6 9.0 6 %和 71 .0 7%。 ( 3 )用逐步回归分析法找出了影响铃重杂种优势的三个主要性状 ,按其直接效应大小依次为铃容重 >铃体积 >单铃种子数。单铃种子数通过铃容重和铃体积对铃重的间接效应较大 ,故其净效应居首位。 ( 4 )根据灰色关联度排序 ,对铃重杂种优势影响最大的因子是单铃种子数的杂种优势 ,其它影响较大的性状依次为结子效率 >铃容重 >铃体积

Studies on Heterosis of Boll Traits in Upland Cotton

The correlation between the heterosis of boll traits and that of boll weight was studied through stepwise regression and grey relational analysis with 30 upland cotton combinations and their parents. Experimental results showed: (1) Heterosis of intraspecific hybrid F 1 boll traits in upland cotton was obvious. The useful heterosis was significant for boll weight, seeds per boll, boll density and motes per boll with the average of 25.7, 17.58,16.69 and 13.61% respec tively vely. The mid parent heterosis mean value of seeds per boll, boll weight, boll density and motes per boll was 11.93,7.73,5.14, 10.56%, respectively. (2) The partial correlation coefficients of boll density, boll volume and seeds per boll were extremely significant. Their total relative determinative degree for check and mid parent heterosis took up, respectively, 69.06% and 71.07% of all. (3) Boll density, boll volume and seeds per boll were three dominant factors assessed by their direct effects on the heterosis of boll weight. However, the net effects of seeds per boll were the most remarkable, due to its indirect effects via boll density and boll volume. (4) The results of grey relational analysis indicated that seeds per boll was the hegemonic factor to the heterosis of boll weight, followed by motes per boll, boll density and boll volume.