陆地棉族系种质系与陆地棉品种间的杂种优势利用研究

Heterosis in Upland Cotton:Useness of Breeding Lines Developedfrom Primitive Race Stocks(Gossypium hirsutum L.)

采用ＮＣⅡ（ＮｏｒｔｈＣａｒｏｌｉｎａⅡ）交配设计选用６个陆地棉族系种质系材料和３个常规品种组配１８个Ｆ１，对杂种及亲本进行比较研究，研究陆地棉族系种质系在杂种优势中的利用价值。研究结果表明，产量杂种优势表现明显，皮棉产量优势最大，其余依次为子棉产量、铃数、单铃种子数、单铃重。纤维品质优势表现软弱。试验表明产量杂种优势主要来源是铃数、单铃种子数、铃重增加。研究还发现亲本间遗传距离与杂种优势关系不明显；特殊配合力效应与优势率显著相关。

Studies were made on heterosis in F1 hybrids bettween three cultivars and sixbreeding lines.The breeding lines were developed via backcrossing different primitive racestocks of cotton(Gossypium hirsutum L.)with commercial upland Cotton as recurrent parents.The result showed the heterosis for yield and fiber properties were obvious. The mid parentheterosis was the largest for lint yield with an average of l8%. Seed cotton yield was the sec-ond(7.93%).The mid一parent heterosis for number of bolls,seeds/boll, boll weight, lintpercentage,and lint index was 5.65,3.64,2.92,1.70 and 0.20%,respectively. Heterosisfor fiber properties were relatively small.The genetic distance was not related to the heterosis.The heterosis of F1 hybrids in net photosynthesis rate was signifcant in peak square stage.