棉 花 学 报 Cotton Science 2006，18(5)：304-308
Combing Ability and Heterotic Performance of Bt Transgenic Lines in Cotton (Gossypium hirsutum L.) Abstract：Five transgenic lines of cotton (Gossypium hirsutum L.) carrying the cry1Ac (Bt，Bacillus thuringiensis) gene were developed from a cultivar JH321 by independent transformation events. Fifteen F 1 hybrids were obtained from diallel crosses among the five transgenic lines and JH321. When compared with the transformation receptor cultivar JH321，significant variations in agronomic traits including improved yield or yield components were found among these transgenic lines. General combining abilities (GCA) among these transgenic lines varied greatly，and two such lines with significant positive GCA effects were identified. Heterosis in F1 hybrids also exhibited significant variations. It was found that the average heterosis of crosses with two transgenic lines was lower than that with only one transgenic line as parent in yield performance. The economic trait improvement for transgenic lines and the heterosis produced between transgenic line and receptor cultivar might be raised from different integration sites of Bt gene.
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