棉 花 学 报     Cotton Science   2008，20(6)：414-417

Effect of Removal of Early Squares on Verticillium Wilt and Premature Senescence in Bt Transgenic Cotton
ZHU He-qin¹，FENG Zi-li¹，SONG Xiao-xuan¹，JIAN Gui-liang²，LIU Xue-ying¹
（1.Cotton Research Institute of CAAS，Key Laboratory of Cotton Cenetic Improvement，MOA，Anyang，Henan 455000 ，China；2. Institute of Plant Protection of CAAS，Beijing 100094，China）

Abstract：Eight cotton varieties with larger planting area in Huanghe River valley and Changjiang River valley are tested to research that the effect of removal of early squares on cotton Verticillium wilt, early senescence of cotton plant and yield. The result showed that the disease indexes and the early senescence indexes of removal of early squares treat ments are evidently lower than the comparison, Disease index of removal of early squares is evidently lower than the comparison in 18 July, 19 August in 2005 and 22 August in 2006.Except Xinkang 4, disease indexes of the other 7 varieties is lower 1.6% ～ 15.0% than the comparison. Early senescence ID of removal of early squares is also evidently lower than the comparison in 19 August, 24 August in 2005 and 27 August in 2006.Except Han 109, disease index of the other 7 varieties is 1.3% ～ 19.0% lower than those of the comparison. The yield of removal of early squares is evidently higher than the comparison. But different varieties show different effect, the hybridizing varieties are more evident.
Key words：removal early squares; Verticillium wilt; early senescence    [Full Text, 1748KB]