Abstract: Bio-assays and tissue section examinations were conducted for determining the resistance of transgenic poplar(Populus deltoides,1-63×1-69)expressing Bt CrylA toxin to Clostera anachorta.The results showed that larvae fed with the transgenic poplar leaves showed increasing mortalities and weight inhibition rates with the extension of exposure period,being 10%and 6.85%at 2 d,48.33%and 27.93%at 4 d,and 81.67%,63.03%at 10 d,respectively. Pupation rate of larvae fed with non-Bt and Bt transgenic poplar for 12 d was 100%and 18.18%,respectively.The midgut epithelium cell of the larvae exposed to transgenic popular was loose and partially vacuolar,and the cell boundary was vague.It is suggested that the transgenic Bt poplar shows insecticidal and growth-inhibitory effects on C. anachorta.
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