【摘要】 采用生物测定方法测定茶尺蠖核型多角体病毒(Ectropis obliquanuc leopolyhedrovirus,EoNPV)和苏云金杆菌(Bacillus thuringiensis,B t)的联合作用。5组不同含量EoNPV制剂(1.50×107PIB/m l、1.25×107PIB/m l、1.00×107PIB/m l、7.50×106PIB/m l和5.00×106PIB/m l)中混合2 000 IU/mg B t制剂后共毒系数在106.02至128.03之间,表明B t与EoNPV混用具有增效作用。其中以1.00×107PIB/m l EoNPV制剂与2 000 IU/mg B t制剂混用增效作用最明显,LC50为817.03μg/m l。对2龄茶尺蠖的杀虫速度,EoNPV+B t制剂(1.00×107PIB/m l EoN-PV+2 000 IU/mg B t)的LT50较单独使用EoNPV(2.00×107PIB/m l)缩短了2 d,且EoNPV+B t制剂对茶尺蠖具有拒食作用,茶尺蠖对EoNPV+B t制剂处理茶树的食叶量比单独使用EoNPV制剂的食叶量减少65.9%。EoNPV+B t制剂对茶刺蛾、茶银尺蠖等茶树鳞翅目害虫的兼治作用分别达85.8%和88.7%。多点田间药效试验结果表明,EoNPV+B t制剂药后10 d对茶尺蠖防效达81.80%~93.24%。更多还原

【Abstract】 Synergism of Bacillus thuringiensis（Bt） combined with Ectropis obliqua nucleopolyhedrovirus（EoNPV） against Ectropis obliqua was studied by bioassay in laboratory.The co-toxicity coefficient（CTC） of 2 000 IU/mg Bt mixed with five different concentrations of EoNPV were from 103.02 to 128.03,indicating the existing of the synergistic effects between EoNPV and Bt against E.oblique.Among the five combination treatment,1.0×10⁷ PIB/ml EoNPV with 2 000 IU/mg Bt（EoNPV+Bt） was the most synergistic one,with LC₅₀ of 817.03 μg/ml.Compared to the single treatment of EoNPV of（2.00×）10⁷ PIB/ml,EoNPV Bt treatment not only accelerated the killing speed to the 2nd instar of E.oblique larvae,lessening the median lethal time(LT₅₀) from 11.8 d to 9.8 d,but also carried the antifeeding activity,resulting in the feeding amount decrease by 65.9%.Field trials in three districts showed that the mortalities of E.oblique ranged from 81.80% to 93.24% after 10-day application of EoNPV Bt,whose dual effects made the mortality of Scopula subpunctaria up to 88.7%.更多还原