黔南烟田斜纹夜蛾的生物防治效果

Biocontrol efficiency on Spodoptera litura(Fabricius) in Qiannan tobacco growing areas

为减少烤烟生产害虫防治过程中化学杀虫剂的使用量,有效防治烟田害虫,采用常规喷雾法,在烟田测定了7种生物杀虫剂(32 000 IU/mg苏云金杆菌可湿性粉剂,5%氟铃脲乳油,0.3%苦参碱水剂,20×10~9PIB/mL多角体病毒悬浮剂,240 g/L甲氧虫酰肼悬浮剂,0.6%印楝素乳油,60 g/L乙基多杀菌素悬浮剂)对斜纹夜蛾幼虫的防治效果。结果表明,0.3%苦参碱水剂3.0～4.0 g a.i/hm^2和240g/L甲氧虫酰肼悬浮剂120g a.i/hm^2的防治效果较好,施药后14 d对斜纹夜蛾幼虫的防效分别达到85.0%～92.6%和80.6%。因此,苦参碱和甲氧虫酰肼可作为防治烟田斜纹夜蛾的生物杀虫剂。

In order to reduce the use of chemical pesticides and effectively control pests in tobacco fields, the control efficiencies of seven biopesticides（32 000 IU/mg Bacillus thuringiensis wettable powder, hexaflumuron 5% EC, 0.3% matrine, 2 billion PIB/m L polyhedral virus suspension, 240 g/L methoxyfenozide suspension,0.6% azadirachtin emulsion concentrate and 60 g/L spinetoram suspension） on larvae of Spodoptera litura（Fabricius） in tobacco fields were investigated. The results showed that the control efficiencies of 0.3% matrine（applying at a rate of 3.0-4.0 g a.i/ha） and 240 g/L methoxyfenozide suspension（applying at a rate of 120 g a.i/ha） were higher than those of the other agents, which reached 85.0%-92.6% and 80.6%, respectively on the 14 th day after application. Therefore, matrine and methoxyfenozide can be used as biopesticides against Spodoptera litura（Fabricius）.