Journal of Applied Entomology (2007) 131, 333-337
A.F. Janmaat, J. Ware and J. Myers (2007)
Effects of crop type on Bacillus thuringiensis toxicity and residual activity against Trichoplusia ni in greenhouses
Journal of Applied Entomology 131 (5), 333-337
Abstract: We assessed the efficacy and persistence of a Bacillus thuringiensis kurstaki (Btk) formulation (Dipel) against Trichoplusia ni (Hübner) (Lep., Noctuidae), the cabbage looper, on three greenhouse vegetable crops (tomato, bell pepper and cucumber). First, T. ni larvae were fed leaf discs treated with Btk to assess how Btk toxicity varies with host plant. Secondly, T. ni larvae were fed leaf discs harvested from plants that had been sprayed with Btk 1, 5 and 9 days previously to assess the residual activity of Btk toxicity in greenhouse environments. Mortality of T. ni larvae fed tomato leaf discs was significantly higher than T. ni fed cucumber or pepper leaf discs. The toxicity of Btk had declined by less than 50% after 9 days, which suggests that Btk persistence is lengthy in greenhouse environments. No crop effects on the residual activity of Btk were found. These results demonstrate that the greenhouse environment and the crop should be considered when using Btk for insect management on greenhouse crops.
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Link to article at publishers website
Database assignments for author(s): Alida F. Janmaat
Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
environment/habitat manipulation
