Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae) is one of the most important insect pests of potato (Solanum tuberosum L.). Because of the high value of potato crops, most growers approach management in a ...Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae) is one of the most important insect pests of potato (Solanum tuberosum L.). Because of the high value of potato crops, most growers approach management in a similar manner. Chemical control of arthropod pests in potato is the standard pest management practice, and will likely continue to be in the foreseeable future. This heavy reliance on chemical control has led to high levels of insecticide resistance. Strategies that rotate chemistries are critical in order to maintain insecticide efficacy, highlighting the immediate need to evaluate novel chemistries to continue to manage this pest successfully. Working with different populations of L. decemlineata, field and lab experiments were conducted to evaluate the baseline toxicity, ovicidal activity, and field efficacy of the novel insecticide tolfenpyrad to L. decemlineata. Lab assays revealed that tolfenpyrad was toxic to both larvae and adults, and that L. decemlineata treated egg masses had a 0% hatch rate. Potato field plots treated with tolfenpyrad had significantly fewer larvae, less defoliation, and higher tuber yields. These data will provide accurate field rates for proper labeling, a baseline reference for tracking changes in L. decemlineata susceptibility, as well as provide a novel chemistry to aid in resistance management programs.展开更多
Colorado potato beetle, Leptinotarsa decemlineata, is attracted to (S)-3,7-dimethyl-2-oxo-oct-6-ene-1,3-diol [(S)-CPB I], a male-produced aggregation pheromone. Pitfall trap studies were conducted to assess the relati...Colorado potato beetle, Leptinotarsa decemlineata, is attracted to (S)-3,7-dimethyl-2-oxo-oct-6-ene-1,3-diol [(S)-CPB I], a male-produced aggregation pheromone. Pitfall trap studies were conducted to assess the relative attraction of L. decemlineata adults to synthetic mixtures of the (S)- and (R)-enantiomers of the pheromone. Of the following blends that were tested: 97%(S):3%(R), 87%(S):13%(R), 73%(S):27%(R), and 50%(S):50%(R) (racemic blend), only the blend containing 97% of the (S)-enantionmer was attractive in one of the experiments. Our results demonstrate that the behavioral response of the beetle to pheromone-baited pitfall traps is unsubstantial in general, and that enantiomeric blends containing 13% or more of the opposite (R) enantiomer disrupt response to the pheromone. Any future research as well as integrated pest management strategies that incorporate CPB I as an aggregation pheromone should utilize blends containing more than 87% optical purity of the (S)-enantiomer of the pheromone.展开更多
文摘Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae) is one of the most important insect pests of potato (Solanum tuberosum L.). Because of the high value of potato crops, most growers approach management in a similar manner. Chemical control of arthropod pests in potato is the standard pest management practice, and will likely continue to be in the foreseeable future. This heavy reliance on chemical control has led to high levels of insecticide resistance. Strategies that rotate chemistries are critical in order to maintain insecticide efficacy, highlighting the immediate need to evaluate novel chemistries to continue to manage this pest successfully. Working with different populations of L. decemlineata, field and lab experiments were conducted to evaluate the baseline toxicity, ovicidal activity, and field efficacy of the novel insecticide tolfenpyrad to L. decemlineata. Lab assays revealed that tolfenpyrad was toxic to both larvae and adults, and that L. decemlineata treated egg masses had a 0% hatch rate. Potato field plots treated with tolfenpyrad had significantly fewer larvae, less defoliation, and higher tuber yields. These data will provide accurate field rates for proper labeling, a baseline reference for tracking changes in L. decemlineata susceptibility, as well as provide a novel chemistry to aid in resistance management programs.
文摘Colorado potato beetle, Leptinotarsa decemlineata, is attracted to (S)-3,7-dimethyl-2-oxo-oct-6-ene-1,3-diol [(S)-CPB I], a male-produced aggregation pheromone. Pitfall trap studies were conducted to assess the relative attraction of L. decemlineata adults to synthetic mixtures of the (S)- and (R)-enantiomers of the pheromone. Of the following blends that were tested: 97%(S):3%(R), 87%(S):13%(R), 73%(S):27%(R), and 50%(S):50%(R) (racemic blend), only the blend containing 97% of the (S)-enantionmer was attractive in one of the experiments. Our results demonstrate that the behavioral response of the beetle to pheromone-baited pitfall traps is unsubstantial in general, and that enantiomeric blends containing 13% or more of the opposite (R) enantiomer disrupt response to the pheromone. Any future research as well as integrated pest management strategies that incorporate CPB I as an aggregation pheromone should utilize blends containing more than 87% optical purity of the (S)-enantiomer of the pheromone.