Control of cabbage Lepidoptera by naturally occurring arthropod predators
نویسندگان
چکیده
In recent years, pesticide resistance in some lepidopteran species, along with a general desire to reduce dependence on chemical pesticides, have led to increased interest in evaluating and enhancing the effects of naturally occurring biological control agents on the crucifer Lepidoptera. Due to the relative ease of documenting the impact of parasitoids on pest populations, however, virtually all the research on natural enemies have focused on parasitoids, while the role of predators has remained largely unexplored. Our work evaluating the effects of predatory arthropods on Pieris rapae in cabbage shows that generalist predators are responsible for much of the mortality of this pest in our area. We describe predator exclusion experiments and laboratory predation assays that demonstrate the important role of these natural enemies in reducing populations of P. rapae. As generalist feeders, these predators undoubtedly affect populations of other crucifer Lepidoptera as well and have the potential to survive in the crop at low pest densities by feeding on alternative prey. These attributes, along with their propensity to destroy the early stages of pests, make these predators potential key players in efforts to increase reliance on non chemical methods for managing crucifer Lepidoptera.
منابع مشابه
Experimental Evaluation of Arthropod Predation on Pieris rapae (Lepidoptera: Pieridae) Eggs and Larvae in Cabbage
Knowledge of factors causing mortality in herbivorous insects is essential to developing a better understanding of their population dynamics and more effective strategies to manage their abundance in crops. In this study we used 2 methods of predator exclusion to evaluate the effects of arthropod predators on Pieris rapae L. eggs and larvae on cabbages (Brassica oleracea variety capitata L.) in...
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