Genetic improvement of beneficial insect…: Guthion-resistant parasite ready for implementation in walnuts

Because pesticides may depress populations of beneficial insects as well as target pests, biological control has historically played a limited role in integrated pest management (IPM). However, recent research has shown that pesticide-resistant parasites selected in the laboratory can be established in the field and enhance IPM programs. Continuing studies indicate that a Guthion-resistant strain selected at UCB performs well in two California orchards, and could be used to colonize other walnut orchards throughout the state. Additional releases would accelerate this process. Otherwise, large-scale establishment might take 5 to 10 years.

Pesticide-resistant beneficials — whether selected In the laboratory or genetically engineered — may someday play an expanded role in IPM programs and the reduction of pesticide use.