Tiny Bug Could Bring Big Relief to Grain Producers

A tiny bug with a greedy appetite for other insects could help prevent damage to stored grain products.

Commonly called the larger pirate bug, Lyctocoris campestris is only about an eighth of an inch long and dark brown. It looks like a small stink bug or box elder bug. But its potential to control bad bugs in stored grain with fewer insecticides is as great as its appetite, according to Agricultural Research Serviceentomologist James Throne in Manhattan, Kan. ARS is the chief research agency of the U.S. Department of Agriculture.

Insects cause millions of dollars in damage to stored grain and other stored products annually in the United States. ARS researchers at the Grain Marketing and Production Research Center--in collaboration with Megha Parajulee at Texas A & M University and Tom Phillips at Oklahoma State University, formerly with ARS--developed and validated a computer model for simulating the growth of the larger pirate bug in grain bins. The model predicts how predator populations increase under different environmental conditions.

Young pirate bugs--naturally present in grain bins--are ready to feed on pests right after hatching. They live about 100 days when feeding on prey and can survive up to 20 days without food or water. That’s important for a predator if it has to wait between prey hatchings, according to Throne.

Pirate bugs eat larvae of Indianmeal moths, Mediterranean flour moths, almond moths, red flour beetles, saw-toothed grain beetles and warehouse beetles. Pirate bugs are the good guys compared to the pests they devour. They don’t get inside grain kernels, nor do they eat the grain--only other insects. Their presence in warehouses and storage facilities poses no threat to the quality of grain, and they are easily removed during processing.

New methods for controlling insect pests in stored grain products are being studied because insect pests are developing resistance to currently used insecticides and regulatory restrictions are limiting the use of others.

Scientific contact: James Throne, ARS Grain Marketing and Production Research Center, 1515 College Avenue, Manhattan, KS 66502, phone (785) 776-2796, fax (785) 776-2792, [email protected].