(Acanthoscelides obtectus), a beetle of the family Bruchidae that infests leguminous crops. The body is oval and measures 2–5 mm in length. The coloration is copper brown, except on the abdomen and the tips of the elytra, which are yellowish red.
Bean weevils appear when the bean plants finish blooming and the pods begin to ripen. They reproduce in the field and in storehouses at a temperature of 13°–31° C. The female deposits the eggs (an average of 45) in clusters in the cracks of dried pods or on or between the seeds. Within four days the larvae move about freely and penetrate the seeds, where they develop, pupate, and become beetles. The developmental cycle of the bean weevil takes 34–60 days, depending on the temperature. Under normal conditions it dies after producing three or four generations.
The bean weevil is found in Western Europe and the USSR, primarily in Transcaucasia, Krasnodar Krai, and the Ukrainian SSR. It infests beans and, to a lesser extent, chick-peas, vetchlings, peas, lentils, broad beans, and soybeans. The damaged seeds are inferior in nutritional value and sowing quality.
Control measures include the sowing of uninfected seeds, the chemical treatment of the plants when the pods are ripening, postharvest plowing, disinfection of storehouses, fumigation of food and seed beans with pesticides, and the refrigeration and freezing of infested beans or the heating of seeds to a temperature of 18° C for 20 minutes.