NUTRITION OF THE PALE WESTERN CUTWORM, AGROTIS ORTHOGONIA MORR. (LEPIDOPTERA: NOCTUIDAE): I. EFFECTS OF UNDERFEEDING AND ARTIFICIAL DIETS ON GROWTH AND DEVELOPMENT, AND A COMPARISON OF WHEAT SPROUTS OF THATCHER, TRITICUM AESTIVUM L., AND GOLDEN BALL, T. DURUM DESF., AS FOOD

Abstract

Larvae of the pale western cutworm fed ad libitum on Thatcher wheat sprouts required six instars to mature and increased in weight from 0.25 mg to near 700 mg in about 4 weeks. Larvae fed for only 2 hours each day required an additional instar, developed more slowly, and were smaller. The growth curves were generally similar as both exhibited a plateau before each molt, followed by a rapid rise. Of four artificial diets tested, only the two containing wheat-leaf juice permitted weight increases. The percentages of dry matter and nitrogen in the cutworm varied according to the stage of larval development and the variety of wheat sprouts fed. These factors, as well as underfeeding, also influenced the efficiency with which the cutworm converted its food to body tissue.