COPULATION AND ITS DURATION AFFECTS FEMALE WEIGHT, OVIPOSITION, HATCHING PATTERNS, AND OVARIAN DEVELOPMENT IN THE WESTERN CORN-ROOTWORM (COLEOPTERA, CHRYSOMELIDAE)

To understand the relationship between copulation and ovarian developm ent in the western corn rootworm, Diabrotica virgifera virgifera LeCon te, newly emerged virgin beetles were used to establish female groups of various copulatory durations. The results demonstrate that a mating of greater-than-or-equal-to 1 h stimulates an increase in weight, egg -laying, and ovarian development. This stimulation in females mated fo r 1 h (none contained sperm in the spermatheca at the time of dissecti on) was transitory and lasted 1-2 wk. Females that mated for 2 h (cont ained sperm in the spermatheca at the time of dissection) were indisti nguishable in weight, egg-laying, and ovarian development from females mated until natural completion; they were stimulated to a sustained m ature ovarian state and were capable of laying eggs for at least 4-5 w k after mating. Unmated females of similar ages underwent limited ovar ian development and rarely laid eggs.