| Abstract: | Similarities and differences in the biology, behavior and hemolymph proteins of the two closely related species, the bollworm, Heliothis zea (Boddie) and the tobacco budworm, Heliothis virescens (F.) were investigated. Both species had similar patterns of development when reared on wheat germ diet at 80°F in the laboratory. Both species needed a little over one month's time from egg laying to adult emergence. Larvae of both species had speedier development when reared at mean temperatures of 87° F on wheat germ diet or on cotton plant parts at 80° F. The threshold temperatures for bollworm and budworm development were calculated to be 55° F and 52.5° F, respectively. The food requirements of bollworm larvae were significantly greater than for budworm larvae in order to complete development. Mean weights for full grown larvae and pupae were 525 mg and 345 mg for bollworms as against 325 mg and 221 mg for budworms. Widths of head capsules cast off at various molts were measured and recorded. Larvae of both species were attracted to fruiting parts of cotton plants in field investigations and preferred them to foliage. The larvae of both species, however, developed and pupated successfully when only leaves were available for food. Existence of a cannibalistic trait was confirmed for both species.. |
|---|