Three criteria, development, flight, and oviposition, were used to compare a laboratory-adapted and wild-type colony of Trichoolusia ni. The laboratory-adapted colony was further examined to determine the effect of larval crowding and starvation on the above criteria. The laboratory-adapted colony displayed a shorter development time and higher immature mortality than the wild-type colony. Differences in flight activity between and within the colonies were observed. Wild-type mated females were the most active group of tested moths. The oviposition rate of the laboratory-adapted colony was higher than the wild-type colony. Innate differences in parent populations and selective pressures during the rearing of the laboratory-adapted colony may explain differences between the colonies. Larval crowding resulted in prolonged development time, lower pupal weight, increased larval mortality, and increased adult longevity. Starvation during the larval stage produced similar changes. Flight activity declined with the degree of larval crowding and starvation. Larval crowding and starvation also resulted in a decline in adult fecundity and mating frequency. It is postulated that stress to the larvae resulted in a decline in energy sources to be used in the adult stage, producing docile adults. / M.S.

The roles of ocelli and octopamine in regulating the onset, intensity, and duration of cabbage looper moth flight activity were examined. This was achieved by studying the flight activity of control, sham, and anocellate moths with and without octopamine treatment. Sham and anocellate moths were produced by cauterization in last-instar larvae, of ocellar primordial cells for anocellate moths, and of non-involved cells for sham moths. Flight activity of moths was monitored by a computerized actograph under normal light (LD) conditions, under advanced-sunset, and under constant dark (DD) conditions to determine the effect of ocelli on flight activity. The role of octopamine was investigated by treating the three groups of moths topically with octopamine dissolved in dimethyl sulfoxide (DMSO) and with DMSO alone, and comparing flight activity before and after treatment. Results support a combined role for ocelli and the compound eyes in determining flight initiation times, and a role for ocelli in determining flight intensity. These roles were more pronounced in males than in females. It was found that the cauterization operation itself decreases flight activity in sham moths. No evidence was found that supports the existence of an octopamine effect on flight activity in any of the groups of moths when octopamine is topically applied. / Master of Science