Tobacco Budworm (Lepidoptera: Noctuidae): Temperature Effects on Mating, Oviposition, Egg Viability, and Moth Longevity

Abstract

Tobacco bud worm, Heliothis virescens (F.), pupae and moths were exposed to various temperatures in laboratory studies. Moths did not mate or oviposit at temperatures of 10°C and mating frequency was reduced at 37.8°C. Oviposition was higher at 21.1 and 26.7°C than at other temperatures tested. Also, the percentages of egg hatch were dramatically reduced at 32.2° and 37.8°C. Moth longevity decreased with increasing temperature. Mating, oviposition, and egg hatch were not affected when pupae were exposed to 10.0-18.3°C for 1-20 d. However, mating frequency was reduced in relation to lower temperature and duration of exposure. Conversely, mating percentages, oviposition, and egg hatch were reduced in relation to increasing temperatures (26.7-35°C) and duration of exposure. Outcrosses of male moths from pupae exposed to 15.6°C for 10 d resulted in reduced egg viability. Egg hatch was reduced as a result of out cross of male or female moths from pupae exposed to 35°C for as little as 3 d when paired with moths of the opposite sex from pupae held to emergence at 26.7°C.