Effects of Food Plant and Diapause on Adult Survival and Fecundity of Colorado Potato Beetle (Coleoptera: Chrysomelidae)

Abstract

Currently, a mass rearing technique for the egg parasitoid, Edovum puttleri Grissell, of the Colorado potato beetle (CPB), Leptinotarsa decemlineata (Say), is lacking. An important component of such a system would be maximization of CPB egg production per day. The present studies characterized the effects of two factors, food plant and diapause history, on CPB egg production. Two greenhouse experiments determined the survivorship and fecundity of CPB on three food plants, potato, Solanum tuberosum tuberosum L. cv. Pungo; tomato, Lycopersicon lycopersicum (L.) Karsten var. lycopersicum, cv. Pick Red; and eggplant, S. melongena L. cv. Harris Special and cv. White. A third study compared the survivorship and fecundity of a field-collected population that had been in a state of diapause at 10°C for 6 mo with that of CPB from the same population cultured on potato in the greenhouse for the same period. Survivorship and longevity of adults did not differ among most food plants. Total egg mass and egg production per female and egg mass size were greatest on potato followed in decreasing order by tomato and ‘Harris Special’ eggplant in one study, and were greatest on tomato followed by potato, ‘White’ eggplant, and ‘Harris Special’ eggplant in the second study. Fecundity per day was greatest on potato and tomato in the first and second studies, respectively. Adult longevity, survivorship, total egg mass and egg production per female, and egg mass size did not differ between CPB that had diapaused and those that had not diapaused; however, fecundity per day was greater for CPB that had diapaused than for CPB that had not diapaused. The importance of these data in the development of a mass rearing technique for E. puttleri is discussed.