Bionomics of the Bean Seed Maggot, Delia florilega (Diptera: Anthomyiidae), Under Controlled Conditions

Abstract

Seeds of peas and legumes attracted more ovipositing females of the bean seed maggot (BSM), Delia florilega (Zetterstedt), than seeds of cucurbits and corn. A bacterium, Pseudomonas sp., and a yeast, Cryptococcus laurentii var. laurentii , isolated from squash seeds and cultured on squash-seed-exudate agar, stimulated BSM oviposition. More eggs were laid between 1200 and 1800 hours, but some oviposition occurred at all hours. Mean fecundity was higher at 20°C (192.6 eggs per female) than at 25 or 30°C, but the percentage of fertile eggs was highest at 25°C. At 20°C, mean longevity was 58.9 and 46.4 d for females and males, respectively. Eggs hatched at all temperatures tested (5–40°C). At 25°C, 90.0% of the eggs hatched and 81.0% of these larvae pupated; however, at 5 and 40°C, only 8.6 and 50.0% hatched, respectively, and resulting larvae did not complete development at these temperatures. Larvae reared at 10 and 15°C entered pupal diapause. At constant temperatures, averages of 31.6, 219.9, and 236.8 degree-days were required for egg, larval, and pupal development above threshold temperatures of 6.4, 5.6, and 4.6°C, respectively, and 486.5 degree-days were required for development from egg to adult above an average threshold of 5.2°C.