The Biology and Seasonal Abundance of the Frit Fly, Oscinella frit,1 in Reed Canarygrass in Virginia

Abstract

Oscinella frit (L.) occurs throughout Virginia, but is more plentiful at higher altitudes. There are 3 generations each year in Virginia; the spring generation is the largest, the summer generation smallest. Frit fly populations closely parallel the seasonal changes in density of reed canarygrass and quantity of food per tiller. Males mate within 6 h following eclosion, females do not mate until the 2nd day. The mean in-copula time is 45 min. The average fecundity, egg viability and female longevity of the 3 generations were respectively: overwintering generation 16.6 eggs, 95.7%, 5.5 days; spring generation 59.0 eggs, 98.8%, 17.7 days; and summer generation 31.8 eggs, 41.9%, 26.4 days. In the laboratory frit fly adults preferred dead leaf sheaths attached to newly emerging tillers as oviposition sites.