Effect of food supply on reproductive potential of Eretmocerus warrae (Hymenoptera: Aphelinidae)

Abstract

Eretmocerus warrae (Naumann & Schmit) is a thelytokous parasitoid of greenhouse whitefly, Trialeurodes vaporariorum (Westwood). It was first detected in New Zealand in 1997 during a survey of greenhouses in Auckland. Under 22±1°C, 60±5% RH and 16:8 h light:dark, the effect of food supply on longevity, host feeding, fecundity and parasitism in E. warrae was investigated with four treatments: (1) no food and no host, (2) 10% honey solution and no host, (3) 40 2nd instar nymphs per day and no honey, and (4) 40 2nd instar nymphs per day and 10% honey solution. Results showed that parasitoids lived significantly longer when given honey but no host (8.8 days) than parasitoids given the other treatments (2.5-5.5 days) (P<0.0001). Honey supply significantly reduced host feeding (P<0.05). There was no significant difference (P>0.05) in lifetime fecundity (32.4-34.7 eggs), parasitism rate (14.7-16.0%) and superparasitism rate (10.3-11.4%) between parasitoids given hosts with or without access to honey.