Does Certain Host and Food Deprivation Period Affect Host Feeding and Oviposition Behaviour of Eretmocerus warrae (Hymenoptera: Aphelinidae)

Eretmocerus warrae (Naumann and Schimdt) is a thelytokous aphelinid parasitoid of the greenhouse whitefly, Trialeurodes vaporariorum (Westwood). It was first detected in New Zealand in 1997 during a survey of greenhouses in Auckland. We investigated the effects of certain duration of food and host deprivation after emergence on feeding, oviposition behavior and egg resorption of E. warrae with seven treatments (0, 5, 10, 15, 20 and 25 hours of food deprivation, and 24 hours of honey feeding) before being used for the experiment. The experiments were conducted at Institute of Natural Resources, Massey University, Palmerston North, New Zealand. Under 22±1°C, 60±5% RH and 16:8 h light:dark. Results indicated that the parasitoids deprived of food and hosts for 5 hours laid significantly more eggs, lived significantly longer and fed on and parasitised significantly more hosts (P<0.0001). With the increase in food and host deprivation period from 5 to 25 hours the average daily host feeding rate significantly increased (P<0.0001). Significant egg resorption was detected after 3 days of food and host deprivation (P<0.0001). However, in honey fed parasitoids, significant egg resorption occurred after 6 days of host deprivation (P<0.0001). This study suggests that food and host deprivation for 5 h is the optimal period for host feeding, fecundity and longevity in E. warrae.