Life-History Parameters of Paracentrobia andoi (ISHII)(Hymenoptera, Trichogrammatidae), an Egg Parasitoid of the Green Rice Leafhopper, Nephotettix cincticeps UHLER (Homoptera, Deltocephalidae)

The effects of temperature on some of the life cycle parameters of Paracentrobia andoi were studied in a rearing experiment at constant temperatures, 20℃, 24℃, 28℃, and 32℃ under 16L-8D. The developmental period from egg to adult emergence shortened as the temperature was raised. The threshold temperature for development was about 13℃, and thermal constant was 202.06 day-degrees. Adults at 20℃ survived significantly longer than those at other temperatures, but there was no significant difference at 24℃, 28℃ and 32℃. The fecundity at 32℃ was significantly lower than that at other temperatures, but again, no significant differences were seen at 20℃, 24℃ and 28℃. Life cycle parameters also were calculated and compared. The intrinsic rate of increase (r_m) and capacity for increase (r_c) rose when the temperature was raised. These results are discussed from the standpoint of the parasitoid's capability as a natural enemy of N. cincticeps.