effects of different temperatures and relative humidity on the development, mortality and nymphal predation of Anthocoris minki

Mass rearing techniques are a necessity in developing a suitable and economic biological control method. Anthocoris minki Dohrn (Heteroptera: Anthocoridae), which is successfully reared for use in biological control, is a promising indigenous Anthocoris species for biological control of Agonoscena pistaciae Burckhardt and Lauterer (Homoptera: Psyllidae) in pistachio orchards. Development time of nymphal instars, mortality percentage and prey consumption of A. minki fed on Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) eggs were studied at three constant temperatures (20, 25 and 30 ± 1°C) and two relative humidity levels (40 and 65 ± 5%) under laboratory conditions. Temperature and r.h. significantly affected development time and nymphal prey consumption of A. minki . Duration of incubation and total nymphal development time decreased significantly with each increase in temperature. Total nymphal development time of A. minki at 40% and 65% r.h. was 18.6 and 18.6 days at 20°C; 13.7 and 14.6 days at 25°C; and 10.8 and 11.8 days at 30°C, respectively. The shortest nymphal development time and highest nymphal mortality percentage were recorded at 30°C and 40% r.h. The lowest nymphal mortality was 30.1% and 32.1% at 40% and 65% r.h., respectively, at 25°C; the highest nymphal mortality was 51.5% and 52.1% at 20° and 30°C, respectively, and 40% r.h. The highest average number of E. kuehniella eggs consumed was 123.1 at 20°C and 65% r.h., and the lowest was 86.4 at 30°C and 40% r.h. during nymphal development time of A. minki .