The effects of different temperatures and relative humidity on the nymphal development, mortality and prey consumption of Anthocoris nemoralis (F.) (Heteroptera: Anthocoridae)

Anthocoris nemoralis (F.) (Heteroptera: Anthocoridae) is one of the most effective natural enemies of Cacopsylla pyri (L.) (Homoptera: Psyllidae) which is an important pest of pear trees. Development time of nymphal instars, mortality percentage and prey consumption of A. nemoralis feeding on Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) eggs were studied at two constant temperatures (20 and 25±1°C) and two relative humidity levels (30 and 60±5%) under laboratory conditions. Temperature and relative humidity significantly affected nymphal development time of A. nemoralis. Duration of total nymphal development time significantly decreased with increase in temperature. Total nymphal development time of A. nemoralis at 30 and 60% relative humidity was 19.17 and 16.47 days at 20°C; 13.75 and 13.00 days at 25°C, respectively. The highest nymphal mortality was 67% at 20°C and 30% relative humidity. The average number of E. kuehniella eggs consumed at 30 and 60% relative humidity was 124.42 and 139.74 at 20°C; 154.00 and 123.22 at 25°C, respectively, during nymphal development time of A. nemoralis.