Temperature, Photoperiod, and Aggregation Effects on Development, Diapause, Reproduction, and Survival in Corythucha cydoniae (Heteroptera: Tingidae)

Corythucha cydoniae (Fitch), the hawthorn lace bug, required an average of 55.6 – 18.5 days to complete development at temperatures ranging from 21 – 33°C. Nymphs emerged from eggs at 18°C but failed to develop further. Nymphal survival at 21°C was poor. Developmental thresholds for egg, nymphal, and total development were 13.3, 14.9, and 14.3°C, respectively. Thermal unit requirements for those stages were 162.9, 157.3, and 318.2 centigrade degree-days. Nymphal development was slightly accelerated by increasing the size of a cluster from one to three individuals at 24 but not at 27°C. Ovipositional rate was higher at 33 than 27°C, but total egg production was similar at both temperatures. Critical photoperiod for reproductive diapause was between 13:11 and 12:12 (L:D) at 24°C. Nymphal development was accelerated at short daylengths.