Effect of temperature on biological parameters of Oenopia conglobata contaminata (Menetries) by feeding on pomegranate green aphid, Aphis punicae Pass. under laboratory conditions

Characteristics such as lower developmental time, higher fertility and a large body size of natural enemies as biological control agents are important for their mass rearing. Oenopia conglobata contaminata (Col.: Coccinellidae) is one of the major predators of pests in the Orchards in Iran. The effect of five constant temperatures of 22.5, 25, 27.5, 30 and 32.5ºC on the development of the predator by feeding on pomegranate green aphid, Aphis punicae (Hem.: Aphididae) under laboratory conditions (55±5 RH and 16L: 8D h) was investigated. The developmental time of O. conglobata contaminata were 20.37, 18.31, 16.39, 14.34 and 11.74 days on above mentioned temperatures, respectively. The results showed that developmental time decreased with increasing temperatures. The lowest mortality was observed at 27.5oC and the lowest survival rate was recorded for eggs whereas survival of first instars larvae and pupae had the highest survival at above-mentioned temperatures. The results indicated that there were significant differences for developmental times in different temperature and moreover, 27.5 to 32.5oCwere optimum temperatures for the rearing of the lady beetle. The survival rate was determined to reduce at lower and higher temperatures than optimal. Lower temperature threshold and thermal constant for egg, total larval period, pupa and egg to adult by feeding on green pomegranate aphid were 8.32, 8.52, 9.34, 9.34oC and 59.17, 163.93, 56.17, 285.71 degree-day, respectively.