Effect of temperature on some biological characteristics of Oenopia conglobata contaminata (Menteries) in feeding on the green peach aphid, Myzus persicae (Sulzer) in laboratory conditions

Characteristics such as rapid growth, longer longevity, shorter developmental time, higher fertility and larger body size are important criteria for selecting and initializing mass rearing of natural enemies. Oenopia conglobata contaminata (Menteries) (Col: Coccinellidae) is one of the major predators of insect pests in the orchards of Iran. The effect of five constant temperatures of 22.5, 25, 27.5, 30 and 32.5±? °C were investigated on the developmental rate of the predator by feeding on the green peach aphid, Myzus persicae (Sulzer) (Hem.: Aphididae), under laboratory conditions (55 ± 5% RH and  16L: 8D h). The results showed that there were significant differences between the five temperatures in terms of developmental time. Total developmental times at above-mentioned temperatures were 24.02±0.4, 19.68±0.7, 17.15±0.33, 14.09±0.39 and 14.32±0.25 days respectively. Minimum survival rate was recorded for the first larval instar and maximum was for the third and fourth larval instars and pupa. The highest mortality rate was observed at 22,5 and 32,5 °C. The lower temperature threshold and thermal constant for entire developmental time were estimated by using the simple linear regression model. The lower developmental thresholds of egg, larva, pupa and total immature stages were 9,99, 10,58, 9.63 and 8,48 °C  respectively and the thermal constant required at the above mentioned periods were 43,1, 163,93, 71,9 and 322,58 DD respectively. The results showed that 25 to 30 °C are suitable temperatures for rearing this predator.