Effect of Temperature on Some Biological Parameters of Menochilus sexmaculatus (Fabricius) by Feeding on Pomegranate Green Aphid, Aphis punicae Pass

Characteristics such as lower developmental time, higher fertility and a large body size of natural enemies as biological control agents are important for mass rearing. Menochilus sexmaculatus (Fabricius) (Col.: Coccinellidae) is one of the major predators of pests in the orchards of Iran. The effect of six constant temperatures of 17.5, 20, 22.5, 25, 27.5 and 30 ºC were investigated on the development of the predator by feeding on the Pomegranate green aphid Aphis punicae (Hem.: Aphididae) under laboratory conditions (65 ± 5 RH and 16L: 8D h). The developmental time of M. sexmaculatus were 26.83± 0.61, 19.35 ± 0.23, 16.02 ±0.16, 11.66 ± 0.12, 10.45 ± 0.20 and 13.35 ± 0.33 days on above mentioned temperatures, respectively. The results showed that developmental time decreased with increasing temperature to 27.5 ºC. The lowest mortality was observed at 22.5ºC among the above-mentioned temperatures. The results indicated that there were significant differences for developmental times in different temperatures. Survival rate decreased away from the desirable temperature, 27.5 ºC, in both higher and lower orders. Lower temperature thresholds for eggs, larvae, pupae and adults were 10.69, 12.22, 12.83, 11.55ºC and thermal constants for egg, total larval period, pupa and egg to adult were 32.25, 83.33, 33.33, 166.66 degree-days, respectively, by feeding green pomegranate aphid. The results showed that optimum temperature were 25 to 27.5ºC for the rearing of the lady beetle.