Effects of temperature on the growth and development in Aiolocaria hexaspilota (Coleoptera: Coccinellinae)

In order to explore the effects of temperature on the growth and development of Aiolocaria hexaspilota, the development duration in each development stage, development rate, development threshold temperature, effective accumulative temperature, survival rate, and larva body length were studied under the temperature of 15, 20, 25 and 28 ℃. Results showed that: within the temperature range of 15-28 ℃, all development duration shortened significantly, while the development rate speeded up with the rise of temperature. Using linear regression model to simulate the growth rate of each development stage of A. hexaspilota, the fitness was high and all the P value was less than 0.05, reached significant level. There was no significant difference in body length among 1-3 instar larvae under different temperatures. Whereas for 4th instar larva, the larva body length at 15 ℃ was obviously shorter than other temperature, only 11.48 mm. The results also showed that the survival rate of A. hexaspilota was influenced by temperature. With the increase of temperature, total survival rate trended down. At 28 ℃, survival rate reached the lowest value, only 54.53 %. In conclusion, the optimum temperature for A. hexaspilota growing was 15-20 ℃. The development threshold temperatures of A. hexaspilota from egg, 1-4 instar larvae to adults, and total duration were 9.84, 10.42, 11.67, 10.21, 9.91, 10.51 and 10.37 ℃, respectively. And the effective accumulated temperatures of above stages were 54.49, 26.77, 19.32, 27.35, 54.73, 73.37 and 269.77 ℃·day, respectively.