Study on survival rates of different stages of Exochomus nigromaculatus (Coleoptera: Coccinellidae) by using of mathematical curves

摘要

Study on survival rates of different stages of E. nigromaculatus by using of numerical curves were conducted. Experiments were done at laboratory conditions; 15, 20, 25, 30, 35, and 40°C, and 65±5% relative humidity, and 14:10 (L:D) photoperiod. Maximum survival rate was occurred at 30°C by 88.28% for immature stages from egg to adult, and minimum survival rate was occurred at 40°C by 8.88% for immature stages from egg to adult. Results were showed that all of adult coccinellids were alive until 64th day, and survival rate were 100% for this period. After 64th day, survival rates were decreased. At 120th day, last coccinellid was death. Biological equation of these adult coccinellid survival rates were: Y= -0.0003091x~2+ 0.00879x+ 0.9623 (For males); Y= -0.0001214x~2+ 0.00719x+ 0.9316 (For females).