THE BIOLOGICAL CHARACTERISTICS OF INTERACTIONS BETWEEN “EPISYRPHUS BALTEATUS DE GEER” INSECTIVORE HOVERFLY ON CERATOVACUNA LANIGERA (ZEHNTNER) IN THO XUAN DISTRICT, THANH HOA PROVINCE

Tóm tắt

The growth process of Episyrphus balteatus passes 4 stages of development: egg, larva (maggot), pupa and adult. The average life cycle time of the fly at 27.8 0 C is 18.7 days, at 25.3 0 C is 20.1 days. The average life time of the fly at 27.8 0 C is 25.9 days, at 25.3 0 C is 28.6 days. The fly of E. balteatus lays eggs within 9 days of insemination with an average of 39.5  2.11 eggs/adult fly. On the sixth day, the maximum numbers of eggs are 5,6 eggs/adult/day. At mean temperature condition of 25.3 0 C, mean moisture of 82.5%, an 1instar maggot eats an average of 17.2 ± 0.37 aphids, a 2-instar maggot eats an average of 69.7 ± 0.62 aphids, a 3-instar maggot eats an average of 196.2 ± 2.15 aphids. At a temperature of 27.8 0 C, and moisture level of 77.6%, the maggot eats fewer aphids. An 1instar maggot eats an average of 15.9 ± 0.44 aphids, a 2-instar maggot eats an average of 57.5 ± 0.51 aphids, a 3-instar maggot eats an average of 188.7 ± 1.84 aphids.