Abstract

Merzak Alloula Nahnah

Consumption rate and starvation tolerance of larvae and adult of Hippodamia variegata (Goeze) were studied on Aphis fabae Scopoli under laboratory conditions (25±1°C, 60±5% RH and 16h L: 8h D). The average daily feeding of different larval stage s: 1st, 2nd, 3rd, 4th instars and adults were 12±0.47, 22.1±1, 32±0.47, 48.7±1 and 58.2±0.55 aphids, re spectively. The average total feeding of larval stages 1st, 2nd, 3rd and 4th instars were 42.03±1. 65, 67.41±1.58, 105. 6±1.51 and 177.76± 1.65 aphids per day, respectively. The predation rate of 4th instar larva of H. variegata was the highest whereas the 1st instar larva consumed the lowest number of prey. Mean of feeding in male, virgin female and mated female per hour was 2.1±0. 1, 1.2±0.13 and 4.3±0.15 respectively. Average of starvation tolerance in larval instars 1st, 2nd, 3rd, 4th, male adult and female adult were 2.3, 2.95, 3.95, 5.35, 4.6 and 8.1 re spectively. A linear correlation curve showed the dependency of predation on the developmental stages of H. variegata. The results obtained here provide information about the consumption of H. variegata that might be useful for IPM programs.