Laboratory experiments were carried out to study some biological aspects of the seven spotted ladybird beetle, Coccinella septempunctata L. (Coleoptera: Coccinellidae) reared on four different artificial diets and two natural prey species (Aphis fabae and Rhopalosiphum padi) under laboratory conditions of 25±2 ̊C and 65±5 % R.H. Data indicated a positive correlation between food type (artificial or natural) and biological characteristics of the predator. A. fabae was the best prey for C. septempunctata, as the incubation periods of eggs was (4.58 days),the hatchability percentage (93.6%), eggs mortality (6.4%) and shortest total larval period (15.15 days) were recorded. The total larval mortality was the lowest (4%) when larvae were fed on 4th instar larvae of A. fabae. Feeding on natural preys, specially, on A. fabae, led to adults had longer longevity periods (57.06 days for females and 40.96 days for males) than those fed on the artificial diets. Also, females resulted from feeding on A. fabae deposited highest numbers of eggs (565.67eggs/ female). R. padi followed A. fabae as good diet for rearing C. septempunctata. Among the four artificial diets, diet (B; dried eggs yolk) was the best; as the incubation period of egg recorded (5.7 days), hatchability percentage (77.20%), mortality percentage of eggs (22.8%), total larval period (19.08 days), total larval mortality (24%) and longevity periods were (57.37 days for females and 33.81 days for males). Females resulted from feeding on diet (B) deposited (212.13eggs/ female). Diet (D) followed diet (B) giving promising results. The artificial diet (A) gave the least values of the characteristics of the predator C. septempunctata. |
