Influence of Different Legume Seeds on the Development, Oviposition, and Digestive Enzyme Activity of Callosobruchus chinensis L. (Coleoptera: Chrysomelidae)

In this study, the effects of five bean seeds (Vigna radiata, Pisum sativum, Vigna unguiculata, Vicia faba, and Glycine max) on the development, survival, oviposition, and digestive enzyme activities of C. chinensis were investigated. The duration of C. chinensis development from egg to adult was shortest when reared on V. radiata (26.97 d) and longest on G. max (30.92 d) (p < 0.01). Similarly, the emergence rate of C. chinensis was highest on V. radiata (66.11%) and lowest on G. max (33.89%) (p < 0.01). Significant differences in the fecundity of C. chinensis were also detected, with the highest values on V. radiata (63.36 eggs/female), followed by P. sativum (54.27 eggs/female), V. unguiculata (51.30 eggs/female), V. faba (42.47 eggs/female), and G. max (37.29 eggs/female) (p < 0.01). For an equal initial insect number, after continuous rearing for 30, 60, or 90 d, there were significantly more offspring on V. radiata than on the other species, with the fewest offspring detected on G. max (p < 0.01). Although CL activity (p = 0.33) in C. chinensis did not differ significantly among the different legume species, activities of PEP (p < 0.01) and α-AMS (p < 0.01) in C. chinensis were all highest on V. radiata and lowest on G. max, and activities of LPS (p < 0.01) were highest on G. max and lowest on V. radiata. The differences in population dynamics associated with different bean seeds may be related to the activity of particular digestive enzymes, which play important roles in insect nutrient metabolism and growth. Our results indicated that V. radiata is the most suitable host diet, whereas G. max is the least suitable for the development of C. chinensis.