Scramble competition in Callosobruchus analis (Coleoptera : Bruchidae)

摘要

Larvae of Callosobruchus analis have been used. as model organisms of contest competition where only one adult can emerge from a bean irrespective of initial larval density. A new strain of C analis found recently exhibited a higher rate of two-adult emergence than a reference strain used in previous studies of larval competition. The higher rate of two-adult emergence of the new strain to exhibit such behavior was investigated in terms of resource requirement examining elytron length and change in larval weight. The results showed the new strain had, lower resource requirements than the reference strain. A lower encounter rate with opponents within a bean may prevent interference competition, as resource requirement becomes lower. We inferred, that the new strain was not a scramble competitor but a contest competitor with small resource requirements. We also attempted to estimate the results of larval competition between the two strains, which differ in their resource requirement.