Females of Bruchidius atrolineatus (Pic) lay their eggs in the fields on maturing or dry pods of their host plant, Vigna unguiculata. Under experimental conditions in the presence of maturing and dry pods connected with the plant, 80% of eggs are laid on maturing pods. The preference for maturing pods is observed in two generations of B. atrolineatus and varies with the age of females. In the presence of pods separated from the plant, 69% of eggs are laid on dry pods. These results show the importance of methodology during insect behavioural studies. In the absence of choice, reproduction of B. atrolineatus females is more stimulated with dry pods than with maturing ones. These experiments show that factors which influence the choice of the pods are probably different from those stimulating oviposition.
