Cabbage Integrated Pest Management : An Ecological Guide.

Ecology of Insect Pests and Natural Enemies4ECOLOGY OF INSECT PESTS ANDNATURAL ENEMIESSUMMARYInsect ecology studies insects in their environment. The environment (e.g. climate,food sources, natural enemies) determines whether an insect population becomesa pest or not.Insects can damage plants by eating leaves, by sucking plant juices, or byfeeding inside the leaves. However, not all insect feeding reduces yield! Cabbageplants can compensate for feeding injury because more leaves and roots areproduced than actually needed for head formation. So, not all “pests” are “pests”!Actually, some insects are needed to keep the natural enemy population alive. Bysetting up insect zoos, the functions and life cycles of insects and natural enemiescan be studied.Natural enemies (predators, parasitoids, pathogens and nematodes) reduce pestinsect populations. They can be indigenous or reared and released into the field.The latter is becoming more and more important for many vegetable insect pests.A number of management and control practices for insect pests are described.Cabbage Ecological Guide - 200050