Eggplant Integrated Pest Management AN ECOLOGICAL GUIDE

__________________________________________________________________Major Natural Enemies of Eggplant Insect Pests6.1 PredatorsPredators are animals that kill and eat other animals. They can be very large animals like lions that killand eat deers, cats that eat mice, or spiders that eat moths.Predators usually hunt or set traps to get their prey. They can kill or consume many preys and aregenerally larger than their prey. They are often generalists rather than specialists and can attackimmature and adult prey. When there is not enough prey around they may even eat each other!Predators of insect pests can be divided into groups such as beetles, true bugs, lacewings, predatoryflies, predatory mites and others like spiders and praying mantis.Predators are especially important natural enemies because they can often survive when there are noinsect pests around. They can switch to other food sources like crop visitors or neutrals, insects that livein the field but do not attack eggplants. They may even eat each other in times of low food availability ormove to the borders of the field to find prey. Predators are therefore often the first crop defenders againstpests. Predators follow the insect population by laying more eggs when there is more prey available.When no predators are around, pests that arrive in the field can easily increase their population.In this section, a number of predators that are important for eggplant pest insect control are described.6.1.1 Ladybeetles - CoccinellidaeAlso called ladybugs, ladybird beetles or coccinellid beetles. There are many different species ofladybeetles. However, not all ladybeetles are predators. Some, like Epilachna sp., are herbivores,particularly on solanaceous crops. Check feeding habits in insect zoo studies (section 4.6)!Primary prey: aphids, mites, whiteflies, small insects, insect eggs.Predatory stages: both adults and larvae.Description and life cycleAdult ladybeetles are small, round to oval in shape. The typical species present in many vegetables hasblack markings on red, orange or yellow forewings. Different species of ladybeetles have a different coloror different markings. Both larvae and adults of ladybeetles are predators: they eat aphids, smallcaterpillars, mites and insect eggs. Many ladybeetles prefer a diet of aphids but may switch to other preywhen there are not enough aphids. The larvae have a very different appearance from the adults. Theyare dark and look a bit like an alligator with 3 pairs of legs. There are usually 4 larval instars. Ladybeetlescan consume many prey on a day and can also travel around quite far (larvae may travel up to 12 m) insearch of prey.Life cycle of ladybeetle (from: Hoffmann et al, 1993)97Eggplant Ecological Guide