Biological control of whiteflies

Abstract

Whiteflies are major insect pests worldwide of many greenhousegrown horticultural crops, including ornamentals and vegetables, causing both direct feeding damage and vectoring certain diseases. Therefore, the primary way of suppressing whitefly populations, in general, on vegetable and ornamental crops, is the use of insecticides although over reliance on insecticides has resulted in the development of resistant whitefly populations. The use of biological control, which includes the augmentative introduction of parasitoids, predators, and applying entomopathogenic fungi, has been an important strategy in regulating whitefly populations in greenhouse production systems. However, biological control agents by themselves may not be entirely successful in sufficiently regulating whitefly populations, especially on ornamental crops. Furthermore, plants themselves may inhibit the effectiveness of biological control agents, which reduces regulation of whitefly populations. As such, there is interest, by greenhouse producers, in using insecticides in conjunction with biological control agents as a means to effectively suppress whitefly populations. Therefore, this chapter will address three main points: 1) provide an overview regarding the use of biological control in regulating whitefly populations in greenhouse production systems using parasitoids, predators, and entomopathogenic fungi including benefits and limitations; 2) assess the influence of plants on biological control agents and how this impacts their ability to regulate whitefly populations; and 3) determine if it is feasible to use insecticides in combination with biological control agents to suppress whitefly populations in greenhouse production systems.