Presently, chemical control is the main tool used to control the E. It is estimated that egg parasitoids reduce E. However, intensive use of insecticides has caused severe damage to parasitoid populations ( Radjabi 1995). The scelionid egg parasitoid Trissolcus grandis Thompson (Hymenoptera: Scelionidae) had a very important role in reducing Eurygaster integriceps (Puton) population ( Radjabi 1995 Critchley 1998). The main objective of this book chapter studying the insecticide side effects on development, parasitism or predation efficacy and emergence capacity as well as to preserve effective biological control agents is a combination of tactics including an understanding of the biology and behaviour of arthropods (parasitoids, predators and spiders), detailed monitoring of life history and population dynamics of pests and natural enemies, employment of selective pesticides, application only when absolutely necessary, basing chemical control on established economic injury levels and application at the least injurious time. There is great potential for increasing the benefits derived from naturally occurring biological controls, through the elimination or reduction in the use of pesticides toxic to natural enemies. The importance of such agents often becomes quite apparent when pesticides applied to control one pest cause an outbreak of other pests because of the chemical destruction of important natural enemies. The existence of naturally occurring biological control agents is one reason that many plant-feeding insects do not ordinarily become economic pests. Most biological control agents, including predators, parasitoids and spiders, at work in the agricultural and urban environments are naturally occurring ones, which provide excellent regulation of many pests with little or no assistance from humans. 1968) and cause high mortality to nectarfeeding parasitoids for as long as some weeks after insecticide application ( Stapel et al. ![]() However, systemic insecticides can potentially contaminate floral and extrafloral nectar when systemically distributed throughout the plant ( Lord et al. In contrast with nonsystemic insecticides, many systemic insecticides and their metabolites are claimed to be fairly safe for beneficial insects because direct exposure to these chemicals occurs when insects feed on plant tissue. 1996 El-Wakeil & Vidal 2005 El-Wakeil et al. The integration of chemical and biological control is often critical to the success of an integrated pest management (IPM) program for arthropod pests ( Smilanick et al. In fact, they are a prerequisite of Integrated Pest Management. But to achieve a satisfactory control of complexes of pests, selective pesticides are also indispensable. ![]() Every crop is infested by various pests some but not all of them may be controlled by biological means using pathogens, predators, parasitoids and spiders. ![]() Therefore, studying the side effect of insecticides on the natural enemies is highly required to exclude the detrimental effects on the natural enemies. Recently, plant protection strategy has recommended, minimizing the use of chemical pesticides.
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