Conservation and evaluation of natural enemies in IPM systems for Bemisia tabaci

Abstract

Conservation biological control emphasizes the preservation and enhancement of natural enemies and is the cornerstone of all approaches to biological control. This review critically examines recent and current research efforts in conservation biological control by predators and parasitoids of Bemisia tabaci worldwide. A large number of natural enemy species have been identified from many agricultural systems. Further research has demonstrated that these natural enemies may act along with other mortality agents to inflict high levels of mortality on populations of B. tabaci. Less effort has been placed on determining the factors constraining or potentially enhancing biological control. The widespread use of broad-spectrum insecticides in many crops has severely hampered the contribution of predators and parasitoids to pest suppression. However, the arsenal of selective insecticides has grown in the past decade and their increased usage may permit the true integration of biological control into IPM systems. The effects of species interactions (e.g., intraguild predation) and host-plant attributes on disruption of biological control are poorly understood in most systems. Research in the area of habitat manipulation and enhancement is minimal. Very little research has addressed the evaluation of natural enemy effects on B. tabaci population dynamics in any system. As a result our ability to predict and exploit these effects for pest suppression are limited. Problems in estimating and interpreting parasitism are highlighted. Recent life table studies of B. tabaci in Arizona cotton are summarized to demonstrate how integration of natural enemies with use of selective insecticides resulted in the development of an efficient pest management system. Avenues for future research are discussed that may enhance the use of conservation biological control as a key tactic in IPM of B. tabaci. Published by Elsevier Science Ltd.

Voracity of Coccinella undecimpunctata: effects of insecticides when foraging in a prey/plant system

“…uptake of insecticide-contaminated food sources) (Hurej and Dutcher 1994;Longley and Stark 1996;Obrycki and Kring 1998;Youn et al 2003). Since it is known that the susceptibility of natural enemies to insecticides varies with the route of pesticide exposure (Longley and Jepson 1996a, b;Longley and Stark 1996;Banken and Stark 1998;Naranjo 2001;Grafton-Cardwell and Gu 2003), it is important to perform both topical and residual tests as they can provide valuable information about the expected and observed impacts of insecticides on natural enemies in the field (Tillman and Mulrooney 2000). On the other hand, in the field predator/ prey interactions generally occur in structurally complex patches (i.e.…”

Life-history parameters of Encarsia formosa, Eretmocerus eremicus and E. mundus, aphelinid parasitoids of Bemisia argentifolii (Hemiptera: Aleyrodidae)

“…According to Naranjo (2001) about 1500 papers on the biological control of Bemisia appeared between 1984 and the end of 2000. Between the end of 2000 and March 2003, we estimate that another 270 papers were published on natural enemies of whitefly.…”

Plano de amostragem do biótipo B de Bemisia tabaci na cultura do pepino

“…(Hemiptera: Aleyrodidae) é responsável por grandes perdas na produtividade do pepino e de diversas outras hortaliças no Brasil (Silva et al, 1992;Filgueira, 2000) e em outros países (Brown, et al, 1995;Ellsworth & Carrillo, 2001;Naranjo, 2001). Normalmente, os agricultores adotam o controle químico como única medida de controle desse inseto-praga.…”