ABSTRACT
Since the recent emergence of the sweetpotato whitefly (SPW) Bemisia tabaci (Germ.) as a major pest of numerous crop species, there has grown a realization that alternative methods to SPW control were essential. Alternatives such as biological control by natural enemies of SPW are appealing because of their relatively economical and environmentally sound nature. However, the use of predators and parasites for control is presently hindered by our limited knowledge of these entomophagous agents (Gerling, 1990). The present study deals with predators as these organisms have had very notable success in several previous biological control efforts (Debach and Rosen, 1991). Despite the fact that there are several promising species of generalist predators that may be useful in suppression of SPW populations (Cohen and Byme, 1992) as well as some whitefly specialists (Hoelmer, et al., 1992 and Gerling, 1990), less attention has been paid to predators than to parasites as SPW control agents (Gerling, 1990). It is unfortunate that predators have received sparse attention in this matter because they offer a potential of very forceful control with their high prey destruction capabilities. It is the purpose of this paper to report results of studies that were aimed at evaluating several species of whitefly predators. This work was conceived as an effort to develop useful screening and evaluation tools for assessing candidate predators of SPW.
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