Abstract

Background and Objective: Bemisia tabaci (B. tabaci) is the most widespread insect pest of broad range of greenhouse and field crops. It is a serious threat to crop production due to direct damage. The aim of this study was to study the virulence of three entomopathogenic fungi against Whitefly, Bemisia tabaci. Materials and Methods: This study was carried out during 2 successive seasons (2015 and 2016). In this study trading compounds of entomopathogenic fungi, Bio magic (Metarhizium anisopliae), Bio power (Beauveria bassiana) and Bio catch (Verticillium lecanii) were used. Three concentrations were used (1×107, 1×108 and 1×109 spores mL–1). Data were analyzed by one-way analysis of variance and followed by a least significant difference (LSD at 5%, p>0.05). Results: Under laboratory conditions V. lecanii, B. bassiana and M. anisopliae mortalities were happened after 3 days from treatment. The maximum percent of mortality (100%) was occurred after the 6th day from treatment with the 3rd concentration in all isolates. The 3rd concentration (1×109 spores mL–1) was the highly toxic in V. lecanii, B. bassiana and M. anisopliae to the adult of B. tabaci compared with the other two concentrations. Under field conditions the 3rd concentration (1×109) also was the best concentration against whitefly after the third application in V. lecanii, B. bassiana and M. anisopliae. The percent of reduction was ranged between 52 and 100% in all concentrations. V. lecanii was more virulence than B. bassiana and M. anisopliae against B. tabaci. Conclusion: These results confirmed that V. lecanii, B. bassiana and M. anisopliae isolates are promising agents for whitefly control in the field.