The two-spotted spider mite, Tetranychus urticae, is a major pest of crops worldwide. In this study the effectiveness of ethanolic extracts from wild oregano (Lippia origanoides) and bushy lippia (Lippia alba) and that of entomopathogenic fungi (Paecilomyces fumosoroseus, Beauveria bassiana and Cladosporium sp.) to control Tetranychus urticae was evaluated. Ethanolic extracts were evaluated at different concentrations (2.5, 5.0, 7.5 and 10%) using the leaf disk immersion technique. Also, the effect of conidial suspensions of the fungi on mortality and oviposition of T. urticae was evaluated. The presence of alkaloids, flavonoids, phenols and tannins, essential oils and saponins was verified in the plant material used in our study. Ethanolic extracts when used at a concentration of 10% showed acaricidal effects on T. urticae, as evidenced by the mortality rates (83.3 and 78.3% caused by oregano and bushy lippia, respectively). Similarly, a higher mortality rate was observed when the mites were treated with Cladosporium sp., which is 72% higher than the control, while P. fumosoroseus and B. bassiana showed similar mortality rates at around 45.5 and 54.5% higher than the control. Our results showed that ethanolic extracts and acaropathogen fungi are promising agents for the management of T. urticae, although their field efficacy remains to be evaluated.
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