Evaluation of entomopathogenic fungi against Tetranychus urticae (Acari:Tetranychidae)

The effectiveness of entomopathogenic fungi Metarhizium anisopliae (4556 and V275), Metarhizium flavoviride, Lecanicillium lecanii and Beauveria bassiana on different development stages of Tetranychus urticae were investigated in petri dish and pot experiments. All studies were conducted at 25±1oC temperature, 70±5% relative humidity and a light cycle of 16h in a climate room. The density of inoculum was the same for all fungi and adjusted to 1x107 conidia/ml. The result of the experiments showed that the virulance rate of entomopathogenic fungi on T. urticae eggs varied between 11.8%-14.3% in petri dish experiment and 12.8%-17.0% in pot experiment. Entomopathogenic fungi showed 57.3-90.3% and 29.5-67.5% mortality rates for mobile stages of T. urticae in Petri dish and pot experiments, respectively. T. urticae adults were more susceptible to fungal infection than egg, larva and nymphal stages. All fungi showed the lowest mortality on T. urticae eggs. All tested entomopathogenic fungi in petri dish experiments were more effective than the pot experiments. As a result, entomopathogenic fungi could be used as potential control agents to T. urticae.