Pathogenicity of Beauveria bassiana and Metarhizium anisopliae on elm leaf beetle, Xanthogaleruca luteola Muller (Col., Chrysomelidae)
In current study, pathogenicity of two pathogenic fungi, Beauveria bassiana Vuellemin and Metarhizium anisopliae Sorokin were assessed on adults of elm leaf beetle, Xanthogaleruca luteola with four concentrations 105, 106, 107 and 108 spore/ml and control treatment using immersion and spraying methods. The experiments were conducted at controllable conditions, 25±1°C, 75±5% RH and photoperiod 12:12 h in growth chamber. Mortality rate in both methods in all treatments were recorded during 10 days. The values of LC50 and LC90 for B. bassiana were 2.7×106 and 7.72×106 spore/ml in immersion method and were 7.75×106 and 35.05×106 spore/ml in spraying method while these values for M. anisopliae were 2.68×106 and 7.99×106 spore/ml in immersion method and were 8.36×106 and 46.8×106 spore/ml in spraying method, respectively, it shown higher pathogenicity of B. bassiana in comparison with M. anisopliae. The lowest LT50 and LT90 for B. bassiana at concentration 108 spore/ml were 3.39 and 13.12 days while these values for M. anisopliae were 4.51 and 15.03 days respectively. The result shows that B. bassiana in both methods immersion and spraying causes more mortality during shorter time compare to M. anisopliae. According to findings of the current study, both fungi B. bassiana and M. anisopliae can be used in integration with other non-chemicals method for control of elm leaf beetle.