Physiological and molecular characterization of Metarhizium isolates and their acaricidal activity against Tetranychus urticae Koch (Trombidiformes: Tetranychidae)

Abstract Background The two-spotted spider mite, Tetranychus urticae Koch (Trombidiformes: Tetranychidae), is one of the most damaging mites in agriculture. Due to concern for intensive use synthetic acaricides, entomopathogenic fungi represents a feasible alternative T. management. In present study, 7 isolates Metarhizium were characterized physiological and molecularly (based on ITS1-5.8s-ITS2 rDNA) evaluated their acaricidal activity [mortality, mean 90 lethal concentration (LC 50 : LC ) time (LT LT )] against under laboratory conditions. Results Sequencing rDNA region indicated that belong M. anisopliae . Ma114 (3.7 ± 0.006 mm day −1 ), Ma109 (3.5 0.009 Ma106 had highest radial growth rate (92.2 0.86%) Ma108 (94.4 1.07%) germination percentage. All pathogenic , causing mortality ranged from 45.3 85.3%. 1.2 2.8, 1.1 2.5, 2.8 × 10 8 conidia mL Ma110, Ma106, respectively, while 7.7 16.5, 7.2 16.1 days M110 Ma109, respectively. Conclusion Ma110 moderately virulent