University of Guilan Caspian Journal of Environmental Sciences 1735-3033 24 2 2026 04 01 Alterations in the germination, spore production, vegetative growth and microbial enzymes of Beauveria bassiana and Metarhizium anisopliae isolates following treatments by some insecticides 465 474 7989 10.22124/cjes.2024.7989 EN Hossein Firouzbakht Department of Plant Protection, Faculty of Agricultural Sciences, University of Guilan, Rasht, Iran, 41637-1314 Arash Zibaee Department of Plant Protection, Faculty of Agricultural Sciences, University of Guilan, Rasht, Iran, 41637-1314 Mohammad Ghadamyari Department of Plant Protection, Faculty of Agricultural Sciences, University of Guilan, Rasht, Iran, 41637-1314 Journal Article 2024 09 03 Insecticides have influences on survival, growth and pathogenic pathways of entomopathogenic fungi (EF). Screening of EFs compatibility to insecticides is important to achieve an efficient pest control in integrated pest management. In the current investigation, potential effects of permethrin, fenitrothion, tebufenozide and trichlorfen were investigated on germination, mycelial growth, spore production and enzymatic activities of the native isolates of Beauveria bassiana (BBRR1, BBAL1, BBLN1, BBLN2) and Metarhizium anisopliae (MASA, MAAI). Spore production of the isolates significantly decreased following treatment with insecticides, mainly at the field dose concentration, except for permethrin and fenitrothion on BBAL1 and MASA. Germination rate significantly decreased after fungal isolates spores treatments with the insecticides except for MAAI. Treatment of the fungal isolates by insecticides reduced colony radial growth rate, especially after field dose treatments. Chitinase activity significantly decreased in the treated isolates, although no statistical differences were recorded on BBAL1 following treatment by fenitrothion, tebufenozide and trichlorfen. Finally, protease activity was also affected in the treated fungal isolates by insecticides. The current results showed that permethrin, fenitrothion, tebufenozide and trichlorfen negatively affected growth, development and spore production in addition to microbial enzymes involved in the pathogenic process. Some exceptions were observed mainly on BBAL1, which should be considered in the joint use of insecticides with the entomopathogenic fungi.     https://cjes.guilan.ac.ir/article_7989_3d8b99898b14e8f529363ffa486abf97.pdf