Occurrence of Entomopathogenic Fungi in Agricultural Soils from Isparta Province in Turkey and Their Pathogenicity to Galleria mellonella (L.) (Lepidoptera: Pyralidae) Larvae

Occurrence and pathogenicity of entomopathogenic fungi (EPF) from soils in six different sampling sites of six counties in Isparta, Turkey were investigated in 2013 to 2014. EPF were isolated from the soils using the Galleria bait method. During the study, 196 soil samples and 1080 Galleria mellonella (L.) larvae (Lepidoptera: Pyralidae) were used. Insect associated fungi were isolated from 777 (72%) out of 1080 larvae. The most abundant insect pathogenic fungi were Beauveria spp. (164 isolates) and Metarhizium spp. (40 isolates). Fusarium spp. was very abundant opportunistic fungi recovered comprising (45.69%) of the total isolates. The other opportunistic fungi, Aspergillus spp. (14.29%) and Penicillium spp. (2.83%), were less frequent. Pathogenicity of 55 fungal isolates belong to the genera Beauveria, Metarhizium, Fusarium, Aspergillus, and Paecilomyces lilacinus were evaluated versus 3rd and 4th instar larvae of G. mellonella. Isolates of Beauveria spp. and Metarhizium spp. proved to be the most virulent ones. Metarhizium isolate, BMAUM-M3003 was the most virulent isolate and had the shortest LT50 value (0.56 days). Beauveria isolates, BMAUM-E2001, BMAUM-E3001, BMAUM-E6001, BMAUM-K1001, and BMAUM-K4001 were also very effective against G. mellonella larvae (LT50= 1.43; 2.49; 2.56; 2.72; 2.84 days, respectively). Aspergillus spp. and Fusarium spp. isolates showed very low pathogenicity (0-10%). P. lilacinus had also very low infection with 30% mortality in 10 days. Beauveria and Metarhizium isolates proved to have potential to be used against a variety of agricultural pests.