Morphological and molecular identification of entomopathogenic fungi isolated from different regions of Antalya, determination of their efficacy against Aphis gossypii and Myzus persicae

In this study, the effectiveness of entomopathogenic fungal species isolated from different counties of Antalya province against Aphis gossypii and Myzus persicae was investigated. For this purpose, between 2018-2020, entomopathogenic fungi were isolated from 205 soil samples and 203 aphid individuals exposed to fungal infections taken from Aksu, Alanya, Demre, Döşemealtı, Finike, Gazipaşa, Kaş, Kemer, Kepez, Konyaaltı, Korkuteli, Kumluca, Manavgat, Muratpaşa and Serik counties of Antalya province, where agricultural activities were carried out intensively, and they were identified using molecular methods. According to the results obtained, in the isolations made from soil samples, thirteen different fungal species belonging to seven genera 23 of them were Beauveria bassiana, 6 Cunninghamella elegans, 2 Cu. echinulata, 5 Clonostachys rosea, 1 Cl. rogersoniana, 3 Isaria farinosa, 2 Fusarium proliferatum, 3 F. fujikuroi, 2 F. acacia mearnsii, 1 F. oxysporum, 3 Penicillium bilaiae, 1 Trichoderma atroviride and 1 T. harzianum were isolated. In the isolations made from infected aphids, five different fungal species belonging to four genera 12 of them were B. bassiana, 2 Purpureocillium lilacinum, 2 Aspergillus insuetus, 2 A. flavus and 1 Alternaria alternata were isolated. ITS1 / ITS4 PCR products of all fungal isolates belonging to the ITS region, 983/2218 PCR products belonging to mRNA translation elongation factor 1-alpha (EF1 alpha) gene region of BbSr-2, BbDs-4, BbDm-2, BbFn-2, BbKm-2, PlKa-1, PlMp-1 isolates and PCR products obtained from A. gossypii and M. persicae using primers COIdegF1 / COIdegR1 that sequences have been determined. Sequence data of isolates were compared with similar species in GenBank with the help of NCBI BLAST analysis. According to the result of BLAST analysis, each species showed 99-100% similarity with other species in GenBank, and thus, the molecular identifications of fungal isolates and A. gossypii and M. persicae were confirmed. Phylogenetic dendograms were obtained by using the sequence sequences of the isolates. The obtained entomopathogenic fungal isolates were tested against adult A. gossypii and M. persicae at a concentration of 1 × 107 conidia mL− 1. In preliminary pathogenicity tests, five B. bassiana isolates with high virulence (BbFn-2, BbKm-2, BbSr-2, BbDs-4 and BbDm-2) were tested at 5 different spore concentrations (1x105, 1x106, 1x107, 1x108 and 1x109 spores mL-1) against nymphs and adults of A. gossypii and M. persicae in petri dishes and pot trials. At these tested doses, the isolates BbSr-2, BbKm-2 and BbDm-2 in petri dish and pot experiments caused 83.3%, 93.3%, 93.3%, 100% and 100%; 96.7%, 96.7%, 96.7%, 100% and 100%; 80%, 93.3%, 96.7%, 100% and 100% mortalities, respectively, in adult A. gossypii; 100%, 100%, 100%, 100% and 100%; 86.7%, 93.3%, 96.7%, 100% and 100%; 90%, 93.3%, 93.3%, 100% and 100% mortalities, respectively, in adult M. persicae on the 10th day of application. While the LT50 and LT95 values of the isolates BbSr-2, BbKm-2 and BbDm-2 were 4.66, 6.82 and 5.26 days, respectively, for adult A. gossypii, they were determined as 4.90, 4.66 and 3.95 days, respectively, for adult M. persicae. As a result, BbSr-2, BbKm-2 and BbDm-2 isolates of B. bassiana, which showed similar pathogenicity values, were determined as the most virulent isolates against A. gossypii and M. persicae.