Morpho-molecular characterization of two Syrian soil-sourced isolates of Beauveria (Bals.) Vuill.

Abstract Background The genus Beauveria (Bals.) Vuill. includes many species, some of which are limited to specific regions while others are distributed worldwide. The diversity of Beauveria species is poorly investigated in Syria and most studies lack proper diagnosis of species. Entomopathogenic isolates of this genus were obtained using the Galleria Bait Method. This study aimed to identify these isolates based on morphological characterizations combined with molecular data, using nuclear ribosomal internal transcribed spacer (ITS) and elongation factor 1-alpha (EF1-α) sequences. The diversity of this genus in Syria has also been evaluated using a phylogenetic analysis of available ITS sequences of Syrian isolates in the GenBank. Results Two entomopathogenic isolates, B195 and B243, were detected in the soil of agro-ecosystems in the Syrian coastal region. Morphological and molecular information revealed that these two isolates belong to Beauveria bassiana (Bals.) Vuill. (Hypocreales: Cordycipitaceae) with 514 bp and 284 bp for the sequences of each isolate for ITS and EF1-α, respectively. Pathogenicity test showed 100% mortality of Galleria mellonella L. larvae 2–3 days post-fungal exposure for both isolates. The phylogenetic tree showed that all Syrian sequences of Beauveria clustered within the species B. bassiana, with a considerable intraspecific diversity, except for two isolates previously identified as B. bassiana, which are closely related to Beuveria pseudobassiana S.A. Rehner and Humber. Conclusions This study presents a morpho-molecular characterization of two Syrian soil-sourced B. bassiana isolates highly pathogenic to G. mellonella larvae and clarifies their phylogenetic placement. Depending on our findings, further exploration studies of the genus Beauveria in Syria are still needed to better our understanding of the diversity and distribution of this entomopathogen in Syria.