Characterization of Two Species Complex Isolates from the Ambrosia Beetle .

Ambrosia beetles are insect vectors of important plant diseases and have been considered as a threat to forest ecosystems, agriculture, and the timber industry. Several factors have been suggested as promoters of the pathogenic behavior of ambrosia beetles; one of them is the nature of the fungal mutualist and its ability to establish an infectious process. In Mexico, is an invasive ambrosia beetle that damages many agroecosystems. Herein, two different isolates from the ambrosia beetle belonging to the genus are reported. Both isolates belong to the species complex (FSSC) but not to the Ambrosia clade (AFC). The two closely related isolates are pathogenic to different forest and agronomic species, and the morphological differences between them and the extracellular protease profile suggest intraspecific variability. This study shows the importance of considering these beetles as vectors of different species of fungal plant pathogens, with some of them even being phylogenetically closely related and having different pathogenic abilities, highlighting the relevance of the fungal mutualist as a factor for the ambrosia complex becoming a pest.