Endophytic fungi specifically introduce novel metabolites into grape flesh cells in vitro

Since endophytes can affect metabolism of host plants, they are expected to be used to improve crop quality, especially for crops with organoleptic sensitive products such as wine grape. However, details of metabolic interactions between endophytes and host plants were less understood. In this work, we used high pressure liquid chromatography (HPLC) to analyze the metabolites of fruit flesh cells of grape treated with dual culture of different endophytic fungal strains (EFS). We observed that the dual-culture with different fungal strains show different metabolites composition in grape cells. In response to different EFS, quantities of detected metabolites in grape cells varied from 6 to 17 in this assay, and 1 to 11 novel metabolites were introduced into metabolome of grape cells. Dual-culture with fungal strains CS2, RH16 and RH5 introduced the highest quantities (10 or 11) of novel metabolites in grape cells. More importantly, the modification of metabolic profiles in grape cells via fungal endophytes appeared to be fungal strain/genus-specificity. Overall, this work revealed that introduction of specific metabolites in host plants may be one consequence during the process of endophytes-host metabolic interactions, which raise the possibility to shape grape qualities and characteristics using tool of fungal endophytes.