Diaporthe cotoneastri and Ilyonectria cyclaminicola endophytes promote the growth, development, and accumulation of active components of Epimedium koreanum Nakai host plants in field experiments

Abstract Purpose This study aims to explore the effects of two endophytes of Epimedium koreanum Nakai on host plant growth and development and medicinal material quality and to promote the growth and development of ingredients derived from Epimedium koreanum Nakai . Methods The effects on the biomass, photosynthesis parameters, chlorophyll fluorescence parameters, activity of key enzymes, and active components in the process of growth and development in Korea were examined. Results From the analysis of biomass and photosynthesis data, both the S3 ( Diaporthe cotoneastri ) and S10 ( Ilyonectria cyclaminicola ) strains promoted the growth of Epimedium koreanum Nakai . Redundancy analysis (RDA) showed that the activity of S3 and the content of epimedin A were negatively correlated and that the peroxidase (POD) activity was positively correlated with the total flavonoid content. Conclusion The application of the S3 ( Diaporthe cotoneastri ) and S10 ( Ilyonectria cyclaminicola ) strains can significantly increase the biomass and contents of total flavonoids, icariin, epimedin B, and epimedin C, but not epimedin A, in Epimedium koreanum Nakai host plants grown in field conditions. The S10 strain promotes faster growth of Epimedium koreanum Nakai than the S3 strain, and flavonoid 3-hydroxylase (F3H) catalyzes the synthesis of epimedin A and icariin by different pathways using the same substrate. POD plays a key role in total flavonoid synthesis in Epimedium koreanum Nakai .