Diaporthe cotoneastri and Ilyonectria cyclaminicola Endophytes Promote the Growth, Development, and Accumulation of Active Components of Epimedium Host Plants

Abstract Epimedium plants offer a source of medicinal ingredients. To promote research and development of Epimedium in Korea, we explored the effects of endophytes on host plant growth and development and the accumulation of active components. The effects of the endophytes Diaporthe cotoneastri (strain S3) and Ilyonectria cyclaminicola (strain S10) on the biomass, photosynthesis parameters, chlorophyll fluorescence parameters, and activity of key enzymes and active components during the growth and development of Epimedium were investigated. Both the S3 and S10 strains promoted the growth of Epimedium grown in the natural environment in a field experiment in Korea. Redundancy analysis showed that the content of epimedin A and peroxidase activity were positively correlated with the total flavonoid content. The S10 strain promoted the growth of Epimedium faster than the S3 strain. The results suggested that flavanone 3-hydroxylase catalyzes the synthesis of epimedin A and icariin by different pathways from the same substrate, although the mechanism remains unclear. Overall, these findings suggest that peroxidase plays a key role in total flavonoids synthesis in Korean Epimedium. These results can support the use of these endophyte strains as biological fertilizers to improve the growth and active components production of Epimedium. Keywords: F3H; endophyte; Korean Epimedium; total flavonoids; epimedin A; icariin