Alkaloid Contents in Epichloe Endophyte-Infected Elymus tangutorum Sampled along an Elevation Gradient on the Qinghai-Tibetan Plateau

Alkaloids produced by endophytic fungi can have an important influence on agricultural ecology, and can often be affected by climatic factors. At present, there are no studies that have assessed the relationship between alkaloid production and elevation or climatic factors in the Qinghai-Tibetan Plateau. To address this knowledge gap, we explored ergot alkaloid and peramine production in Epichloe-infected (E+) Elymus tangutorum collected from the Qinghai-Tibetan plateau and assessed the relationship between the concentration of these alkaloids and elevation. The effects of temperature and precipitation on these relationships were also investigated. The concentrations of ergonovine, ergine, and peramine ranged from 0.47-0.84, 0.35-1.72 and 9.18-13.00 mu g center dot g(-1), respectively. Fitted cubic regression curves describing an arc-pattern across the elevational series were statistically significant for ergine and peramine concentrations. The elevational trend in peramine concentration was linked to mean daily temperature, while the ergine elevational trend was linked to mean precipitation. Our results provide a new understanding of the climatic factors that influence the alkaloid production of endophytic fungi at different elevations in the Qinghai-Tibetan plateau.