"atractylodes lancea" is a medicinal herb that grows in central china. "a. strictum" acts as a fungal endophyte and interacts with "a. lancea" in drought conditions and confers tolerance in moderate drought. under mild drought conditions, "a. strictum" enhanced leaf soluble sugars, proteins, proline and antioxidant enzyme activity, which decreased the degree of plasmalemma oxidation. this increased "a. lancea" abscisic acid level and root:shoot ratio. while "a. strictum" may alleviate the effects of a mild to moderate drought, benefits of this endophytic relationship are constrained by drought degree, as there were no significant effects of "a. strictum" on "a. lancea" during periods of regular watering or severe drought.