Objective The study was conducted to explore the effects of endophytic fungi on phosphorus uptake in Mytilaria Laosensis seedlings under low phosphorus stress, and to select the endophytic fungi that could promote the growth and phosphorus uptake in M. Laosensis seedlings.

Method Taking M. Laosensis seedlings as the research object, 10 strains (M1, M2, M3, M4, M5, M6, M7, M8, M9, M10) were inoculated by the method of irrigating bacterial solution. Fifteen days later, low phosphorus stress test (18, 12, 6, 0 mg/kg) was conducted, after sixty days of low phosphorus stress, the height and ground diameter, the root dry weight and the phosphorus content of the shoots and roots of plants, the acid phosphatase activity in leaves and roots and rhizosphere soil were measured to explore the growth and phosphorus uptake of M. Laosensis.

Result With the increase of stress degree, strain M9 and M10 could increase the height, ground diameter and root-shoot ratio of M. Laosensis and promote its growth. Under normal conditions and severe stress, strain M6 could effectively increase the phosphorus content in shoot of M. Laosensis by 36. 9% and 41. 1%, respectively. With the increase of stress degree, strain M9 had a more prominent effect and strain M4 could significantly increase the phosphorus content in the root of M. Laosensis, which increased by 57.7% under severe stress. Under severe stress, both strains M6 and M9 could significantly increase the acid phosphatase activity in leaves of M. Laosensis and soil; except for mild stress, the acid phosphatase activity of the root system of M. Laosensis treated with the strain was significantly higher than that of CK.

Conclusion Under soil phosphorus stress, inoculation of endophytic fungi has a significant effect on the growth and phosphorus uptake of M. Laosensis. Under different stress environments, strains M6 and M9 can increase phosphorus content, acid phosphatase activity and superoxide dismutase activity in M. Laosensis to a certain extent and promote seedling growth efficiently.