Abstract: Soil salinization results in the slow growth of plants,and even inhibits their normal development. How to eliminate the adverse influences of high salinity and high pH on the growth and productivity of plants in saline-alkali land has become a key issue in agricultural sustainable development. Recently,some great benefits of endophytes and symbiotic fungi in salt and alkali resistance of host plants have been arousing great interest among scientific community. In this paper we summarized the advances on the effects of endophytic fungi on salt and alkali tolerance of host grasses. Firstly,we reviewed the impacts of endophytic fungi on the seed germination and growth of host grasses under salt-alkali stress,i.e.,increasing the seed germination rate,accelerating the growth of germ and radicle,and improving the tiller number,leaf number,plant height,biomass,root-shoot ratio,mature inflorescence length,seed number and seed production of host grasses. While as there were no promoting effects among some grasses infected by endophyte under salt stress. Secondly,we reviewed the roles of endophytic fungi in terms of reducing the original salt injury of host grasses in salt and alkali stresses,such as affecting the membrane permeability,improving photosynthesis,increasing water use efficiency,changing the nutritional metabolism and ion poisoning,and impacting the metabolism of plant hormones. Finally,we summarized the roles of endophytic fungi in reducing secondary salt damages to the host grass;endophytic fungi promoted the secretion of antioxidants in grasses,increased the activity of antioxidant enzymes,and adjusted the contents of the organic osmotic substances. This review systematically summarized the relevant research achievements on the endophytic fungi and the salt and alkali resistance of host grasses,brought up possible future research questions and approaches,and may provide references for later research.

Key words: endophyte, salt stress, alkali stress, stress resistance