Effects Of Arbuscular Mycorrhizal Fungi On The Growth Of Elaeagnus Angustifolia Seedlings Under Saline - Alkali Stress

Salinization of soil is a resources and ecological environment problem which is an urgent need to address global challenges. Northeastern Plains is one of distribution area saline soil. Through the introduction of E.angustifolia. L that pre-planted in Heilongjiang province, the study has found mycorrhizal E. angustifolia. L could grow well in severe saline. The effects of arbuscular mycorrhizal fungi(AMF), Glomus intraradices(GI), Glomus mosseae(GM) on growth, physiological indicators of Elaeagnus angustifolia L. under four kinds of salinity stress were studied in potted culture experiments. The purpose is to reveal physiological mechanism of the mycorrhizal under salinity stress. The main research results were as follows:1. In this experiment, two kinds of mycorrhizal fungi could establish a symbiotic relationship with Elaeagnus angustifolia L., compared to G. mosseae treatment, colonization of G. intraradices were significantly high, while with the increase in soil salinity, mycorrhizal colonization rates were decreased.2. The salt stress significantly reduced plant height, stem diameter, total biomass dry weight, chlorophyll content and photosynthetic characteristics, while increased the contents of proline and MDA. Na+ concentrations in roots and leaves were increased, K+ concentrations and K+/Na+ ratio in roots and leaves were decreased.3. The height of Elaeagnus angustifolia. L significantly increased by AMF(GI and GM) compared with non-mycorrhizal, the rate were 20.07%, 9.68%, respectively, and the same to height, leaf dry weight were increased 43.88%, 15.52%, respectively. The net photosynthetic rate(Pn), transpiration rate(Tr), stomatal conductance(Gs), intercellular CO2 concentration(Ci) were significantly higher than non-inoculated AM fungi(p<0.05). This implies that AM fungi significantly increased chlorophyll content and photosynthetic physiological characteristics of Elaeagnus angustifolia. L. In severe salinity stress inoculation GI and GM compared with non-mycorrhizal plants the activity of SOD in leaves was increased, the rate were 29.66%, 20.21%, and was decreased by 15..68%, 11.14% in the leaves; The activity of CAT in leaves was increased by 14.25%, 11.14%, and was decreased by 14.25%, 11.69% in the leaves; The activity of POD in leaves was increased by 27.94%、5.93%, and was decreased by 15.77%, 14.30% in the leaves. The content of MDA was decreased by 31.0%, 26.4% than non-inoculated AM fungi in the roots, and was decreased by 19.68%, 16.38% in the leaves. The content of proline was decreased by 23.45%, 10.29% in AM compared with non-mycorrhizal plants in the roots, and was decreased by 36.86%, 29.42% in the leaves.Leaf Na+ concentrations were significantly decreased, but leaf K+ concentrations and K+/Na+ ratio were increased when seedlings with both GI and GM.4. Inoculated with G. intraradices was significantly higher than inoculated with G. mosseae in all kinds of physiological response indicators. Our research showed that G. intraradices has a good promotion prospect in saline improvement.In conclusion, inoculated with AMF could alleviate the growth limitations imposed by saline conditions, and thereby play a very important role in promoting plant growth under salt stress in Elaeagnus angustifolia L..