EFFECTS OF TWO AMF ON PHYSIOLOGICAL INDEXES AND SOIL ENZYME ACTIVITIES OF PUCCINELLIA TENUIFLORA SEEDLINGS UNDER SALT (NaCl) AND ALKALI (NaHCO3) STRESS

摘要

Puccinellia e-nuiflora is a kind of high quality forage with excellent salt tolerance. In this study, Puccinellia tenuiflora were chosen as the experimental material and the arbuscular mycorrhizal fUngi was inoculated which was identified as the dominant fungi from Puccinellia tenuiflora rhizo- sphere in Songnen saline-alkali grassland in the early research work. Puccinellia tenuiflora was given salt (NaCl) and alkali (NaHCo3) stress respectively with the concentration of 0, 100 mM, 200 mM, 300 mM and 400 mM to reveal the effect of AM fungi on their physiological indexes and soil enzyme activities under greenhouse culture conditions. The result showed that the inoculation of F-unneliformis mosseae and Rhizophagus intraradices could both significantly improve the salinity tolerance of Puccinellia tenuiflora and the enzyme activities of its rhi- zosphere soil, while the two types of inoculation under saline-alkali stress showed different promotion effect. In general, the promotion effect of Rhizophagus intraradices on the physiological index and soil enzyme activities was much more obvious than that of Funneliformis mosseae, besides, even in the high concentration of salt and alkali, the AM fungi were also effective. The different characteristics of Puccinellia tenuiflora at different concentrations of salt and alkali may be caused by the different tolerance mechanisms of Puccinellia tenuiflora in the two different conditions. Different AM fungi also played different roles in regulating the metabolic pathway of Puccinellia tenuiflora. This study has some significance to improve the quality of pasture and remediate the salinized soil with mycorrhizal technology, and provide the theoretical basis for improving the development of animal husbandry in saline-alkali area.