The Symbiotic Diversity Of Arbuscular Mycorrhizal In Salinized Leymus Chinensis Grassland In Western Jilin Province

It has been reported that about seven percent of global soil area is covered by salinesoil.The area of saline soil in China approciately approached to 9.9×107hm2.The grassland inwester Jilin province is one of the grassland which has better conditions.At present , Leymuschinensis grasslands are the dominating grasslands remained in this region,but they have beenalkali- saline seriously,because of the abusing of grassland and undue grazing.All these thingsobstruct the development of stockbreeding and the protection of ecological environment.Thusit is of great important to study the methods to make better use of Leymus chinensisgrasslands .AM fungi is one of the popular fungi existing in nature, their combinations withplants can promote the hosts to absorb more nourish elements,and improve their resistance toarid and diseases.It has been reported that there are a great deal of AM fungi in saline soil,andmany ecological factors effet their formation,growth.AM fungi can stimulate the plants'growth and absorbtion of nutritions,thus improve their abilities of resisting to salt condition. The resources of AM fungi in Leymus chinensis grassland of western Jilin Province wereresearched in April and Autumn,and twenty-nine species of AM fungi belonging to genusAcaulospora, Gigaspora,Glomus,Paraglomus and Scutellospora, respectively were identifiedfrom 20 typical plant species in this region.Their morphologica descriptions were givenminutely. Among the AM fungi in the grassland of western Jilin Province,the spcies numberof Glomus was superiority(accupying 75.9% of total number),then was Acaulospora(13.8%).The frequencies of Glomus mosseae,Glomus etunicatum et. al were higer,which may be thedominant fungi in this area. The developments and infections of AM fungi were related to the type of the hosts.All ofthe 20 plants researched could be infected by AM fungi,excepting Carex duriusula inspring(while in autumn it was found).The colonization rates showed great variety, and thehighest level were observed in Vicia amoena(94.12%), while in Carex duriusula et al werelower. Different AM fungi species were found except for alkaline zone where no plant canlive.Spore densities of different small plant communications were notably different. Inautumn, the spore densities of Leymus chinensis,Arundinella hirta and Vicia amoena were higher,while the lowest one was found around Carex duriusula.It was also found that colonization ratesand spore densities weren't correlate in spring, while they were correlate in Autumn.Seasonaltransformation affected the colonization rates and spore densities,and the average value ofthese two number were higer in Autumn than in Spring.