Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Titre : Species Diversity and Drought Tolerance of Dark Septate Endophytes Fungi in Desert Plants

Auteur : 胡倩楠

Grade : Master 2022

Université : Hebei University

Résumé partiel
Dark septate endophytes（DSE）are ascomycetes or asexual fungi that colonize the cortex cells of plant roots and form dark septate hyphae and microsclerotia.Reaumuria soongorica,Sympegma regelii,Ephedra przewalskii,Nitraria sphaerocarpa and Salsola passerina as pioneer species in the process of restoring drought habitat,play an important role in preventing wind,controlling sand and maintaining ecological stability.Based on the symbiosis between desert plants and DSE,this study collected root and soil samples of 5 extremely arid desert plants at different times to study the species diversity of DSE and the formation characteristics of DSE and plant symbiosis.In vitro,the optimum p H,carbon and nitrogen sources and drought tolerance of DSE fungi were analyzed.Influence of DSE on growth and drought resistance of Astragalus adsurgens was investigated by artificial inoculation in laboratory,so as to explore the ecological function of DSE and its application potential in promoting the restoration of desert vegetation.The main test results were as follows:1.The roots of R.soongorica,S.regelii,E.przewalskii,N.sphaerocarpa and S.passerina were colonized DSE and the colonization rates were significantly affected by plant and month.The colonization rates of mycelia,microsclerotia,total colonization rate and total colonization intensity were 35.13 %-71.17 %,21.11 %-56.67 %,44.18 %-78.58 % and 14.89 %-48.96 % in3 months,respectively.DSE colonization of E.przewalskii was the lowest in July,the S.regelii colonization of DSE was the highest in September,and the highest colonization of DSE in December was S.passerina.The DSE colonization degree of 5 extremely arid desert plants in July were higher than that in December.2.DSE colonization rates were significantly related to soil factors.Available P had significant negative impacts on the rate of mycelial,microsclerotia,total colonization and total colonization intensity.The soil organic carbon only had significant adverse effects on total colonization intensity.Alkaline phosphatase had significant positive impacts on microsclerotia colonization rate.

Mots clés : Dark septate endophytes ;Species diversity ;Extremely arid desert plant ;Astragalus adsurgens ;Biological adaptation ;

Présentation (CNKI)