Effects of endophytic fungi(Paecilomyces sp.)on the salt tolerance of Salix integra
The rehabilitation and reclamation of coastal saline-alkali land is of great significance since it is regarded as a reserve resource for cultivated land.Biological soil amelioration is an effective means of improving soil quality in saline-alkali land and focuses on improving the adaptability of plants to saline environments.In this study,an endophytic fungus(Paecilomyces sp.)isolated from the roots of a coastal plant was inoculated into the roots of Salix integra seedlings.The potential of this strain to promote plant growth under salt stress was explored,and the relevant mechanisms are discussed.The effects of inoculation with Paecilomyces sp.on the growth,physiology,and photosynthetic indices of Salix integra under salt stress were compared.Gene expression differences in the leaves of Salix integra before and after inoculation with Paecilomyces sp.were analyzed.Compared with the control group without inoculation,root length,root surface area,and root volume of Salix integra in the treatment group(inoculated with Paecilomyces sp.)were significantly increased by 163.4％,72.4％and 96.4％,respectively;the catalase(CAT)activity,indole-3-acetic acid(IAA)concentration,and core chlorophyll fluorescence parameters(photosystem Ⅱ actual photochemical quantum efficiency(ΦPSⅡ),photochemical quenching coefficient(qp),and electron transportation rate(ETR))in leaves were significantly enhanced(P＜0.05).Under salt stress,701 differentially expressed genes(DEGs)were identified in the leaves of Salix integra before and after endophytic fungus inoculation,according to transcriptome data.They were mainly enriched in phenylpropane biosynthesis,plant-pathogen interactions,plant hormone signal transduction,starch/sucrose metabolism,and other pathways.Among the Kyoto Encyclopedia of Genes and Genome(KEGG)pathways,the upregulated DEGs were significantly enriched in plant hormone signaling pathways.Gene function analysis indicated that genes annotated in the jasmonic acid-,ethylene-,auxin-,and cytokinin signaling and brassinol biosynthesis pathways play an important role in the regulation of salinity tolerance by Paecilomyces sp.In summary,this endophytic fungus strain(Paecilomyces sp.)can effectively alleviate the adverse effects of salt stress on the growth and photosynthesis of Salix integra seedlings.
万方数据
维普
