宁夏枸杞根腐病不同发病时期根区土壤AMF群落变化规律

AMF community in the root zone soil at different stage of Lycium barbarum root rot disease

根腐病是宁夏枸杞毁灭性病害,丛枝菌根真菌(AMF)能通过与植物共生提高植物对病原菌的抗性,探明根腐病发生与宁夏枸杞根区土壤AMF的关系是应用AMF防控宁夏枸杞根腐病的基础。采用湿筛倾析法和染色法分析宁夏枸杞根腐病不同发病时期根区土壤理化性质、AMF群落组成、孢子密度、定殖率等,旨在揭示宁夏枸杞根腐病不同发病时期根区土壤AMF群落变化规律。结果表明:随着根腐病发病程度的加重,宁夏枸杞根区土壤全氮含量增高,全钾、速效钾含量降低;AMF孢子密度先增加后降低,发病前期和中期比未发病和发病后期增加了31.32%~49.48%;AMF定殖率、易提取球囊霉素相关土壤蛋白含量、总球囊霉素相关土壤蛋白含量增加,均在发病中期和后期达到最高;α-多样性指数先升高后下降,以发病前期最高;球囊霉属AMF和无梗囊霉属AMF多度在所有发病时期均低于未发病,隔球囊霉属刚好相反,根孢囊霉属则是先增高后降低。在宁夏枸杞根区土壤降氮增钾,接种球囊霉属和无梗囊霉属AMF可能防控根腐病发生。

Root rot disease is a devastating disease of Lycium barbarum.Arbuscular mycorrhizal fungi(AMF)affect plant resistance to phytopathogens through symbiosis with plants.The relation of root rot disease and AMF is the foundation on the application AMF to control Lycium barbarum root rot disease.In this paper,it is aimed that revealing the change rule of AMF community in the root zone soil of at different stage of Lycium barbarum root rot disease through investigating the AMF community,spore density and infection rate in the root zone soil at different stage of Lycium barbarum root rot disease were with wet-sifting and staining root methods.The results showed that with the aggravation of root rot disease,the total nitrogen content increased and the total potassium and available potassium decreased in root zone soil of Lycium barbarum.Meanwhile,the density of AMF spores firstly increased and then decreased.The density of AMF spores in the early stage and middle stage increased by 31.32%~49.48%compared with the health stage and the later stage.The infection rate of AMF,easily extractable glomalin related soil protein and total glomalin related soil protein increased and the value in the middle stage and later stage were the highest.Theα-diversity index of AMF community increased firstly and then decreased,and were the highest in the early stage.Moreover,after the root rot disease happened,the abundance of genus Glomus and Acaulospora decreased and the abundance of Septoglomus increased.The abundance of Rhizophagus increased firstly and then decreased.It is used to control Lycium barbarum root rot disease that control nitrogen and increase potassium and inoculation genus Glomus and Acaulospora in root zone soil of Lycium barbarum.