Arbuscular mycorrhizal fungi population diversity of rhizosphere soil and root system in potato field in central Inner Mongolia

Abstract:

[Background] Arbuscular mycorrhizal fungus (AMF) is the most widely distributed fungi in mycorrhizal fungi. They can form mycorrhizal symbiosis with more than 90% of the plants, and enhance the resistance of plants by regulating metabolic activities in the host. [Objective] To reveal the structure and composition of AMF in soil of main potato producing areas in Inner Mongolia, and analyze the effects of different development stages of potato and continuous cropping on AMF groups. [Methods] Using root and rhizosphere soils of potato collected from Dajing, Xumayao and Honggeertu villages in central of Inner Mongolia as material, though PCR amplification and establishing 18S rRNA gene library, try to study the effect on AMF composition and diversity in potato rhizosphere soils and root at different locations, different growth stage and continuous croping plot. [Results] AMF diversity of rhizosphere soil in Dajing village and Honggeertu village was more than that in Xumayao village, the dominant strain was Glomus in both Dajing village and Honggeertu village, while Diversispora was the dominant strain in Xumakuo village. In roots, the results of AMF diversity showed that there was no significant difference among three areas, but the proportion of AMF population was different. Diversispora was the dominant strain in Dajing village, Rhizophagus was the dominant strain in Honggeertu village and Xumayao village. The AMF diversity of potato rhizosphere soil in seedling stage and tuber swelling stage were more than that in tuber formation stage at the same area, Glomus was the dominant strain in the three stages, while in root the Rhizophagus was the dominant strain in the three stages. After 2015 and 2016 continuous cropping potato in Dajing village, the types of AMF populations in rhizosphere soil and root were identical, but the relative abundance of different AMF populations changed significantly. Among the rhizosphere soil samples, the relative abundance of Glomus and Archaeospora population increased with continuous cropping, and the relative abundance of Entrophospora and Diversispora decreased. But the dominant population of AMF in root samples changed from Glomus to Rhizophagus with continuous cropping. This result indicated that the effect of continuous cropping on AMF diversity in rhizosphere soil was significantly higher than that in root. [Conclusion] The diversity of AMF population varies with soil composition, potato growth period and cropping effect.

Key words:Solanum tuberosum L., Arbuscular mycorrhizal fungus, Community diversity