AMF diversity in citrus rhizosphere

Abstract

Microbial diversity in any soil is considered as bio-indicator towards the maintenance of soil ecosystem service. Citrus is one of the most widely grown commercial fruit crops and is heavily dependent on arbuscular mycorrhizal fungi (AMF). In the proposed work, small subunit ribosomal RNA (SSU rRNA) was used to identify the AMFdiversity in roots and rhizospheric soils of 29-yr-old Satsuma mandarin (Citrus unshiu Marc) grafted on trifoliate orange (Poncirus trifoliata L.). As many 193 and 190 operational taxonomic units (OTUs) were observed in the SSU rRNA clone library of plant roots and soils. Soil native mycorrhizal fungi mostly colonized citrus roots, because 178 OTUs co-existed in both plant roots and soils. While, Glomus was predominant in roots, and Claroideoglomus and Glomus were examined in rhizosphere. In the species levels, the clone, Glomus Glo20, had the highest relative and read abundance in all the root and soil samples than other clones. As many, four soil samples were grouped with higher taxonomic similarity with the database sequences compared to root samples. These results provide the new perspectives at the molecular level to highlight the community of AMF in citrus.