Soil Properties Shape Species Diversity and Community Composition of Native Arbuscular Mycorrhizal Fungi in Retama raetam Roots Growing on Arid Ecosystems of Tunisia

The aim of this study was to identify the major environmental factors affecting the Arbuscular Mycorrhizal Fungi (AMF) diversity and community composition in the roots of Retama raetam growing on arid ecosystems of Tunisia AM Fungi were assessed by cloning and sequencing of the AMF SSU rRNA gene and therefore checked against NCBI GenBank and MaarjAA4 database. Thirteen operational taxonomic units (OTUs) were identified in R. raetam roots and AMF community was dominated by Glomeraceae. Of the totality of OTUs, ten matched previously known virtual taxa (VTX) and 3 OTUs were treated as novel VT and grouped into 3 putative new AMF taxa (pNTX). Correlation analysis reported that high available phosphorus content and high electrical conductivity in the soil decrease AMF richness and diversity. Interestingly, Principal Component Analysis (PCA) and Monte Carlo permutation tests on Canonical Correspondence Analysis (CCA) indicated that soil physic-chemical properties such as soil total nitrogen (TN), soil-available P, EC, and soil texture affected the AMF community composition. No significant relation was found between AMF distribution and soil organic carbon (OC) and soil pH. Our findings provide insights into the nature of AMF communities colonizing R. raetam roots and help to link fungal distribution to specific soil properties, which could be exploited in the identification of a wider variety of fungal strains as potential inoculants for rehabilitation and restoration program. (C) 2020 Friends Science Publishers