Molecular diversity of arbuscular mycorrhizal fungi in Prunus africana, an endangered medicinal tree species in dry Afromontane forests of Ethiopia

The molecular diversity of arbuscular mycorrhizal (AM) fungi colonizing roots of Prunus africana and of AM fungal spores obtained from baiting cultures of indigenous soils from two dry afromontane forests of Ethiopia was investigated. The internal transcribed spacer (ITS) rDNA region from colonized roots and single spores of three AM fungal spore types was amplified, cloned and sequenced using AM fungal specific primers. Phylogenetic analysis using the 5.8S rDNA data set revealed that 109 of the sequences obtained belong to members of the Glomeromycota. Subsequent 5.8S/ITS2 rDNA sequence analysis indicated high AM fungal diversity and dominance of Glomus types. Twenty sequence types belonged to the Glomeraceae and one each to the Diversisporaceae and Archaeosporaceae. Two of the three spore types were identified as Glomus etunicatum and Glomus mosseae. Twenty of the AM fungal types identified are new to Ethiopia and to science. The AM fungal community differed between the two sites studied.