Multilocus molecular phylogenetic-led discovery and formal recognition of four novel root-colonizing Fusariumspecies from northern Kazakhstan and the phylogenetically divergent Fusarium steppicolalineage

ABSTRACTIn this study, DNA sequence data were used to characterize 290 Fusariumstrains isolated during a survey of root-colonizing endophytic fungi of agricultural and nonagricultural plants in northern Kazakhstan. The Fusariumcollection was screened for species identity using partial translation elongation factor 1-α (TEF1) gene sequences. Altogether, 16 different Fusariumspecies were identified, including eight known and four novel species, as well as the discovery of the phylogenetically divergent F. steppicolalineage. Isolates of the four putatively novel fusaria were further analyzed phylogenetically with a multilocus data set comprising partial sequences of TEF1, RNA polymerase II largest (RPB1) and second-largest (RPB2) subunits, and calmodulin (CaM) to assess their genealogical exclusivity. Based on the molecular phylogenetic and comprehensive morphological analyses, four new species are formally described herein: F. campestre, F. kazakhstanicum, F. rhizicola, and F. steppicola.