Population structure and pathogenicity of members of the Fusarium oxysporum complex isolated from soil and root necrosis of pea (Pisum sativum L.)

Abstract

Forty-nine strains of the Fusarium oxysporum complex were isolated from five different sample locations within two neighboring pea fields. Of these, 39 strains were isolated from soil and 10 from pea plants showing symptoms of root rot. Twenty-eight of the isolates were tested for pathogenicity towards pea. Based on percentage discoloration of the roots and stem base, the isolates were divided into three groups: seven strains were pathogenic, 14 strains were weakly pathogenic, and seven strains were non-pathogenic towards pea. To assess the genetic relatedness of all 49 strains, gene genealogies were constructed from aligned DNA sequences from part of the translation elongation factor, nitrate reductase, beta tubulin, and mitochondrial small subunit rDNA. Maximum parsimony analysis of the combined data set yielded a single most-parsimonious tree containing three strongly supported clades which may represent cryptic species. No correlation was observed between the multigene phylogeny and pathogenicity toward pea, strain geographic origin and substrate (soil or plant) from which the strains were isolated. Strains that were non-pathogenic, weakly pathogenic or pathogenic sometimes shared the same multilocus genotype. These results suggest that strains pathogenic and putatively non-pathogenic to pea are very closely related genetically.

Genomic Characterization and Virulence Potential of TwoFusarium oxysporumIsolates Cultured from the International Space Station

“…Based on EF-1α phylotyping, F. oxysporum can be divided into 3 distinct clades with various clonal lineages within each clade (22, 23). The phylogenetic tree inferred in Fig.…”

Roots of symptom-free leguminous cover crop and living mulch species harbor diverse Fusarium communities that show highly variable aggressiveness on pea (Pisum sativum)

“…For example, F . oxysporum isolates from diseased pea roots in North Dakota were only weak pathogens on pea [ 25 ], while in Scandinavia some highly aggressive isolates were found, which induced severe root rot and wilt symptoms in greenhouse bioassays [ 73 , 23 ]. Arias et al [ 74 ] reported similar results for the growth and yield of soybeans after root inoculation with F .…”

Alarming occurrence of Fusarium wilt disease in pea (Pisum sativum L.) cultivations of Jabalpur district in Central India revealed by an array of pathogenicity tests

“…In a study evaluating root rot of pea, thirty nine strains of Fusarium oxysporum were isolated from soil and ten strains were isolated from pea plants showing root rot from five locations on two neighbouring fields of pea. Twenty one of these were found to be pathogenic to pea (Skovgaard et al, 2002). These figures indicate the severity of Fusarium diseases on pea cultivations.…”