Virulence and genetic diversity among Fusarium oxysporum f. sp. carthami isolates of India using multilocus RAPD and ISSR markers

Abstract

Safflower wilt, incited by Fusarium oxysporum f. sp. carthami (Foc) is one of the most devastating diseases of safflower. Virulence and genetic diversity of 90 Foc isolates representing four major safflower growing states (Maharashtra, Karnataka, Telangana, and Madhya Pradesh) in India were analyzed. Out of 45 RAPD and 45 ISSR primers screened, 17 of each RAPD and ISSR markers revealed a comprehensive picture of genetic diversity. Primers depicting maximum heterozygosity, effective number of alleles, and Shannon information index were identified. Cluster and principal coordinate analyses distributed isolates from a given state among different clusters and quadrants, respectively, indicating high genetic diversity. However, certain region-specific groupings within clusters were found. The population structure comprised two sub-populations with admixture of alleles. AMOVA indicated maximum molecular variation within states (95%), and within races (79%). Among the six races identified on the basis of disease reactions on differential cultivars, Race 6 was the most virulent and Race 2 as the most prevalent. Groupings on the basis of molecular markers and geographical origin showed some degree of concurrence with the virulence of isolates. The findings are useful in screening of newly developed pathogen resistant varieties for the deployment of regionspecific resistant cultivars of safflower.

Genotyping of Russian isolates of fungal pathogenTrichophyton rubrum, based on simple sequence repeat and single nucleotide polymorphism

“…The AMOVA analysis showed relatively high proportion of variability, explained by the division of T. rubrum sample into ST1 and ST2 groups, 22-48% depending on the distance metrics. It was not less, than in other studies on clonal filamentous ascomycetes with 19-21% of variability between groups 46,47 or filamentous ascomycetes with mixed reproduction mode, with 2-13% of total variability explained by differences between intraspecific groups. 48,49 Intraspecific genetic lines in fungi sometimes demonstrate restricted geographic ranges.…”

Genotyping of Russian isolates of fungal pathogen Trichophyton rubrum, based on simple sequence repeat and single nucleotide polymorphism

“…The AMOVA showed relatively high proportion of variability explained by the division of T rubrum sample into ST1 and ST2 groups, 22%‐48% depending on the distance metrics. It was not less than in other studies on clonal filamentous ascomycetes with 19%‐21% of variability between intraspecific groups 46,47 or filamentous ascomycetes with mixed reproduction mode, with 2%‐13% of total variability explained by differences between intraspecific groups 48,49 …”

“…For this species, our earlier work seemingly represented the first successful attempt to obtain congruent results by two independent molecular strain typing techniques. 16 46,47 or filamentous ascomycetes with mixed reproduction mode, with 2%-13% of total variability explained by differences between intraspecific groups. 48,49 Intraspecific genetic lines in fungi sometimes demonstrate restricted geographic ranges.…”

Differentiation between Tomato Fusarium Wilt Isolates by ISSR Markers and Virulence Analysis

“…Differences in ISSR polymorphism were also found in Fusarium strains isolated from either cabbage or tomato (Troncoso-Rojas et al, 2013). Singh et al (2019) reported high genetic diversity in 90 isolates of F. oxysporum f. sp. carthami isolated from Safflower using 17 polymorphic RAPD and ISSR primers.…”