Molecular differences distinguish clonal lineages within East African populations of Fusarium oxysporum f.sp. cubense

Abstract

E .M . L O DW IG , P. D. B RI DG E , M .A . RU TH E RF OR D , J . K U NG 'U A ND P. J EF FR I ES . 1999. Molecular approaches for the assessment of intraspecific diversity within an economically important plant pathogen were compared with traditional physiological methods (vegetative compatibility testing). The vegetative compatibility groups (VCGs) of 14 isolates of Fusarium oxysporum f.sp. cubense (FOC) from Kenya were first assessed using nitrate non-utilizing mutants. Nine of these isolates, from different areas of the country, were compatible with one or more of VCGs 0124, 0125, 0128 and 01220, i.e. they formed a single clonal lineage. Three isolates, all originating from the banana growing district of Kisii, were compatible with the VCG 01212 and formed a second distinct clonal lineage. Mutants could not be recovered from one isolate (62) and two isolates (27 and 30) were not vegetatively compatible with any of the VCG testers and may represent two novel VCGs. Polymerase chain reaction (PCR) fingerprinting, especially when using the M13 derived primer, was found to produce banding patterns that correlated with clonal lineage and also distinguished isolates 27 and 30 when analysed by unweighted pair group method analysis and principle co-ordinate analysis. This approach also distinguished FOC from F. oxysporum IMI350438 isolated from Triticum sp. and from isolates of Colletotrichum gloeosporioides. Total protein profiles were analysed by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and although clonal lineages were not separated, isolates 27 and 30 were again distinguishable and FOC produced a different profile to F. oxysporum (IMI 350438) and C. gloeosporioides.

The distribution and host range of the banana Fusarium wilt fungus, Fusarium oxysporum f. sp. cubense, in Asia

“…The widespread occurrence could be due to human dispersal of planting material. VCG 01220, for example, which is commonly found throughout the Indian subcontinent, is also found in East and Central Africa (ECA) [ 65 ], a region with a well-established relationship with India. Fusarium wilt was discovered in ECA when a large community of Indian emigrants settled in the area soon after World War II ended [ 66 ].…”

The development of a multiplex PCR assay for the detection of Fusarium oxysporum f. sp. cubense lineage VI strains in East and Central Africa

“…Pathogenicity testing and VCG analysis, however, are laborious and time consuming. Disease development is also influenced by the environment, while VCG analysis requires the availability of (Bentley et al 1998;Lodwig et al 1999;Mostert et al 2017;Karangwa et al 2017). The markers developed in this study, therefore, present a valuable tool that can be used to speed up the identification of Foc Lineage VI strains and to guide the management of banana Fusarium wilt in ECA.…”

Molecular characterization ofRhizoctonia solaniisolates the incitant of soybean root rot

“…Nevertheless, isolates consisting of one particular AG or subgroup had a similar banding pattern, although they represented different geographical regions, host plants, or pathogenicity. Moreover, Lodwig et al (1999) showed that although clonal lineages of Fusarium oxysporum were not separated using total protein profiles analysed by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE), two isolates were distinguishable. Mohammadi et al (2003) used total soluble protein profiles and isozyme analysis to measure the genetic diversity of the Iranian R. solani isolate AG1.…”