Characterisation of Alternaria species-groups associated with core rot of apples in South Africa

Simple item page
dc.contributor.authorSerdani M.
dc.contributor.authorKang J.-C.
dc.contributor.authorAndersen B.
dc.contributor.authorCrous P.W.
dc.date.accessioned2011-05-15T15:57:24Z
dc.date.available2011-05-15T15:57:24Z
dc.date.issued2002
dc.description.abstractAlternaria core rot of red apple cultivars is a serious post-harvest disease in South Africa. Thirty isolates of Alternaria spp. previously isolated from apple, together with reference isolates of A. alternata and A. infectoria, were characterised and grouped according to their sporulation patterns and conidial morphology. Isolates were identified as belonging to A. arborescens, A. infectoria and A. tenuissima species-groups. The isolates were also analysed for production of mycotoxins and other secondary metabolites and their cultural characteristics on DRYES medium were recorded. Apple fruit were artificially inoculated with the thirty-two Alternaria isolates and the resulting lesion types were recorded. A data matrix was constructed using all these characters and subjected to cluster analysis to show the similarity between different isolates. Isolates classified as A. infectoria species-group based on sporulation patterns, cultural and biochemical data could be easily differentiated from isolates classified as A. arborescens and A. tenuissima species-groups, which clustered close together. Isolates were further subjected to DNA sequence analysis of the internal transcribed spacers (ITS) 1 and 2 of the nuclear rRNA gene. A phylogeny estimated from the ITS data set delineated two clades, one being typified by the A. infectoria species-group, and the other representing both A. tenuissima and A. arborescens species-groups. The ITS data set clearly separated isolates of A. infectoria species-group from the other species-groups, as all isolates had a distinction of 35 base pair insertions and 6 base pair deletions in the ITS regions. The results obtained in the present study showed that the major pathogens associated with core rot disease of Top Red apples in South Africa belong to the A. tenuissima species-group.
dc.description.versionArticle
dc.identifier.citationMycological Research
dc.identifier.citation106
dc.identifier.citation5
dc.identifier.issn9537562
dc.identifier.other10.1017/S0953756202005993
dc.identifier.urihttp://hdl.handle.net/10019.1/10386
dc.subjectmycotoxin
dc.subjectnuclear RNA
dc.subjectribosome RNA
dc.subjectfruit
dc.subjectfungal disease
dc.subjectstorage
dc.subjectapple
dc.subjectbase pairing
dc.subjectcluster analysis
dc.subjectcore rot disease
dc.subjectcultivar
dc.subjectculture medium
dc.subjectDNA sequence
dc.subjectfungal plant disease
dc.subjectinoculation
dc.subjectmetabolite
dc.subjectphylogeny
dc.subjectpostharvest period
dc.subjectSouth Africa
dc.subjectspecies
dc.subjectsporogenesis
dc.subjectSouth Africa
dc.subjectAlternaria
dc.subjectAlternaria alternata
dc.subjectAlternaria arborescens
dc.subjectAlternaria infectoria
dc.subjectAlternaria tenuissima
dc.titleCharacterisation of Alternaria species-groups associated with core rot of apples in South Africa
dc.typeArticle
Files
Collections
Stellenbosch University - Scopus Publications