Assessing the Genetic Diversity of <i>Alternaria Bataticola</i> in South Africa using Molecular Markers


  • J. Chalwe Department of Biotechnology, Vaal University of Technology Private Bag X021, Vanderbijlpark
  • P. Adebola Department of Biotechnology, Vaal University of Technology Private Bag X021, Vanderbijlpark
  • M. Pillay Africa Rice Center (AfricaRice), Abidjan, Cote d’Ivoire



Alternaria bataticola, sweetpotato, genetic diversity, RAPD, ITS2, secondary structure prediction


Sweetpotato (Ipomoea batatas) an economically important food crop is affected by viral and fungal diseases. The most important fungal disease is Alternaria blight caused by Alternaria bataticola. Alternaria blight can be controlled using fungicides and cultural practices in the short-term. A sustainable control measure is the development of resistant sweetpotato cultivars. A prerequisite to this approach is the knowledge of the genetic diversity of this fungal pathogen. This study assessed the genetic diversity of A. bataticola in South Africa using RAPD analysis, DNA sequencing and secondary structures of the ITS2 region. Samples were collected from 25 different localities and the pathogen was identified in the laboratory. Both RAPD and ITS2 sequence data showed that there is high levels of genetic diversity among the isolates of A. bataticola. Although the dendrograms generated from the RAPD and ITS2 sequences clustered some isolates according to their place of origin, the majority of isolates did not group according to their geographic origins. The predicted ITS2 secondary structure models were variable ranging from simple to complex. The unique secondary structures of each isolate can be used to identify and distinguish each of the isolates used in this study. 



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How to Cite

Chalwe, J., Adebola, P., & Pillay, M. (2017). Assessing the Genetic Diversity of <i>Alternaria Bataticola</i> in South Africa using Molecular Markers. Asian Journal of Applied Sciences, 5(2).