• The Plant Pathology Journal
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• v.18 no.6
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• pp.338-341
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• 2002

The potato scab is caused by several species of Streptomyces. Among these species, only pathogenic strains were found to produce thaxtomin A characterized by necrotic bioassay and HPLC. In this study, identification of the pathogenic strains of Streptomyces was performed through the polymerase chain reaction (PCR) by using specific pathogenicity primer sets derived from the nec1 gene sequences of Streptomyces scabies. The expected PCR products were obtained approximately 580 bp and confirmed by sequencing. This PCR technique can be used effectively to identify the pathogenic Streptomyces species, that cause scab on potato tubers.

• Proceedings of the Microbiological Society of Korea Conference
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• 2005.05a
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• pp.162-165
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• 2005

Potato scab, an important disease that affects developing tubers, causes a major problem in potato cultivation. The major potato cultivation areas in Korea are located in two Northern provinces, Gangwon and Gyeonggi, and two Southern provinces, Jeju island, and South Jeolla. In these areas, potato scab is widely distributed and has caused severe problem in potato cultivation. Therefore, potato-growing areas were surveyed for identification and distribution of potato scab pathogens from 1996 to 1999. Pathogenic Streptomyces strains were isolated from potato scab lesions and six representative Streptomyces species were characterized based on their phenotypic and molecular characteristics including, pathogenicity, physiological and morphological properties, analyses of 16SrRNA genes and 16S-23S ITS region, DNA relatedness, production of thaxtomin A, and the presence of nec1 and ORFtnp gene homologs. Three species were identified as previously described Streptomyces scabies, S. turgidiscabies, and S. acidiscabies, while other three species having distinct phenotypics properties were identified as novel S. luridiscabiei, S. puniciscabiei, and S. niveiscabiei.