DETECTION OF HELMINTHOSPORIUM-SOLANI FROM SOIL AND PLANT-TISSUE WITH SPECIES-SPECIFIC PCR PRIMERS

Two PCR primer pairs specific for Helminthosporium solani, which cause s silver scurf on potato tubers, were designed from nucleotide sequenc es of the nuclear ribosomal internal transcribed spacer regions of II. solani. Both primer pairs amplified a single product with DNA from 48 North American and European isolates of H. solani, but not with DNA f rom 42 other fungi. Primers also amplified a single product with DNA e xtracted from silver scurf lesions on potato tubers and other plant ti ssue inoculated with spores of H. solani. Detection of the fungus in i nfested soil was only possible with nested PCR and after processing so il with a bead beater. Specific amplification of H. solani DNA can be used to study the saprophytic and pathogenic activity of this fungus i n soil and plant tissue. (C) 1998 Federation of European Microbiologic al Societies. Published by Elsevier Science B.V. All rights reserved.