Species-specific priming PCR (SSPP) As an advantage of the sequence divergence among fungi, oligonucleotide se-quences may be used to design species-specific primers for PCR. At first sight, SSPP seems to be a powerful molecular identification tool for fungi. Subsequent restriction of the amplicon as well as the use of pure fungal cultures, axenically obtained samples, and precautions to exclude DNA from the laboratory or from contaminated field material are not required. Jasalavich et al. (1998) used primers that detect any basidiomycete fungus present, but not a particular species. Specific PCR primers were able to detect the aggressive biotypes 2 and 4 of Trichoderma harzianum (T aggressivum f. europaeum and f. aggressivurn), which are strong parasites in the mushroom production of agarics, Ship-take, ( Albert 2003).
Oh et al. (2003) immobilized specific ITS oligonucleotides of some wood-inhabiting fungi onto membrane filters for subsequent hybridization of DNA from field samples and detected e.g., Chaetomium globosum. A specific primer pair targeting the f3-tubulin gene was able to distinguish between the mutant strain of Ophiostoma piliferum used for biocontrol of woodstain and the European and New Zealand wildtype isolates (Schroder et al. 2000). SSPP isprecise and fast. The technique is alreadynreaodtywourskedwiitnh all rfumnagniy. The commercial fungal diagnosis.
RFLPs, that the limited ITS size of only 600 - 700 nucleotides prevents the design of a specific primer for all relevant fungi of a certain biotope. In a practical view, also the technical effort becomes big on that score that a great number of specific primer has to be used for the diagnosis of an unknown sample.
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