Mating Type Locus-Specific Polymerase Chain Reaction Markers for Differentiation of Pyrenophora teres f. teres and P. teres f. maculata, the Causal Agents of Barley Net Blotch

Abstract

Lu S Platz G J Edwards M C and Friesen T L 2010 Mating type locus specific polymerase chain reaction markers for differentiation of Pyrenophora teres f teres and P teres f maculata the causal agents of barley net blotch Phytopathology 100 1298-1306 Fourteen single nucleotide polymorphisms (SNPs) were identified at the mating type (MAT) loci of Pyrenophora teres f teres (Ptt) which causes net form (NF) net blotch and P tens f maculata (Ptm) which causes spot form (SF) net blotch of barley MAT specific SNP primers were developed for polymerase chain reaction (PCR) and the two forms were differentiated by distinct PCR products PttMATI 1 (1 143 bp) and PttMATI 2 (1 421 bp) for NF MAT1 1 and MATI 2 isolates PanMATI (194 bp) and PtmMAT1 2 (939 bp) for SF MAT1 1 and MAT1 2 isolates respectively Specificity was validated using 37 NF and 17 SF isolates collected from different geographic regions Both MAT1 and MAT1 2 SNP primers retained respective specificity when used in duplex PCR No cross reactions were observed with DNA from P graminea P trawl repent is or other ascomycetes or barley Single or mixed infections of the two different forms were also differentiated This study provides the first evidence that the limited SNPs at the MAT locus are sufficient for distinguishing closely related heterothallic ascomycetes at subspecies levels thus allowing pathogenicity and mating type characteristics of the fungus to be determined simultaneously Methods presented will facilitate pathogen detection disease management and epidemiological studies