Glucose phosphate isomerase polymorphisms distinguish weakly virulent from highly virulent strains ofLeptosphaeria maculans

Relationships among measures of blackleg in winter oilseed rape and infection of harvested seed byLeptosphaeria maculans

“…More detailed studies are required to determine whether the two pathotypes selectively colonize different tissues. As previously reported, high virulence was associated with the fast isozyme of glucose phosphate isomerase (Sippell & Hall 1995), and slow mycelial growth and lack of pigment production in culture (Williams 1992). The study shows that the highly virulent pathotype of L. maculans commonly infects harvested seed of winter oilseed rape in the major production area in Ontario.…”

“…The occurrence of the fast or slow isozymes of glucose phosphate isomerase in isolates from seed was determined by starch gel electrophoresis as described by Sippell and Hall (1995).…”

Electrophoretic analysis of natural populations of Leptosphaeria maculans directly from leaf lesions

“…The isolation also permitted the study of pigment production, described as a useful marker by Johnson & Lewis (1994) for distinction between A-and B-groups. Nevertheless, as previously reported by Sippel & Hall (1995), pigment production overlapped the two groups, since one A-group isolate produced a pinkish pigment.…”

“…21) and ET2 (Rf 1 . 12) were characteristic of the A-group (isolate 940) and Bgroup (isolate 945) respectively; the nomenclature of allozymes follows that proposed by Sippel & Hall (1995). Comparisons with these controls enabled most of L. maculans leaf lesions to be assigned unequivocally to one of these two electrophoretic types.…”

“…Isozyme analysis has been used successfully in the identification of several plant pathogenic fungi (Bonde et al, 1993). With axenic cultures of A-and B-group isolates of L. maculans, Sippel et al (1988), Hall et al (1993) and Sippel & Hall (1995) distinguished unequivocally the two L. maculans groups by glucose phosphate isomerase (GPI) patterns. All A-group isolates were characterized by one electrophoretic type (ET1), and all B-group isolates by another (ET2).…”