Electrophoretic studies of soluble proteins and enzymes of sclerotinia species

Abstract

An electrophoretic study of the proteins and isoenzymes of isolates of Sclerotinia sclerotiorum (Lib.) de Bary, S. trifoliorum Erikss. and S. minor Jagger was made to obtain further information on the taxonomie relationships of these fungi. Electrophoretic patterns for soluble proteins, aromatic esterase, acid phosphatase, glucose-6-phosphate dehydrogenase (NADP), NADPH dehydrogenase and malate dehydrogenase (NAD) clearly distinguished three groups: (i) isolates producing small sclerotia which at the start of the investigation were regarded as S. minor ; (ii) isolates from forage legumes (lucerne) which form large sclerotia ; (iii) isolates which had been designated S. sclerotiorum and two isolates from crop legumes initially named S. trifoliorum on Sclerotium size. There were only very small intra-group differences. The isolates in the second group appeared to be intermediate between those in the other two groups. It is tentatively suggested that the name S. trifoliorum should be used for isolates from forage legumes, while those from vegetable legumes should be regarded as S. sclerotiorum . Isolates producing small sclerotia are distinct from both these species and may be called S. minor .