Abstract
A total of 13 isolates of Phialophora gregata from adzuki bean and soybean were examined for pathogenicity to adzuki beans, soybeans, mung beans, kidney bean, cowpea and pea by two inoculation tests. Isolates from adzuki bean were pathogenic to adzuki beans and mung beans, while isolates from soybean were pathogenic to soybeans and mung beans. That is, the isolates formed two distinct groups based on their pathogenicity to adzuki bean and soybean. The isozyme polymorphisms and DNA sequence homology, with its complete correspondence with pathogenicity, support the grouping of P. gregata isolates into two formae speciales. Accordingly, we proposed two formae speciales for this fungus on the basis of the specific pathogenicity P. gregata f. sp. adzukicola for adzuki bean pathogen and P. gregata f. sp. sojae for soybean pathogen.
