Eremothecium ashbyi causes soybean yeast-spot and is associated with stink bug, Riptortus clavatus

Many fusiform ascospores observed on soybean seeds with yeast spot disease symptoms differed significantly from those of Eremothecium coryli , the known causal agent of yeast spot disease in soybean. On the basis of morphological and physiological characteristics and sequence data of the internal transcribed spacer regions including the 5.8S rDNA and D1/D2 regions of 26S rDNA, this fungus was identified as E. ashbyi . Pathogenicity of E. ashbyi was confirmed by reinoculation test. This report is the report on E. ashbyi causing soybean yeast spot disease. In addition, this study showed that E. ashbyi was transmitted by the stink bug, Riptortus clavatus , as was E. coryli , the two Eremothecium yeasts may have been acquired when the stink bug fed on infected soybeans and overwintered in this insect species.