Geographical distribution, diversity and pathogenicity of Colletotrichum associ-ated with soybean anthracnose in Brazil

Abstract

Eighty-five Colletotrichum isolates were obtained from soybean croplands in 34 municipalities of Mato Grosso state. Our objectives were characterize the isolates through mycelial growth, cultural and morphological analyses, as well as assessing pathogenicity. To evaluate cultural characteristics, the mycelial growth was daily measured, and the color of colonies was characterized after ten days incubation. The morphology, length, and width of 50 conidia per isolate were assessed. The pathogenicity of twenty-one isolates was evaluated on seed germination rate, incidence, and detection of extracellular enzymes. The cultural and morphology characteristics of Colletotrichum isolates were greatly variable. All isolates studied were able to reduce seed germination, produce sign and proteinase activity. These results suggest there are more than one Colletotrichum species associated with soybean anthracnose in Mato Grosso State.

Keywords

• morphological and cultural traits
• glycine max