Morphological and pathogenic characteristics of Colletotrichum trifolii Bain et Essary, the alfalfa anthracnose inducer

Abstract

During summer and autumn, easily recognizable diseased plants can be detected in alfalfa fields. Diseased plants have characteristically curved apical part, commonly known as 'shepard's hook'. Using the standard mycological methods, several fungi isolates were obtained. Four of these isolates were used for further study. Two standard mycological methods were used for determination of pathogenicity of Colletotrichum spp. isolates: with and without damaging of the stems. During these studies, it was determined that all of the isolates were causing the symptoms of alfalfa anthracnose. All of the selected isolates form germinative bodies - acervulae - on mycelium. Acervulae can be grouped or scattered across the colony area. Their size in the culture was 100-250 mm. Conidia were short, cylindrical, relatively broad, with both end obtuse 7,85 x 3,85 mm. Appressoria were ovate to obovoid, pale to medium brown 7,5-16,5 x 5,5-8,9 μm.

Keywords

• Colletotrichum trifolii Bain et Essary
• alfalfa
• morphology
• pathogenicity