Survival ofColletotrichum graminicola:Importance of the Spore Matrix

Publisher Website
Google Scholar
Abstract
Spores of C. graminicola [anthracnose pathogen of Zea mays] are produced in association with a water-soluble matrix material composed of polysaccharide(s) and protein. Spore masses (spores embedded in spore matrix) placed at relative humidities of 90, 80, 70, 60 and 45% lost moisture rapidly and at low relative humidities (70% or less) became dry and powdery within 48 h. Spores in masses stored at these relative humidities retained viability (measured by germination bioassay) throughout 4 wk. When the spore matrix was removed prior to storage, viability of the population was significantly reduced within 24 h (at each relative humidity treatment) and viability was completely lost within 48 h. Addition of concentrated crude matrix or partially purified matrix components to washed (matrix-free) spores prior to storage at low relative humidity maintained viability of the spore population. In the field, spores may survive and be dispersed in dry particulate matter. Hydrolase and invertase enzymes are present in the matrix. Desiccation of the matrix at low relative humidity did not result in a complete loss of enzyme activity. Two roles for the spore matrix in survival of the pathogen are suggested: protection of spores against desiccation and increase in efficiency of germination and penetration through invertase and hydrolase activities.

This publication has 1 reference indexed in Scilit: