Published on Tuesday, 21 October 2014 14:12
Written by Karl Danneberger
With the high summertime temperatures turfgrass plants become susceptible to diseases not normally considered a problem. Curvularia species (ex. C. lunata, C. trifolii, C. eragrostidis
) are normally weak pathogens but can become severe on turfgrass plants weakened from heat and/or moisture stress. Curvularia disease symptoms are most evident on senescing plant tissue primarily leaves. On senescing tissue conidia from the pathogen infect and sporulate profusely. Symptoms initially appear as indistinct yellow and green mosaic type of pattern extending from the leave tip down (the oldest part of the leaf is the tip). The leaves eventually shrivel and turn a grayish color; except with creeping bentgrass where the leaves appear tan. If warm wet weather occurs rapid infection of plant tissue can occur.
Photograph 1: Curvularia symptoms on a perennial ryegrass athletic field
Curvularia is a difficult disease to control because the turf plants are under severe environmental stress. Practices like minimizing soil compaction, providing a better growing environmental condition, and proper cultural management (balanced fertility, proper watering, etc.) can help make for a healthier turfgrass plant. In some instance fungicides may be warranted.
Photograph 2: Curvularia symptoms on a “Tifeagle” bermudagrass green.