Resistance of red and white clover cultivars to clover rot (Sclerotinla trifoliorum)

Various techniques for assessing the resistance of clover cultivars to clover rot have been investigated, including counting sclerotia around infected plants, measuring lengths of healthy and diseased rows and the use of a key to assess symptom expression on individual plants. The latter was found to be the most suitable under field conditions. Of fifty-one red clover cultivars tested, nineteen were found to possess some level of resistance. Clover rot appears to be an increasing problem with white clover crops but tests have indicated that resistant cultivars are available.