Occurrence of Benomyl-Resistant Isolates of Glomerella cingulata (Stoneman) Spaulding et Schrenk in Tea Fields

Abstract

To evaluate the resistance to benomyl of isolates of tea brown blight fungus, Glomerella cingulata, leaves and shoots infected with the fungus were collected from tea plants cultivated in three prefectures in Japan. The isolates were tested on PSA media containing fifteen concentration levels of benomyl (0.05 μg/ml-800 μg/ml). They were classified into three groups based on minimum inhibitory concentration values, i. e., resistant, intermediately resistant and susceptible isolates, whose MIC were 0.2, 12.5 and 800 μg/ml or more, respectively.