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Disease Note.

First Report of Leveillula taurica in Hawaii. J. Y. Uchida, Department of Plant Pathology University of Hawaii, Honolulu 96822. D. Y. Ogata, Agricultural Diagnostic Service Center, University of Hawaii, Honolulu 96822. Plant Dis. 79:966 . Accepted for publication 24 July 1995. Copyright 1995 The American Phytopathological Society. DOI: 10.1094/PD-79-0966D.

In April 1995, bell pepper (Capsicum annuum L), severely infected with Leveillula taurica (Lev.) G. Arnaud, was observed on about 8 hectares of mature plants on the island of Oahu. Light chlorosis in mottled patterns appeared on lower leaves of nearly all of the plants and the abaxial leaf surface was covered by the fungus.\Necrotic older lesions, defoliation, and sun scalding of exposed fruits followed a week later. The pathogen was identified by the following: endophytic mycelium branched conidiophores navicular, obpyriform to ovoid terminal conidia cylindrical, sub-terminal conidia and conidia borne singly or in short chains of mostly two conidia. Mean conidial dimensions were 65.0 plus or minus 5.4 ? 17.2 plus or minus 2.1 μm for obpyriform types and 63.7 plus or minus 5.3 ? 16.2 plus or minus 2.3 μm for cylindrical types. Fifty spores were measured for each type. Although slightly larger than the means given for most California isolates (1), these measurements are comparable. Cleistothecia were not observed. Leveillula taurica was also discovered on ornamental spiderflower (Cleome spinosa Jacq), artichoke (Cynara scolymus L), and chili pepper (Capsicum annuum [Longum Group]) in nearby fields. The origin of L. taurica, the significance of disease development in relatively cool areas of the state, and epidemic potential in the tropics are unknown.

Reference: (1) J. C. Correll et al. Plant Dis. 71:248, 1987.