Journal of Plant Pathology Archive

Abstract:

In early February 2011 severe blight and stem necrosis symptoms on eggplants of cv. 1017 grafted onto rootstock AGR-01 F1 were observed in commercial greenhouses in Fethiye (Mug?la province, Aegean Turkey). Disease incidence was estimated to approach 10-12% in some greenhouses with poor air circulation and very high relative humidity. Symptoms started with watersoaking followed by blackening of large areas of the upper stem. Blighting progressed towards the petiole and midrib of the leaves, which later collapsed followed by dieback of the whole foliage. On some plants irregular brown to black stem lesions of different size developed which evolved in brown discoloration and necrosis of the pith. Fluorescent, Gram-negative, aerobic bacteria were consistently isolated from all damaged plant organs. Based on morphological, biochemical and pathogenicity tests, the bacterial strains isolated from infected leaf midribs, petioles, blighting stem and large stem lesions were identified as Pseudomonas cichorii and the strains isolated from necrotic pith and small stem lesions as P. viridiflava. This is the first report of bacterial blight and pith necrosis disease on eggplant differing from necrotic leaf spot or bacterial leaf blight and the first evidence for the presence of P. cichorii and P. viridiflava on this host plant in Turkey.