OLEANDER KNOT CAUSED BY PSEUDOMONAS SAVASTANOI pv NERII IN TURKEY
H. Kavak, N. Üstün
A knot disease was detected on some oleander plants in two park since 2007 and in one home gardens in 2008 in the Sanliurfa province (south-east Turkey). Although galls were excised in the first year, they developed again with a bigger size on the lower parts of the main stems. Knots on newly infected plants were common on the upper parts, particularly on twigs, flowers and pistils or at the pistil base. Almost all infected plants belonged to cultivars with pink or red flowers. Biochemical and pathogenicity tests identified the plant pathogenic bacterium Pseudomonas savastanoi pv. nerii as the causal agent of the disease. Although the presence of knots on oleander has long been known, to our knowledge, Pseudomonas savastanoi pv. nerii had never been previously reported on Nerium oleander in Turkey.