Pseudomonas syringae pv. tagetis, Causal Agent of Apical Chlorosis, Isolated from Sunflower in Kansas. D. L. Seifers, Fort Hays Branch, Agricultural Experiment Station, Hays, KS 67601. W. D. Stegmeier, Fort Hays Branch, Agricultural Experiment Station, Hays, KS 67601. Plant Dis. 67:1290. Accepted for publication 26 August 1983. Copyright 1983 American Phytopathological Society. DOI: 10.1094/PD-67-1290.

Apical chlorosis of sunflower (Helianthus annuus L.) was observed in Kansas in 1982. Isolations from symptomatic tissue consistently yielded gram-negative fluorescent bacteria that caused symptoms characteristic of apical chlorosis when inoculated into greenhouse-grown sunflower plants. Bacteria reisolated from chlorotic tissue were further characterized and compared with isolates of Pseudomonas syringae pv. tagetis (Hellmers 1955) Young, Dye & Wilkie 1978 from North Dakota. The isolates reacted similarly to physiological characterization tests (oxidase and arginine dihydrolase reactions, induction of hypersensitive reaction in tobacco, use of carbon sources, potato soft rot, growth at 41 C, and levan formation). This is the first report of P. tagetis occurring in Kansas.