First Report of Bacterial Leaf Spot of Castor Bean in Yugoslavia. M. Arsenijevi?, Faculty of Agriculture, 21000 Novi Sad, Yugoslavia. S. Masirevi?, and M. Goto. Faculty of Agriculture, 21000 Novi Sad, Yugoslavia, and Faculty of Agriculture, Shizuoka University, 836 Ohya, Shizuoka 422, Japan. Plant Dis. 76:1283. Accepted for publication 17 January 1992. Copyright 1992 The American Phytopathological Society. DOI: 10.1094/PD-76-1283E.
In 1990, a bacterial leaf spot of castor bean (Ricinus communis
L.) was observed for the first time in a breeding field at the Research
Institute of Field and Vegetable Crops, Novi Sad, Yugoslavia. The
spots varied in size, were surrounded by halos, and became necrotic.
More than 20 strains of the pathogen were isolated from lesions on
diseased leaves. The nonsporulating, gram-negative, rod-shaped
bacterium formed white colonies and produced fluorescent pigment
on King's medium B. Infiltration of bacterial suspensions into
pelargonium leaves and bean pods produced typical hypersensitive
reactions. Reactions in LOPAT tests were +, -, -, -, and +,
respectively. On the basis of these results and the formation of halos
around necrotic lesions on inoculated castor bean leaves, we concluded
the causal agent was a pathovar of Pseudomonas syringae van Hall.
P. s. ricini was first described in Romania (1) in 1986 and is the
likely incitant of bacterial leaf spot of castor bean in Yugoslavia.