Lovrekovich, L., Research Institute for Plant Protection, Budapest
Farkas, G.L., Research Institute for Plant Protection, Budapest
THE wildfire disease of tobacco, caused by Pseudomonas tabaci (Wolf and Foster) Stevens, is characterized by the development of chlorotic halos around the infection sites. This symptom is induced by a bacterial toxin. The toxic compound proved to be a structural analogue of methionine1. Strangely enough, its effect could be overcome by methionine only in model experiments with Chlorella vulgaris2. The mode of action of the wildfire toxin in tobacco leaves, therefore, remained obscure. © 1963 Nature Publishing Group.