STUDIES IN THE BACTERIAL DISEASES OF SUDAN CROPS

The bacterial leaf spot disease of jute ( Corchorus olitorius ) is characterized by the development of brown circular spots, about 2–5 mm. in diameter, on the leaves, surrounded, sometimes, by a yellow halo. The disease on the stems causes elongated lesions, and on the capsules produces small sunken spots. Defoliation and death of the stems may result in severe infections. The disease is ascribed to a new variety of Xanthomonas nakatae (Okabe) Dowson, the cause of a somewhat similar disease of Corchorus capsularis in Formosa (Elliott, 1951), on the ground that: (i) the minor differences between the two pathogens in biochemical characters are considered well within strain differences, and (ii) the Sudan pathogen does not infect C. capsularis , and Xanthomonas nakatae has not been reported to infect Corchorus olitorius . These differences do not justify the creation of a new species. The name Xanthomonas nakatae v. olitorii is suggested for the cause of the disease under consideration.