Bacterial Blight of Suger Beet Caused by Pseudomonas aptata (Brown et Jamieson) Stevens

Publisher Website
Google Scholar
Abstract
In December, 1965, in the warm South-Western part of Japan, an explosive outbreak of unknown plant disease was observed on the fall sown suger beet field, causing a considerable damage. Again in June, 1966, in the cold North-Eastern part, a plant disease suddenly broke out on the spring sown suger beet field, just after the passage of a typhoon. Its symptoms were a little different from those of the former. In the former case, remarkable streaks were seen on the midlib and petiole, though few ring spots appeared on the leaf-blade. Moreover, the vascular bundles of the root turned black and the crown of the plant, suffering a great damage, was rotten during winter. In the latter, many ring spots could be seen on the leaf-blade. Some cases of streaks on the midlib and petiole and blackend vascular bundles were observed, but no decay of the crown. It has been found out that both the diseases were caused by the same pathogen, though there were some differences between them in the time of outbreak, the symptoms on the plant, the rottenness of the crown, etc. Bacteriological characters of the causal organism resemble those of Pseudomonas aptata or Ps. coronafaciens. Considering, however, the fact that it is pathogenic to beet, nasturtium, and green pepper but not to oats, the auththor cannot but conclude that the pathogen was Ps. aptata (Brown et Jamieson) Stevens. One of the reasons of the occurrence of the disease, he supposes, was that the beet varieties E-4 (Donyu-2), E-5 (Tsukisappu) etc. are susceptible to the organism. The outbreak of this disease had never been seen in Japan before. The bacteriological characters of the pathogen are as follows. It is an aerobic, Gram-negative rod, occurring singly, in pairs, with 1 to 2 mono- or bipolar flagella. A green fluorescence is produced in King's agar. On agar the colonies are dirty white, round, convex, smooth, moist, glistning and butyrous. It grows feebly in Uschinsky's solutions, but not in Cohn's. Gelatin is liquefied, but nitrate is not reduced. Milk is neither coagulated nor peptonized, and litmus is reduced. Ammonia is formed but indole and hydrogen sulphide are not produced. Acid but no gas is formed from arabinose, rhamnose, xylose, glucose, fructose, galactose, mannose, sucrose, raffinose, mannitol and sorbitol and, by certain strains, from glycerol also in Ayers, Johnson agar with BTB as indicator; neither acid nor gas from lactose, maltose, starch, inulin, or dextrin or, by certain strains, from glycerol also. Starch is not hydrolysed. It tolerates the addition of 5% sodium chloride solution. The thermal death-point is at 49°C.

This publication has 0 references indexed in Scilit: