Symptoms on bean and lettuce were similar to those described for P. Symptoms on basil plants inoculated by injection or spraying with Carborundum were identical to those observed on basil in the field. After 48 h in a humid chamber, inoculated plants and controls were maintained at 23 ± 3☌. criolla), both reported as host plants, were inoculated by spraying with bacterial suspensions of 10 7 cells per ml plus Carborundum. Nag12 INTA) and lettuce (Lactuca sativa cv. In addition, bean (Phaseolus vulgaris cv. Controls were injected or sprayed (with and without Carborundum) with sterile, distilled water. Carborundum was included in the inoculum used for a set of plants inoculated by spraying. Pathogenicity was verified on 35-day-old basil plants by both spraying and infiltration inoculations with bacterial suspensions (10 8 and 10 5 cells per ml, respectively). Reactions were identical to those of reference strains ICMP 573, which were included in all tests for comparison. Isolates hydrolyzed gelatine, used Tween 80, were positive for catalase, and were unable to grow in the presence of 5% NaCl. Negative reactions were obtained with indole, ornithine, and D-tryptophan. The strains did not hydrolyze starch, exhibited an oxidative metabolism of glucose, and did not reduce nitrates to nitrites or accumulate poly-β-hydroxybutyrate inclusions. Bacteria used D-tartrate, pyruvate, and citrate, but not benzoate. Acid was produced aerobically from D-glucose, mannitol, mesoinositol and sorbitol, but not from D-arabinose, L-rhamnose, melibiose, amygdalin, or sucrose. In addition, strains rotted onion slices and produced a reddish sunken lesion on bean pods. In LOPAT (levan-oxidase-potato rot-arginine dihydrolase-tobacco hypersensitivity) tests, all induced a hypersensitive response in tobacco plants, caused soft rot of potato tubers, and were negative for levan, oxidase, and arginine dihydrolase. Four isolates selected for further study were aerobic, Gram-negative, non-spore-forming rods. Bacterial growth produced a distinctive olive green pigment on glycerol agar medium and a pink pigment on T-5 medium (1). Bacteria consistently isolated from leaf lesions formed cream-colored, glistening, convex colonies on sucrose peptone agar and a green fluorescent pigment on King's medium B. Bacterial streaming was observed from lesion margins. No pathogenic fungi or viruses were associated with symptomatic plants. (2) on basil affected by Pseudomonas viridiflava. Symptoms were similar to those reported by Little et al. Spots on leaves were first water soaked, then became necrotic and progressed inward from the margins. Affected plants had dark brown to black lesions on cotyledons. 'Royal Louis' and 'Zaes') in a commercial greenhouse in La Plata, Argentina. In June 1998, during a cool, humid period, typical bacterial spot symptoms were observed on basil plantlets (Ocimun basilicum L.
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