Studies on bacterial soft rot of celery in Victoria

The causal organism of bacterial soft rot of celery was isolated and characterized, and its control was studied. The causal organism was identified as Erwinia carotovora var. carotovora (Jones) Dye. It was also pathogenic on potato in the glasshouse, causing atypical black leg symptoms. The practical implications of this finding are discussed. Infection appeared to occur at all temperatures tested in the range 1-35°C. Disease development was optimal at 30°C, but was completely checked at 1°C. Four chemicals were evaluated in the laboratory for control in transit and storage. Sodium hypochlorite provided the best control. Two copper fungicides were evaluated in the field. Cupric hydroxide provided the best control. The suitability of using this fungicide for the control of Septoria leaf spot as wall, during summer, is discussed.