Recent renewed cultural and physiological studies on the fruit collapse and heart rot organism showed it to be Erwinia chrysanthemi Burkholder and not Erwinia chrysanthemi (J.ones) Holland as hitherto believed. Salient differences are their reactions to the methyl red test. acetylmethylcarbinol production, growth in 5 percent sodium chloride, utilisation of sodium citrate. acid production from lactose. maltose and trehalose and their colony appearance on Endo agar. Pathogenicity studies showed E. chrysanthemi to be pathogenic on pineappie leaves and fruits while E. carotovora was not. Furthermore. E. carotovora could cause extensive soft rot symptoms on cabbage leaves while E. chrysanthemi could only inflict limited lesions.

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