The susceptibility of tissue cell walls to Erwinia enzymes differs among the potato cultivars

In the cell wall matrix of higher plants, cellulose fibrils are embedded in a network of pectic substances, hemicelluloses and structural proteins. But plant pathogenic Erwinia carotovora bacteria secrete a mixture of enzymes including pectinases, cellulases and proteases to degrade the cell walls of host plant tissue. Tuber tissue of 31 potato genotypes was exposed to a mixture of Erwinia enzymes before the degree of cell wail lysis was determined by a Neutral-red vital staining method. The data indicate that the resistance of cell walls to the action of Erwinia enzymes differed significantly among the potato cultivars and clones. The decrease in cell viability caused by the action of enzymes ranged from 7% for cv. Maxilla to >46% for cv. Arnika. An increased rate of N-fertilization coincided with enhanced susceptibility of cell walls to the action of Erwinia enzymes. There was a correlation between the amount of cell wall substances in tuber tissue and the resistance of cell walls to enzymic degradation.