LEAKAGE OF ELECTROLYTES AND PHENOLS FROM APPLE LEAVES CAUSED BY VIRULENT AND AVIRULENT STRAINS OF ERWINIA-AMYLOVORA

Apple leaves infiltrated with virulent and avirulent strains of E. amylovora showed a linear relationship of leakage of electrolytes and total phenols during the first 5 h. Thereafter, the rate of increase of electrolyte and phenol concentrations was nonlinear. With the avirulent strain leakage of phenol was 1 h earlier than the leakage of electrolytes. With the virulent strain leakage of phenols and electrolytes occurred simultaneously. Both phenomena occurred sooner in tissues infiltrated with the avirulent strain. Both occurred well in advance of visible browning symptoms which were evident about 12 h after infiltration.