Effect of two strains of antagonistic yeasts in combination with silicon against two isolates of Penicillium expansum on apple fruit

ABSTRACT: The potential of two antagonistic yeasts Candida membranifaciens (A4) and Pichia guilliermondii (A6) lonely and in combination with different concentration of Silicon (Si) 0.1%, 0.3% and 0.5% w/v were investigated for control of two isolates of Penicillium expansum P1 and P2 on apple fruit in storage at 5°C. The results indicated that the antagonistic yeasts could control the blue mold caused by both isolates, significantly. Complete control of disease achieved using combination of A6 with Si at 0.1% for P1 and at all concentrations for P2 (P < 0.05). While combination of A4 with Si at 0.5% could control the blue mold caused by P1, significantly. Si decreased the growth of the both yeasts A4 and A6 In vitro. Also, Si inhibited the growth of the both isolates P1 and P2 at concentrations above 0.6% w/v. The results of this study emphasized the synergistic effects of the yeasts A4 and A6 in combination with Si and the different behaviors of P. expansum isolates against the combined treatments.