Sodium bicarbonate enhances biocontrol efficacy of yeasts on fungal spoilage of pears

The addition of 2% (w/v) sodium bicarbonate (SBC) in the suspensions of antagonistic yeast Cryptococcus laurentii or Trichosporon pullulans significantly limited spore germination and germ tube elongation of Penicillium expansum and Alternaria alternata in potato dextrose broth (PDB) medium. Biocontrol activity of C. laurentii or T. pullulans against postharvest decay caused by P. expansum and A. alternata in pear fruits was significantly increased when C. laurentii or T. pullulans combined with SBC. Combining C. laurentii or T. pullulans with SBC provided a more effective control on P. expansum and A. alternata than applying the antagonistic yeast or SBC alone. Effects of C. laurentii with and without SBC on controlling P. expansum and A. alternata were better than those of T. pullulans. C. laurentii in combination with SBC showed the best control of disease caused by A. alternata in pear fruits.