Biological control of Penicillium italicum of citrus and Botrytis cinerea of grape by Strain 34-9 of Kloeckera apiculata

The biological control capability of strain 34-9 of Kloeckera apiculata against Penicillium italium (Wehmer), postharvest rot of citrus fruits and Botrytis cinerea, postharvest rot of grape fruits was studied in vitro and in vivo. Strain 34-9 of K. apiculata at 3 x 10(8) CFU (colony-forming unit)/ml of washed cells provided complete control of 3 x 10(5) spores/ml of P. italium and B. cinerea during storage at 25 degrees C for 6 d. Antagonist population increased 40, 195 times in citrus fruit wound site and grape fruit wound site at 25 degrees C for 3 d, respectively, then the population stabilized for the remaining storage period. Cell-free culture filtrate, supernatant fluid and sterilized solution of strain 34-9 of K. apiculata had no antagonist against P. italium of citrus and B. cinerea of grape. These results showed that competition for nutrient, not antibiotic production, played a major role in the biological control capability of strain 34-9 of K. apiculata against P. italium of citrus and B. cinerea of grape.