Abstract:

The biocontrol effects of Bacillus licheniformis W10 bacterial suspension and its antifungal protein on peach brown rot caused by Monilinia fructicola in storage peach fruits and the effects on fruit quality were investigated. The results showed that the fruit disease suppression of B. licheniformis W10 bacterial suspension and antifungal protein were significantly higher than that of the control. Inoculation of bacterial suspension and antifungal protein prior to M. fructicola gave a better biocontrol effect，and the higher concentrations of bacterial（1 × 1010 cfu · mL-1）and antifungal protein（3.0 mg · mL-1）performed better control effects. The environmental conditions，such as temperature and humidity，affected biocontrol effects of W10 bacterial suspension and antifungal protein. The influence of environment conditions on the activity of antifungal protein was less than that on bacterial suspension. Moreover，lower temperature（4 ℃）and relative humidity（RH 70%–75%）were favorable to prevent peach brown rot by W10 bacterial suspension and its antifungal protein. The W10 bacterial suspension and antifungal protein amended withcalcium[0.1% Ca(NO3)2] could enhance the biocontrol effects，and obviously put off the occurrence of peach brown rot. In addition，the bacterial suspension and antifungal protein significantly reduced the natural decay rates of peach fruits during storage，and the effects were equal to carbendazim. Moreover，both W10 bacterial suspension and antifungal protein treatments did not have effects on external and internal fruit appearance，such as chromatic aberration parameter L* of flesh，flesh firmness，soluble solids content and weight loss. Therefore，the B. licheniformis W10 is a potential biocontrol factor for peach brown rot.

Key words: peach, Bacillus licheniformis, antifungal protein, Monilinia fructicola, biological control, fruit quality