Phytic acid enhances biocontrol efficacy of Rhodotorula mucilaginosa against postharvest gray mold spoilage and natural spoilage of strawberries

Abstract

The control activity of Rhodotorula mucilaginosa, alone or in combination with phytic acid (PA) on gray mold spoilage and natural spoilage of strawberries was investigated. R. mucilaginosa as stand-alone treatment significantly reduced the disease incidence of gray mold spoilage of strawberries at 20 °C, and the combination of R. mucilaginosa and PA at the concentration of 4 mol/ml and 6 mol/ml were more effective than R. mucilaginosa alone treatment. In vitro test showed that PA at the concentration of 4 mol/ml and 6 mol/ml significantly enhanced the inhibition of the growth of Botrytis cinerea on PDA. PA at all the tested concentrations enhanced the growth of R. mucilaginosa in NYDB media. PA at the concentration of 4 mol/ml slightly increased the population growth of R. mucilaginosa in strawberry wounds at the first day at 20 °C, and slightly increased the population growth of R. mucilaginosa in fruit wounds at 4 °C at the whole storage time. The combination of R. mucilaginosa and PA at the concentration of 4 mol/ml was the most effective treatment in controlling the natural spoilage of strawberries following storage at 4 °C for 20 d followed by 20 °C for 5 d.