INFLUENCE OF SALICYLIC ACID TREATMENT ON POSTHARVEST QUALITY AND GRAY MOLD OF STRAWBERRY FRUIT

We studied the influences of different concentrations of salicylic acid(SA) on postharvest quality of strawberry fruits,gray mold in storage period and content of disease-resistant substances. The results showed that the treatment with different concentrations of salicylic acid could keep the postharvest quality of strawberry fruits to different extents,could inhibit mycelial growth as well as spore germination of Botrytis cinerea,and could significantly lower the incidence rate of gray mold caused by infection;and the antibacterial effect was in positive correlation with the SA concentration. Additionally,SA treatment could influence the content of disease-resistant substances in the postharvest strawberry fruits. At the initial stage of storage(one day),the lignin content and phenylalanine ammonia lyase(PAL) activity in the strawberry fruits treated with SA(10 mmol/L and 5 mmol/L)were remarkably higher than those of the control(P0.05). In the whole storage period,the catalase(CAT)activity was suppressed;and peroxidase(POD) activity was improved. Therefore,SA treatment could control activities of enzyme related to disease resistance and could delay deterioration of strawberry fruits.