Preliminary evaluations of postharvest organic treatments against Monilinia and Botrytis cherry decay
Postharvest fungal rots are the limiting factor in the storage and marketing of sweet cherry fruit, where the major decay organisms are Monilinia fructicola (cause of brown rot) and Botrytis cinerea (cause of gray mold). Postharvest decay can be controlled with postharvest fungicides, but many countries do not have registered postharvest treatments and consumers prefer organic postharvest treatments. In these experiments, a range of organic treatments (a combination of potassium bicarbonate with potassium silicate, a rhamnolipid biosurfactant, a fatty acid soap, and a combination of these treatments) were assessed for their efficacy at 20°C over 7 days on sweet cherry fruit infected with either M. fructicola or B. cinerea. The results from the preventative experiment showed there were significantly lower levels of rot due to Botrytis infection when fruit were dipped in the fatty acid soap while the rhamnolipid treatment also reduced rots due to both fungi at 3 days. Fruit quality was also assessed and a significant negative effect of the combination of potassium bicarbonate with potassium silicate was observed. All treatments from the second experiment failed to significantly reduce fruit rots caused by M. fructicola. These results show limited promise at suppressing postharvest cherry rots and it appears that alternative treatments or combinations of treatments, possibly with physical treatments, are needed to reduce the incidence of decay during storage.
Golding, J.B., Lidbetter, F. and Tesoriero, L. (2021). Preliminary evaluations of postharvest organic treatments against Monilinia and Botrytis cherry decay. Acta Hortic. 1325, 333-338
sweet cherry, decay, postharvest