Temperature and Ultra Low Oxygen Effects and Involvement of Ethylene in Chilling Injury of 'Rojo Brillante' Persimmon Fruit

The effects of storage temperature, inhibition of ethylene action by treatment with 1-methylcyclopropene (1-MCP) and ultra low oxygen (ULO) atmosphere on chilling injury (CI), fruit firmness and ethylene production in the astringent 'Rojo Brillante' persimmon fruit were investigated. CI symptoms were manifested as a very dramatic loss of firmness after fruit transfer from cold storage to shelf-life conditions (18 degrees C). During cold storage, fruit softening appeared more rapidly in fruit stored at the intermediate temperature of 10 degrees C than at 1 degrees C or 14.5 degrees C. Ethylene production increased with storage time at the chilling temperature (1 degrees C) but a sharp increase took place upon fruit transfer from 1 degrees C to ambient temperature. This ethylene increase was accompanied by a loss of fruit firmness associated with chilling damage development. A pre-treatment with the competitive inhibitor of ethylene action 1-MCP, at 1 mu L/L, reduced firmness loss and mitigated CI damage but considerably increased ethylene production in fruit transferred to shelf-life conditions after a prolonged cold storage period. Collectively, these results suggest a role of ethylene in the reduction of flesh firmness and consequently in the induction of CI in persimmon fruit. Moreover, ethylene exerts a negative feedback regulation of cold-induced ethylene biosynthesis. Storage of 'Rojo Brillante' persimmon fruit under ULO (1.3-1.8% O-2, v/v) atmosphere did not affect the incidence of CI but reduced fruit astringency, suggesting that ULO may be an alternative postharvest storage system for 'Rojo Brillante' persimmon fruit.