低溫檢疫處理引起之椪柑果皮傷害

Rind Injury Caused by Low-temperature Quarantine Treatment in 'Ponkan' Mandarin (Citrus reticulata Blanco)

經過三年的觀察試驗發現椪柑低溫檢疫處理容易引起果皮的低溫傷害。在一次的輸日椪柑樣品觀察中，47個椪柑在移出處理庫後5日就出現22果有傷害徵狀。在實驗室模擬低溫檢疫處理試驗採用0°～1℃處理15日，共做5次試驗，每次每處理80果，獲得如下的結果。（1）採收後翌日或5日內進行低溫處理者極少發生傷害；採收後10日才進行處理者傷害發生頻率增高；採收後15日才進行處理者每次試驗皆有一部分果實受傷。（2）受傷徵狀大都在低溫處理後移置15℃5日內出現，其後不再顯著增加傷害果數，但可使輕度傷害的果實加重其徵狀，甚至腐爛。本文並詳細敘述輕度、中度、重度傷害之徵狀，且對外銷椪柑處理作業上可用以避免或減低傷害之策略提供實用建議。

Repeated observations were made on the occurance and symptoms of rind injury caused by low-temperature quarantine treatment in 'Ponkan' mandarin (Citrus reticulata Blanco). Light, medium, and severe injury symptoms were described. Simulated low-temperature quarantine treatment at 0°~1℃ for 15 days targeted at Oriental fruit flies did not cause significant injury to 'Ponkan' mandarin when the treatment commenced within 5 days after harvest. Injury occurred to some fruit receiving similar treatment when the treatment began from 10 to 15 days after harvest. Injury symptoms developed within 5 days after the treatment when the treated fruit was kept at 15° or 20℃. Keeping the low-temperature treated fruit at 15℃ for additional 10 days and/or at 20℃ for additional 7 days did not significantly increase the number of fruits injured but worsened certain light-injury symptoms.