한국산 양파의 부패원인균 확인 및 Botrytis 부패에 대한 온도, 습도 및 훈증처리의 영향

Confirmation of Saprophytes of Onions in Korea and Effects of Temperature, Humidity and Fumigation on Boyrytis-rot.

산지 저 장고로부터 채취한 부패양파의 부패원인균을 조사한 결과, 곰팡이로써는 Botrytis, Peniciliium 및 Fusarium이 주종이었으며 세균으로써는 Erwinia 및 Pseudononas가 주종이었고, 이중Pseudomonas는 비병원성 부패균이었다. 분리균중 저장양파에 가장 큰 피해를 주는 Botrytis가 유발시키는 회색곰팡이병에 대해 온도, 습도 및 Tetrachloro isophthalonitrile훈증처리의 억제효과를 실험한 결과, 온도의 효과가 가장 큰 것으로 나타났으며. $0^{\circ}C$에서 접종인편이 50% 부패하는데 걸리는 일수는 26.2일로써 $25^{\circ}C$에서보다 부패를 21.8일 지연시켰다. 습도의 경우에는 $0^{\circ}C$에서 상대습도 70%의 50%부패하는데 걸리는 일수는 28.0일로써 90%의 경우보다 부패를 1.8일 지연시켰다. 훈증처리의 효과는 $0^{\circ}C$, 상대습도 70%에서 가장 컸으며, 90%의 경우보다 부패를 3.8일 더 지연시켰다. 이병인편에 있어서는 억제효과가 둔화되거나 소실되어 저장양파의 초기상태가 극히 중요함을 나타내었다.

Saprophytic microorganisms of onion bulbs in Korea were confirmed, and effects of temperature, humidity and fumigation by Tetrachloro isophthalonitrile on Botrytis-rot were investigated in order to decrease storage loss of onions. Dominant saprophytes were Botrytis, Penicillium and Fusarium as molds which were all pathogens, and Erwinia and Pseudomonas as bacteria of which Pseudomonas was a non-pathogen. Botrytis-rot was most effectively suppressed by temperature. At $0^{\circ}C$, the incubation days at which 50% area of one onion leaf-fragment (2.5$\times$2.5cm) inoculated by Botrytis was rotten were 26.2 days and the rotting was delayed more by 21.8 days than at $25^{\circ}C$. For humidity, the effect was pretty insignificant in contrast with temperature effect. At RH 70% and $0^{\circ}C$, the incubation days at which 50% area of one onion leaf-fragment was rotten were 28.0 days and the rotting was delayed more by 1.8 days than at RH9o% and $0^{\circ}C$. By fumigation, the rotting was delayed by 3.8 days at RH 70% and $0^{\circ}C$. In case of slightly infected samples, temperature effect was reduced and the effects of humidity and fumigation were ignored, which implies that storage samples should be healthy.