纯氧对采后杨梅果实腐烂的抑制与抗病相关酶的诱导

Inhibition of Postharvest Decay and Induction of Defensive Enzymes by Pure Oxygen in Chinese Bayberry Fruit

为研究高氧对抑制果实腐烂的作用及其与抗病相关酶活性诱导的关系,将杨梅果实采后在5℃用纯氧或空气(对照)处理12d。结果表明,纯氧处理可显著抑制果实腐烂发生,贮藏12d后对照果实的腐烂指数达到54%,而处理果实仅为17%。纯氧处理在贮藏前期可诱导杨梅果实几丁质酶和β-1,3-葡聚糖酶活性的升高,并在第6天时达到高峰。另外,纯氧处理增加了苯丙氨酸解氨酶和过氧化物酶的活性及总酚含量,并在整个贮藏期间一直高于对照水平。这些结果表明,高氧抑制杨梅果实腐烂的作用与诱导与抗病相关的酶的活性升高密切相关,抗病性诱导是高氧抑制杨梅果实腐烂的重要原因。

Chinese bayberry fruits were stored in air （control） or pure oxygen atmosphere for up to 12 days at 5℃ to investigate the effects of high oxygen on decay control and its relation to the induction of defensive enzyme activities. The results showed that exposure of Chinese bayberry to pure oxygen significantly prevented fruit decay. At the end of the storage period, the decay index of fruits exposed to pure oxygen was only 17% while that of control fruits reached 54% （Fig. 1）. Pure oxygen caused a significant increase in chitinase and β-1,3-glucanase activities which reached a peak on the 6th day of storage （Fig.2）. Phenylalanine ammoniumlyase （Fig.3A） and peroxidase （Fig.4） activities as well as total phenolic content （Fig.3B） increased more quickly and stayed at significantly higher levels in fruits exposed to pure oxygen during storage than the control fruits. These results suggest that the inhibition of postharvest fruit decay by high oxygen was related to the induction of defensive enzyme activities. The induced disease resistance may be involved in the mechanisms by which high oxygen treatment inhibited fruit decay in Chinese bayberry.