苹果酸处理对苹果黑斑病的抑制及抗性酶的诱导

Inhibiting effect of postharvest malic acid treatment on Alternaria rot of apples and its partial mechanism

研究了采后25mmol·mL-1苹果酸处理对苹果黑斑病的影响.结果表明:苹果果实经25mmol·mL-1苹果酸处理再用链格孢(Alternaria alternata)损伤接种能够抑制病斑直径扩展;苹果酸处理增强了果实内苯丙氨酸解氨酶(PAL)、过氧化物酶(POD)和多酚氧化酶(PPO)的活性,酚类物质的含量也明显提高;A.alternata损伤接种可进一步增强苹果酸处理的PAL、POD和PPO活性,提高果实内总酚和类黄酮的含量.由此表明,苹果酸对苹果黑斑病的抑制作用与诱导果实内抗性酶的活性以及提高酚类物质的含量密切相关.

The effects of postharvest malic acid dipping at 25mmol·mL^-1 on Alternaria rot of apple inoculated with Alternaria alternate were studied in this paper. The results showed that malic acid treatment significantly inhibited development of lesion, increased activities of phenylalanine ammonialyase （ PAL） , peroxidase （POD） and polyphenoloxidase （PPO）, enhanced content of total phenolic and flavanoid. The treated fruit challenged with A. alternata increased furthermore activity of PAL, POD, PPO and content of total phenolic and flavanoid.It is suggested that the effective inhibition of malic acid treatment on Alternaria rot of apple fruit is associated with induction of defense enzyme activities and accumulation of total phenolic and flavanoid in treated fruits.