采后一氧化氮处理对油桃抗软腐病的诱导

Induced resistance to Rhizopus rot(Rhizopus stolonifer) in nectarine fruit by postharvest treatment with nitric oxide

以油桃为实验对象,研究了采后NO供体硝普钠(SNP)处理对低温贮藏期间油桃根霉软腐病的控制效果及其机理。研究结果表明硝普钠处理能显著地抑制损伤接种Rhizopus stolonifer的油桃果实软腐病的扩展,其中较低浓度5mmol/L的硝普钠处理效果最好,其病斑直径仅为对照的75.83%。进一步研究表明SNP浸泡处理能显著地提高低温贮藏期间油桃果实组织苯丙氨酸解氨酶(PAL)和过氧化物酶(POD)的活性,且在贮藏后期对组织过氧化氢酶(CAT)和超氧化物歧化酶(SOD)酶活性具有抑制作用,然而对多酚氧化酶(PPO)的活性没有明显的诱导作用。可见一氧化氮是通过改变油桃抗性相关酶的活性来增强果实的抗病性。

Control effect of sodium nitroprusside（SNP）treatment on Rhizopus rot of nectarine fruit during storage at low temperature and its mechanism were studied.The result showed that postharvest SNP treatment significantly inhibited the development of Rhizopus rot in nectarine fruit inoculated with Rhizopus stolonifer,relative lower concentration of SNP at 5 mmol/L had the best control effect,and its lesion diameter was only 75.83% of the control.Meanwhile activity of phenylalanine ammonia lyase（PAL）,peroxidase（POD）in nectarine tissue were significantly increased during whole storage,catalase（CAT）and superoxide dismutase（SOD）were inhibited by SNP treatment during later storage,but SNP did not stimulate polyphenoloxidase（PPO）activity.These findings suggested that NO might enhance disease resistance of nectarine through changing resistant-related enzyme activities.