短时间高温处理下桃芽酚类物质及相关酶活性与休眠解除的关系

以6年生曙光油桃、青州冬雪蜜桃为试材,研究40℃、45℃、50℃短时间处理对桃芽自然休眠的调控效应。结果表明:短时间高温处理对桃芽自然休眠的调控效应因处理时期、处理温度和处理持续时间长短的不同而异。11月30日短时间高温处理中,40℃高温处理对桃芽自然休眠的解除具有负调控效应,并且调控效应随处理时间的延长而增强;45℃和50℃高温处理对桃芽自然休眠的解除呈正调控效应,调控效应随处理时间的延长而增强,虽然随着处理温度的升高和处理持续时间的延长,部分桃芽死亡,但是在存活芽中短时间高温对桃芽休眠解除作用明显增强。12月10日高温处理中,40℃高温处理对桃芽自然休眠解除的调控效应不明显,45℃和50℃高温处理和11月30日高温处理相同,只是前者的调控效果优于后者。不同高温处理桃芽的萌芽级数和总酚含量之间的相关性分析表明,总酚含量的降低可能是高温解除休眠的原因。

Relationship between total phenolics content, related enzymes activity and dormancy release in peach bud treated by short-term heating

Effects of short-term heating at 40℃,45℃,50℃ on bud livability, bud burst, the content of total phenolics and the activity of phenylalanine amino transferase(PAL), polyphenol oxidase(PPO),peroxidase(POD) enzyme in Shuguang nectarine cultivar bud were studied in order to know the mechanism of short-term heating releasing the endodormancy. The results indicated that effects of short-term heating on the release of endodormancy were advanced by delayed the treatment date, the raise of treatment temperature and the prolonging of treatment time. On 30 November, compared with non-heating treatment (CK), the date of endodormancy release was postponed, the bud burst, and the activity of PPO,POD were lower and the content of total phenolics and the activity of PAL were higher on 40℃-heating treatment. Whereas, 45℃ and 50℃-heating treatment had the contrary effects. On 10 December, 40℃-heating treatment nearly had the same results as CK on the above factors., and the effects of 45℃ and 50℃-heating treatment on endodormancy release were the same as the treatment on 30 November, and the effect of the former was superior to the latter. The correlation of the bud burst series and the content of total phenolics of the different treatments indicated that the decrease of total phenolics content was probably the cause of endodormancy release.