油桃芽高温处理后酚和活性氧与休眠解除的关系

Relationships of Total Phenolics, Reactive Oxygen Species and Dormancy Release in Nectarine Bud Treated by Heating

以6年生曙光油桃/青州冬雪蜜桃为试材,研究40℃、45℃、50℃高温短时间处理对油桃芽总酚含量、活性氧含量及相关酶活性和自然休眠解除的影响。结果表明:40℃高温处理对油桃芽自然休眠的解除具有负调控效应(11月30日)或效应不明显(12月10日),其萌芽级数、·OH(羟基自由基)和O2·(超氧阴离子自由基)产生速率、H2O2(过氧化氢)含量及POD(过氧化物酶)、CAT(过氧化氢酶)、PPO(多酚氧化酶)活性均低于对照(11月30日)或与对照无显著差异(12月10日),而总酚含量和PAL(苯丙氨酸解氨酶)、SOD(超氧化物歧化酶)活性高于对照(11月30日)或与对照差异不明显(12月10日);45℃和50℃高温处理对油桃芽自然休眠的解除呈正调控效应,其萌芽级数、·OH和O·2产生速率、H2O2含量及POD、CAT、PPO活性与对照相比明显升高,而总酚含量和PAL、SOD活性显著降低,虽然部分花芽和叶芽因高温处理而死亡,但是在存活芽中短时间高温对油桃芽自然休眠解除的促进作用明显增强。总酚含量的降低和活性氧的迅速增加可能是高温解除自然休眠的原因。

Effects of short-term heating at 40℃, 45℃ and 50℃ on bud livability, bud burst, the content of reactive oxygen and total phenolics, and the activity of related enzyme in ’Shuguang＇ nectarine bud were studied in order to investigate the mechanism of short-term heating releasing the endodormancy. The results indicated that effects of short-term heating on the endodormancy were different with date, temperature and continuous time of treatment. On November 30, compared with no-heating treatment （ control）, the date of endodormancy release was postponed, the bud burst series and the rate of production in O2^·- and · OH, the content of H2O2 and the activity of CAT, POD, PPO enzyme were lower, and the content of total phenolics and the activity of PAL, SOD enzyme were higher on 40℃-heating treatment. Whereas, 45℃ and 50℃-heating treatment had the contrary effects. On December 10, 40℃-heating treatment nearly had the same results as control on the above factors, and the effects of 45℃ and 50℃-heating treatment on endodormancy release were the decrease rate were same as the treatment on 30 November, and the effect of the former was superior to the latter. The of the total phenolics content and the significant increase of reactive oxygen content and production probably the cause of endodormancy release