低温在诱导油桃芽解除休眠过程中对代谢的影响

Metabolic changes during low temperature induced dormancy release in 'NJ72' nectarine (Prunus persica L. Batsch).

果树温室栽培时常出现萌芽率低,萌芽开花延迟,花器官发育差,座果率低等问题。调查了分批移入人工气候室的“NJ72”油桃萌芽率,以确定其休眠解除时间,试验结果表明“NJ72”油桃于1月中旬结束休眠,不同温度处理对“NJ72”油桃休眠期代谢的影响不同,低温促进花芽内H_2O_2的积累,同时促进过氧化氢酶(CAT)、超氧物岐化酶(SOD)、过氧化物酶(POD)活性的提高,低温处理使花芽呼吸速率增加,其中磷酸戊糖途径(PPP)代谢增加,糖酵解(EMP)降低,而三羧酸循环(TCA)代谢波动较小,葡萄糖-6-磷酸(G-6-PDH)脱氢酶活性也有所增加。

From mid-Oct. to mid-Feb. ,2-year old potted 'NJ72' nectarine(Prunus persica L. Batsch) was transferred at certain intervals from field to the growth chamber at 25℃ to determine the end of bud dormancy. The results show that bud dormancy of 'NJ72' is broken by mid-Jen. The process of the onset of dormancy differs greatly among the leaf and flower buds. The intensity of dormancy is lower in the flower buds compared to that in the leaf buds. In flower buds of peaches treated with low temperature,endogenous peroxide content increases soon after treatment. Catalase activity is shown to increase significantly during chilling and coincides with the increase of the activity of peroxidase and superoxide dismutase. Accumulation of peroxide is accompanied with an increase of peroxidase activity,probably due to substrate adaptability. The rate of respiration of flower buds increases at low temperature during dormancy, among which the rate of the pentose phosphate pathway is also increased, while the rate of the embden-meyerhof pathway decreases and the rate of tricarboxlic acid cycle changes little. Concomitantly,glucose 6-phosphate dehydrogenase activity increases at low temperature during dormancy.