低温对仁用杏雌蕊抗坏血酸-谷胱甘肽循环的影响低温对仁用杏雌蕊抗坏血酸-谷胱甘肽循环的影响

 利用人工智能模拟霜箱，设8 个温度（18、–1、–2、–3、–4、–5、–6、–7 ℃），对 抗寒性不同的两个仁用杏（Prunus armeniaca Linn.）品种雌蕊的过氧化氢（H₂O₂）含量和抗坏血酸-谷胱 甘肽（AsA-GSH）循环进行了研究。结果表明，低温胁迫增加了仁用杏雌蕊H₂O₂ 含量，–7 ℃时抗晚霜 品种‘围选1 号’和晚霜敏感品种‘龙王帽’分别为对照（18 ℃）的 5.49 倍和7.22 倍。低温期间，‘围 选1 号’雌蕊AsA 等酶含量及APX 等酶活性均高于‘龙王帽’，–7 ℃时，‘围选1 号’雌蕊AsA、MDHA、 DHA、GSH 和GSSG 含量比对照分别下降了66%、69%、48%、52%、53%，‘龙王帽’下降了78%、79%、 59%、66%、65%，–7 ℃时，‘围选1 号’雌蕊APX、MDHAR、DHAR、GPX、GR 活性、AsA/DHA、 GSH/GSSG 分别是对照的2.87 倍、1.07 倍、1.42 倍、1.60 倍、1.20 倍、65%和1.03 倍，‘龙王帽’是对照 2.41 倍、96%、1.13 倍、1.08 倍、98%、54%、97%。结果表明‘围选1 号’雌蕊在低温期间有较高的AsA-GSH 循环效率，可有效抑制H₂O₂ 的积累，这可能是其抗晚霜能力较强的重要原因之一。

Effects of Low Temperature Stress on Ascorbate-glutathione Cycle in Kernel Apricot Pistil

The peroxide（H₂O₂ ）content and ascorbate（AsA）-glutathione（GSH）cycle in pistil of two kernel apricot（Prunus armeniaca Linn.）cultivars under different low temperature（18，–1，–2， –3，–4，–5，–6，–7 ℃）were studied using the artificial climate chamber. The results show that H₂O₂ contents in kernel apricot pistilincreased under the low temperature stress，at–7 ℃，the amount of ‘Weixuan 1’resistant to cold stress was 5.49 times more than control（18 ℃），the amount of ‘Longwangmao’ susceptible to cold stress was 7.22 times more than the control. The content of enzyme like AsA and so on and activity of enzyme like APX and so on in‘Weixuan 1’pistil were higher than those in ‘Longwangmao’under low temperature，at–7 ℃，the contents of AsA，MDHA，DHA，GSH and GSSG were decreased by 66%，69%，48%，52%，53% compared to the control（18 ℃）in‘Weixuan 1’ pistil，were decreased by 78%，79%，59%，66%，65% compared to control（18 ℃）in‘Longwangmao’ pistil. At–7 ℃，the activity of APX，MDHAR，DHAR，GPX，GR，GSH/GSSG were 2.87，1.07， 1.42，1.60，1.20，1.03 times more than control（18 ℃）respectively. AsA/DHA was 65% of the control in‘Weixuan 1’pistil. The activity of APX，DHAR，GPX were 2.41，1.13，1.08 times more than control （18 ℃）. MDHAR，GR，AsA/DHA，GSH/GSSG were 96%，98%，54%，97% of the control respectively in‘Longwangmao’pistil. The results indicate that‘Weixuan 1’pistil could maintain efficient metabolism of AsA-GSH cycle，inhibit the accumulation of H₂O₂  effectivity，this might be one of important reasons for higher cold tolerance of‘Weixuan 1’.