College of Horticulture, Northwest A&F University, Yangling, 712100, Shaanxi, China; Department of Life Sciences, Yuncheng University, Yuncheng, 044000, Shanxi, China.
J Sci Food Agric. 2013 Dec;93(15):3691-9. doi: 10.1002/jsfa.6195. Epub 2013 Jun 12.
To understand the mechanisms leading to the enhanced chilling tolerance of kiwifruit by low-temperature conditioning (LTC, 12 °C for 3 days), this study investigated the effect of LTC on chilling tolerance and changes in antioxidant enzyme activities and endogenous hormones.
LTC significantly alleviated chilling injury in kiwifruit. Fruits treated with LTC maintained lower respiration and ethylene production and higher firmness. Furthermore, this treatment inhibited the accumulation of malondialdehyde, superoxide radicals and hydrogen peroxide and the increase in membrane permeability and increased the activities of superoxide dismutase, catalase, ascorbate peroxidase and peroxidase under chilling stress. The treatment also maintained higher levels of endogenous abscisic acid (ABA), indole-3-acetic acid (IAA) and zeatin riboside (ZR), lower gibberellic acid (GA3) levels and higher ABA/GA3 and ABA/IAA ratios.
The results suggested that LTC alleviated chilling injury in kiwifruit by improving antioxidant enzyme activities and maintaining higher levels of endogenous ABA, IAA and ZR, lower GA3 levels and higher ABA/GA3 and ABA/IAA ratios.
为了了解低温处理（LTC，12°C 处理 3 天）增强猕猴桃抗冷性的机制，本研究探讨了 LTC 对猕猴桃抗冷性和抗氧化酶活性及内源激素变化的影响。
LTC 显著减轻了猕猴桃的冷害。经过 LTC 处理的果实呼吸和乙烯生成较低，硬度较高。此外，这种处理抑制了丙二醛、超氧自由基和过氧化氢的积累以及膜通透性的增加，并在冷胁迫下提高了超氧化物歧化酶、过氧化氢酶、抗坏血酸过氧化物酶和过氧化物酶的活性。处理还维持了较高水平的内源脱落酸（ABA）、吲哚-3-乙酸（IAA）和玉米素核苷（ZR），较低水平的赤霉素（GA3）和较高的 ABA/GA3 和 ABA/IAA 比值。
结果表明，LTC 通过提高抗氧化酶活性和维持较高水平的内源 ABA、IAA 和 ZR、较低水平的 GA3 和较高的 ABA/GA3 和 ABA/IAA 比值来减轻猕猴桃的冷害。
