摘要
【目的】研究不同价态和浓度硒对甜樱桃叶片褪黑素含量以及谷胱甘肽(GSH)氧化还原循环的影响,为探究外源硒、内源褪黑素和GSH氧化还原循环间的关系提供参考。【方法】2015年在四川广元进行田间试验,以两年生甜樱桃‘红蜜’和‘布鲁克斯’为试验材料,试验包括清水处理(CK)、单施Se^(6+)(来源于Na_2SeO_4)、单施Se^(4+)(来源于Na_2SeO_3)、Se^(6+)+褪黑素和Se^(4+)+褪黑素5个处理,30 d后采取叶片,测量叶片硒含量和褪黑素的含量。2016年以重庆綦江两年生甜樱桃‘布鲁克斯’叶片为试验材料进行离体试验,将甜樱桃离体叶片放置在2 mg·L^(-1) Se^(6+)处理0、1、2、3和4 d,以清水处理为对照,每天上午10:00采取叶片;将离体叶片分别置于0、0.5、1.0、2.0、4.0 mg·L^(-1) Se^(6+)溶液24 h后采取叶片,离体试验分别测量叶片硒和褪黑素的含量以及GSH氧化还原循环的物质和酶活性。【结果】田间试验中,2.0 mg·L^(-1) Se^(4+)和Se^(6+)处理显著降低了‘红蜜’和‘布鲁克斯’甜樱桃叶片褪黑素含量,且两种甜樱桃叶片褪黑素含量在Se^(6+)+褪黑素和Se^(4+)+褪黑素处理下分别比单施Se^(6+)和单施Se^(4+)处理高。离体试验中,硒处理第1天‘布鲁克斯’离体叶片褪黑素含量高于对照,之后低于对照且随着时间延长而逐渐降低。硒处理第1天迅速降低了GSH氧化还原循环的物质和酶活性,即GSH、氧化性谷胱甘肽(GSSG)、GSH+GSSG和GSH/GSSG比值低于对照,谷胱甘肽过氧化物酶(GPX)和谷胱甘肽还原酶(GR)活性也低于对照,之后随着时间的延长,GSH氧化循环效率升高并超过对照。在不同浓度Se^(6+)处理24 h下,Se^(6+)处理增加了叶片褪黑素的含量,且随着浓度的增加而增加,GSH氧化循环效率则呈下降的趋势。【结论】外源硒处理提高了甜樱桃叶片硒含量,且六价硒的效果显著高于四价硒。外源硒处理影响甜樱桃褪黑素的含量和GSH氧化还原循环。
【Objective】To explore the relationship among exogenous selenium, endogenous melatonin, and glutathione oxidation cycle, the effects of selenium valence states and concentrations on melatonin content and glutathione（GSH） redox cycle efficiency in sweet cherry leaves were studied.【Method】Field experiments were carried out at Guangyuan, Sichuan in 2015. Two-year old sweet cherry of ‘Hongmi＇ and ‘Brooks＇ in orchard were chosen as the experimental materials. Five treatments of water treatment（CK）, Se^（6＋）（from Na_2SeO_4）, Se^（4＋）（from Na_2SeO_3）, Se^（6＋） ＋ melatonin, Se^（4＋） ＋ melatonin were designed. The leaves were collected and ground to measure the contents of Se and melatonin after treated 30 days. The vitro experiments were carried out in 2016, and the leaves of two-years old ‘Brooks＇ in orchard at Qijiang, Chongqing were selected as materials. For the different treated time experiments, the leaves were placed in 2 mg·L^（-1） se^（6＋） for 0, 1, 2, 3 and 4 days, and water treatment as control（CK）, and the leaves were collected at 10：00 am. every day. For the different Se concentrations treatments, sweet cherry leaves were placed in 0, 0.5, 1.0, 2.0 and 4.0 mg·L^（-1） se^（6＋） solution for 24 hours and then collected the leave samples. The contents of selenium and melatonin, and substances and enzymes in glutathione redox cycle of all collected samples were measured. 【Result】Leaves melatonin contents of ‘Hongmi＇ and ‘Brooks＇ under Se^（4＋） or Se^（6＋） treatments were significantly reduced under field experiment. While leaves melatonin contents of two varieties sweet cherry under Se^（6＋）＋ melatonin or Se^（4＋）＋ melatonin treatments were higher than only Se^（4＋） or Se^（6＋）treatments, respectively. For different time vitro treatment, leaves melatonin contents under Se^（6＋） treatment was significantly higher than control at the first day, but the contents were become lower than water control at 2, 3 and 4 days. At the same time, vitro leaves under 2 mg·L^（-1） Se^（6＋） concentration for 24 h reduced GSH redox cycle efficiency at first day, via the contents of GSH, oxidative glutathione（GSSG）, GSH＋GSSG and GSH/GSSG ratio were all lower than control, and the activities of peroxidase（GPX） and glutathione reductase（GR） were also lower than control. But after that GSH redox cycle efficiency started to increase and was higher than control. For different selenium concentrations treatments, the vitro leaves melatonin contents and GSH redox efficiency were reduced with the increased Se^（6＋） concentrations. 【Conclusion】The selenium contents in leaves of sweet cherry were improved by exogenous selenium treatment, especially the Se^（6＋） treatment. And selenium treatments affected the leaves melatonin contents and the efficiency of GSH redox cycle.
出处
《中国农业科学》
CAS
CSCD
北大核心
2017年第22期4373-4381,共9页
Scientia Agricultura Sinica
基金
重庆市基本科研业务费(2015cstc-jbky-00514
2016cstc-jbky-00514)
长江师范学院引进人才科研启动项目(2017KYQD65)
