中国农业科学 ›› 2009, Vol. 42 ›› Issue (12): 4390-4395 .doi: 10.3864/j.issn.0578-1752.2009.12.034

• 研究简报 • 上一篇    下一篇

低温对烟草叶片中蔗糖向顶端分生组织转运的影响

石永春,刘卫群,王小彦

  

  1. (国家烟草栽培重点实验室)
  • 收稿日期:2009-04-02 修回日期:2009-06-30 出版日期:2009-12-10 发布日期:2009-12-10
  • 通讯作者: 刘卫群

Effect of Low Temperature on Sucrose Transportation from Leaves to Apical Meristem in Tobacco

SHI Yong-chun, LIU Wei-qun, WANG Xiao-yan
  

  1. (国家烟草栽培重点实验室)
  • Received:2009-04-02 Revised:2009-06-30 Online:2009-12-10 Published:2009-12-10
  • Contact: LIU Wei-qun

摘要:

【目的】探讨低温胁迫下蔗糖对烟草成花诱导的影响,研究低温条件下烟株中的蔗糖在不同组织中的积累、转运及转运流向。【方法】4℃处理栽培烟草K326 24 h后,检测不同部位组织的蔗糖含量、糖代谢关键酶及其基因表达水平;蔗糖转运蛋白(SUT1)基因表达水平;H2O2含量和抗坏血酸库氧化还原趋势。【结果】与正常培养的对照材料相比,低温处理后蔗糖含量在叶、叶柄、茎和顶端分生组织中呈梯度增大;叶中的蔗糖磷酸合成酶(SPS)活性升高,转化酶(Ivr)活性没有显著变化;淀粉酶活性被明显抑制,淀粉含量增加;叶片中SPSC基因、侧脉中SUT1基因表达水平上调,同时叶中H2O2含量升高,侧脉、叶柄、茎和顶端分生组织中抗坏血酸库趋于氧化态。【结论】低温诱导细胞内环境趋于氧化态势,提高了SUT1的装卸载能力,促进了蔗糖从叶片向顶端分生组织的转运。

关键词: 烟草, 低温, 蔗糖转运, 基因表达, 顶端分生组织

Abstract:

【Objective】 To investigate the potential effects of sucrose on floral induction of tobacco, the contents and transportations of sucrose in different tissues were studied in tobacco treated with low temperature. 【Method】 After treatment with 4℃ for 24 h, the sucrose and H2O2 contents, the gene expression levels and activities of SPS and SUT1, and the redox states of ascorbate pool in different tissues of tobacco were analyzed in treated and control plants. 【Result】 In low temperature treated plants, sucrose contents increased gradually in leaves, petioles, stems and apical meristem. The activities of SPS increased and that of amylase decreased, respectively, and starch contents increased in leaves. The up-regulated expressions of SPSC in leaves and SUT1 in lateral vein were found. Moreover, the increased H2O2 contents, the tendency for ascorbate to oxidize in lateral vein, petiole, stem and apical meristem were also observed. 【Conclusion】 The results suggested that the sucrose transportation from leaves to apical meristem was enhanced by low temperature, resulting from the stimulated loading and unloading of SUT1 in phloem by the oxidation tendency in cytosolic circumstance.

Key words: tobacco, low temperature, sucrose transportation, gene expression, apical meristem