The effect of mepiquat chloride on elongation of cotton (Gossypium hirsutum L.) internode is associated with low concentration of gibberellic acid
The effect of mepiquat chloride on elongation of cotton (Gossypium hirsutum L.) internode is associated with low concentration of gibberellic acid
复制标题
缩节胺对棉花（Gossypium hirsutum L.）节间伸长的影响与低浓度赤霉酸有关
DOI：
10.1016/j.plantsci.2014.05.005
复制
发表时间：
2014-08-01
期刊：
影响因子：
5.2
通讯作者：
Li, Zhaohu
中科院分区：
文献类型：
--
作者：
Wang, Li;Mu, Chun;Li, Zhaohu
生长调节剂缩节胺（MC）在全球范围内用于棉花（Gossypium hirsutum L）冠层操作以避免过度生长和产量损失。然而，很少有信息是关于MC的植物结构的修改是否与赤霉酸（GA）代谢和信号转导的改变有关。在这里，GA代谢和信号转导的作用进行了研究在棉花幼苗与MC。MC显著降低了伸长节间内源GA（3）和GA（4）水平，通过下调GhEXP和GhXTH 2抑制细胞伸长，进而降低株高。MC处理后2-10 d，GA生物合成和代谢相关基因的表达均受到明显抑制，同时也下调了DELLA样基因的表达。在MC处理的早期，GA生物合成和代谢相关基因的表达明显上调，表现出明显的反馈调节作用。缩节胺作用受时间转运和空间积累控制，通过调节GA生物合成和信号表达维持GA稳态。结果表明，施用MC可通过调控GA生物合成和代谢基因的表达，降低棉花内源GA水平，从而抑制细胞伸长，缩短节间，降低株高。(C)2014爱思唯尔爱尔兰有限公司版权所有。
The growth regulator mepiquat chloride (MC) is globally used in cotton (Gossypium hirsutum L) canopy manipulation to avoid excess growth and yield loss. However, little information is available as to whether the modification of plant architecture by MC is related to alterations in gibberellic acid (GA) metabolism and signaling. Here, the role of GA metabolism and signaling was investigated in cotton seedlings treated with MC. The MC significantly decreased endogenous GA(3) and GA(4) levels in the elongating internode, which inhibited cell elongation by downregulating GhEXP and GhXTH2, and then reducing plant height. Biosynthetic and metabolic genes of GA were markedly suppressed within 2-10 d of MC treatment, which also downregulated the expression of DELLA-like genes. A remarkable feedback regulation was observed at the early stage of MC treatment when GA biosynthetic and metabolic genes expression was evidently upregulated. Mepiquat chloride action was controlled by temporal translocation and spatial accumulation which regulated GA biosynthesis and signal expression for maintaining GA homeostasis. The results suggested that MC application could reduce endogenous GA levels in cotton through controlled GA biosynthetic and metabolic genes expression, which might inhibit cell elongation, thereby shortening the internode and reducing plant height. (C) 2014 Elsevier Ireland Ltd. All rights reserved.