Effects of Exogenous GA3 and DPC Treatments on Levels of Endogenous Hormone and Expression of Key Gibberellin Biosynthesis Pathway Genes During Stem Elongation in Sugarcane
Effects of Exogenous GA3 and DPC Treatments on Levels of Endogenous Hormone and Expression of Key Gibberellin Biosynthesis Pathway Genes During Stem Elongation in Sugarcane
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外源GA(3)和DPC处理对甘蔗茎伸长过程中内源激素水平和关键赤霉素生物合成途径基因表达的影响
DOI：
10.1007/s12355-019-00728-7
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发表时间：
2019-12-01
期刊：
影响因子：
1.9
通讯作者：
Li, Yang-Rui
中科院分区：
文献类型：
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作者：
Qiu, Li-Hang;Chen, Rong-Fa;Li, Yang-Rui
甘蔗的节间伸长决定了株高，而株高又影响甘蔗产量。本研究旨在探讨植物生长调节剂赤霉酸（GA（3））及其抑制剂氯化二甲基哌啶（DPC）对甘蔗节间伸长的调控机制。以清水为对照，在新梢伸长初期叶面喷施GA（3）或DPC。在处理后第3、6、12和24天测定甘蔗叶片内源激素含量和GA 20 ox 1、GID 1和GAI的表达。结果表明，与对照相比，GA（3）处理的甘蔗植株的高度显示出显著的增加，而DPC处理的植株则观察到相反的趋势。与对照相比，赤霉素（GA（3））处理的植株叶片中赤霉素（GAs）含量显著增加，吲哚乙酸（IAA）含量则呈现先增加后下降，最后趋于稳定的趋势。GA（3）处理的植株叶片中细胞分裂素（CTK）、脱落酸（阿坝）和乙烯（ETH）含量与对照相比呈显著下降趋势。DCP处理后，叶片中阿坝和ETH含量显著增加，IAA和GAs含量显著降低，CTK含量呈现先降低后升高的趋势。GA（3）处理后，GA 20 ox 1和GID 1基因的表达量先上升后下降，而GAI基因的表达量先下降后稳定。DPC处理后，GA 20 ox 1的表达量呈现先降低后升高的趋势，而GID 1的表达量呈现先降低后稳定的趋势，GAI的表达量呈现先升高后稳定的趋势。结果表明，外源GA（3）处理促进甘蔗节间伸长主要是通过提高内源GA含量，降低阿坝和ETH含量，调节GA 20 ox 1、GID 1和GAI基因的表达; DPC处理主要是增加阿坝和ETH的含量，降低GAs和IAA的含量，从而抑制了GID 1的表达，促进GAI的表达，最终抑制甘蔗节间的伸长。
Internode elongation determines plant height, which in turn affects the cane yield in sugarcane. This study aimed to explore the mechanisms of sugarcane internode elongation regulation by plant growth regulators, gibberellic acid (GA(3)) and its inhibitor 1, 1-dimethylpiperidinium chloride (DPC, also called mepiquat chloride). We sprayed GA(3) or DPC on the leaves at the early shoot elongation stage with water as the control. The contents of endogenous hormones and the expression of GA20 ox1, GID1, and GAI in sugarcane leaves were measured at days 3, 6, 12, and 24 after treatment. It was found that the height of sugarcane plants treated with GA(3) showed a significant increase compared to the control, whereas an opposite trend was observed in the DPC-treated plants. Compared to the control, the content of gibberellins (GAs) in leaves was increased significantly, while the indole acetic acid (IAA) content showed an initial increase, then a decline, and eventually remained stable in the GA(3)-treated plants. The contents of cytokinins (CTK), abscisic acid (ABA), and ethylene (ETH) in leaves exhibited a significant downward trend in the GA(3)-treated plants compared to the control. In the DCP-treated plants, however, the levels of ABA and ETH in leaves were significantly increased, IAA and GAs significantly decreased, and CTK showed a trend of an initial decline followed by an increase. After GA(3) treatment, the gene expression levels of GA20 ox1 and GID1 in sugarcane increased first then decreased, whereas the gene expression level of GAI first decreased and then stabilized. After DPC treatment, the expression of GA20 ox1 in sugarcane showed an initial decrease followed by an increase, while the expression of GID1 decreased gradually and then stabilized, and the expression of GAI showed a trend of an initial increase followed by stabilization. The results of the present study indicate that exogenous GA(3) treatment stimulated the internode elongation in sugarcane mainly by increasing the endogenous levels of GAs, decreasing the levels of ABA and ETH, and regulating the expression of GA20 ox1, GID1 and GAI genes; the DPC treatment mainly increased the contents of ABA and ETH and reduced the contents of GAs and IAA, thereby inhibiting the expression of GID1, promoting the expression of GAI, and ultimately inhibiting the internode elongation in sugarcane.