Agrochemicals provide vast potential to improve plant productivity, because they are easy to implement at low cost while not being restricted by species barriers as compared with breeding strategies. Despite the general interest, only a few compounds with growth-promoting activity have been described so far. Here, we add cis-cinnamic acid (c-CA) to the small portfolio of existing plant growth stimulators. When applied at low micromolar concentrations to Arabidopsis roots, c-CA stimulates both cell division and cell expansion in leaves. Our data support a model explaining the increase in shoot biomass as the consequence of a larger root system, which allows the plant to explore larger areas for resources. The requirement of the cis-configuration for the growth-promoting activity of CA was validated by implementing stable structural analogs of both cis- and trans-CA in this study. In a complementary approach, we used specific light conditions to prevent cis/trans-isomerization of CA during the experiment. In both cases, the cis-form stimulated plant growth, whereas the trans-form was inactive. Based on these data, we conclude that c-CA is an appealing lead compound representing a novel class of growth-promoting agrochemicals. Unraveling the underlying molecular mechanism could lead to the development of innovative strategies for boosting plant biomass.

中文翻译：

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顺式肉桂酸是天然的促进植物生长的化合物。

农用化学品具有巨大的潜力，可提高植物的生产率，因为与育种策略相比，它们易于实施且成本低廉，而且不受物种壁垒的限制。尽管有普遍的兴趣，到目前为止，仅描述了少数具有促进生长活性的化合物。在这里，我们将顺式肉桂酸（c -CA）添加到现有植物生长刺激剂的少量组合中。当以低微摩尔浓度施用于拟南芥根时，c -CA刺激叶片中的细胞分裂和细胞扩增。我们的数据支持一个模型，该模型解释了由于较大的根系而导致的芽生物量的增加，这使植物能够探索更大的资源区域。顺式的要求在本研究中，通过实施顺式-和反式-CA的稳定结构类似物，验证了CA促进生长的构型。在一种补充方法中，我们在实验过程中使用了特定的光照条件来防止CA的顺式/反式异构化。在这两种情况下，顺式均能刺激植物生长，而反式则无活性。基于这些数据，我们得出结论，c -CA是一种有吸引力的先导化合物，代表了一类新型的促进生长的农用化学品。弄清潜在的分子机制可能导致开发提高植物生物量的创新策略。