State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China.
Protoplasma. 2019 May;256(3):777-788. doi: 10.1007/s00709-018-01341-3. Epub 2019 Jan 2.
Gibberellin (GA) is a phytohormone of a biguanide compound that plays an important role throughout the life cycle of a plant. Lignin, a phenylalanine-derived aromatic polymer, can enhance the water transport function and structural resistance of cell walls. This function is also the core on biology of higher terrestrial plants. An appropriate lignin level is important to the quality of leafy vegetables, such as celery. The relationship between gibberellin levels and the occurrence of lignification has not been reported in celery. In this study, the leaf blades and petioles of celery cultivars 'Liuhe Huangxinqin' and 'Jinnan Shiqin' were used as materials, and different concentrations of exogenous gibberellin were applied to analyze the growth and lignin distribution of leaf blades and petioles. It was found that gibberellin treatment could influence the lignin content in celery leaves. Autofluorescence analysis under ultraviolet (UV) excitation showed that gibberellin treatment caused lignification of celery leaf tissue. The expression profiles of 12 genes related to lignin synthesis changed with the increase of gibberellin concentration. Our results showed that gibberellin played a significant role in the accumulation of lignin in the development of celery leaves. This provides a basis for further study on the regulation of lignin metabolism in plants and exerts a vital part in the application of plant growth regulators to production.
赤霉素（GA）是一种双胍化合物的植物激素，在植物的整个生命周期中都起着重要作用。木质素是一种苯丙氨酸衍生的芳香聚合物，可增强细胞壁的水输送功能和结构抗性。这一功能也是高等陆地植物生物学的核心。适当的木质素水平对芹菜等叶菜类蔬菜的品质很重要。GA 水平与木质化发生之间的关系在芹菜中尚未报道。在这项研究中，以芹菜品种‘六合黄心芹’和‘津南实芹’的叶片和叶柄为材料，施加不同浓度的外源赤霉素，分析叶片和叶柄的生长和木质素分布。结果发现，赤霉素处理会影响芹菜叶片中的木质素含量。紫外（UV）激发下的自发荧光分析表明，赤霉素处理导致芹菜叶片组织木质化。12 个与木质素合成相关的基因的表达谱随赤霉素浓度的增加而变化。我们的结果表明，GA 在芹菜叶片发育过程中木质素的积累中起重要作用。这为进一步研究植物木质素代谢的调控提供了依据，并在植物生长调节剂在生产中的应用中发挥了重要作用。
