Abstract

CO₂ application is one of the important ways to promote crop growth and increase yield, especially for facility crop cultivation. Since carrot is a widespread vegetable, the area of off-season facility cultivation has been increasing in recent years. Jasmonic acid (JA) is a signal molecule that responds quickly to external stimulation in plants, so it is very important to study the JA metabolism under CO₂ enrichment. In this study, the JA content and the biomass were measured during the growth and development of carrots under natural conditions and CO₂ enrichment in greenhouse. The results showed that the JA content in carrot leaves under CO₂ enrichment was higher than that of the control at all stages except harvest stage, but the leaf biomass and root yield were increased at all stages. RNA sequencing identified 482 differentially expressed genes (DEGs). By analyzing the JA synthesis pathway, five DEGs were obtained. In addition, GO annotation found 21 genes that respond to JA or are related to JA-mediated signal transduction. Among them, seven genes are directly related to growth and development, five genes are related to hormonal regulation, and six genes are related to stress. This study showed that JA was highly responsive to CO₂ enrichment: JA not only regulated carrot growth, but also responded to abiotic stress. This research provides new insights into the process of plants adapting to high levels of CO₂.

摘要

CO ₂施用是促进作物生长和增产的重要途径之一，尤其是设施作物栽培。由于胡萝卜是一种广泛种植的蔬菜，近年来淡季设施种植面积不断增加。茉莉酸(JA)是植物体内对外界刺激反应迅速的信号分子，因此研究CO ₂富集下的JA代谢具有重要意义。在这项研究中，在自然条件下和温室中CO ₂富集的胡萝卜生长和发育过程中测量了JA含量和生物量。结果表明，CO _{2 作用}下胡萝卜叶片中JA含量除收获期外，各阶段富集均高于对照，但各阶段叶片生物量和根产量均有所增加。RNA测序鉴定了482个差异表达基因（DEG）。通过分析JA合成途径，获得了5个DEG。此外，GO注释发现了21个响应JA或与JA介导的信号转导相关的基因。其中，与生长发育直接相关的基因有7个，与激素调节相关的基因有5个，与应激相关的基因有6个。这项研究表明，JA 对 CO ₂富集反应强烈：JA 不仅调节胡萝卜的生长，而且对非生物胁迫做出反应。这项研究为植物适应高浓度 CO ₂的过程提供了新的见解。