Identification of candidate genes associated with JA under elevated CO₂ in carrot (Daucus carota L.)

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.

Keywords:

• CO₂ enrichment
• carrot
• Jasmonic acid
• gene

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by Shanxi Province Key Research and Development Program Key Projects [grant No. 201903D211011-03]; Science and Technology Innovation Fund Project of Shanxi Agricultural University [grant No. 2016ZZ13 and 2005042]; Applied Basic Research Project of Shanxi Province [grant No. 201801D221295].