The Surprising Link Between Tea Quality and Root Bacteria

The type of tea used to make a fine cup of tea will significantly impact its flavor. However, a study published in the journal Current Biology reveals that the collection of bacteria found on tea roots is another essential component needed to make a great cup of tea.

The researchers demonstrated that they could improve on high-quality tea by making changes to that assembly.

Significant disparities in microbial communities, particularly nitrogen metabolism-related microorganisms, were identified in the roots of tea plants with varying qualities through microbiomics, crucially, through the isolation and assembly of a synthetic microbial community from high-quality tea plant roots, we managed to notably enhance the amino acid content in various tea plant varieties, resulting in an improvement in tea quality.”

Tongda Xu, Study Corresponding Author, Fujian Agriculture and Forestry University

An abundance of genetic resources for cultivating tea plants can be found in China. However, the researchers clarify that it is difficult to enhance the quality of tea using molecular genetic breeding techniques. There is interest in exploring further tea-enhancing and modifying techniques, such as utilizing microbiological agents.

Previous research has demonstrated that soil microorganisms residing in plant roots have an impact on how nutrients are absorbed and utilized by plants. The goal of the current study was to find out more about the precise role that root microorganisms play in tea quality.

Next, they created a synthetic microbial community called SynCom, which was remarkably similar to the one discovered in connection with the Rougui tea type, which has a high theanine content. They discovered that applying SynCom to tea roots increased theanine levels.

Additionally, the bacteria improved the ability of Arabidopsis thaliana, a plant frequently employed in fundamental biological research, to withstand low nitrogen environments.

The initial expectation for the synthetic microbial community derived from high-quality tea plant roots was to enhance the quality of low-quality tea plants, however, to our astonishment, we discovered that the synthetic microbial community not only enhances the quality of low-quality tea plants but also exerts a significant promoting effect on certain high-quality tea varieties. Furthermore, this effect is particularly pronounced in low-nitrogen soil conditions.”

Wenxin Tang, Study Co-Author, Fujian Agriculture and Forestry University

According to the research, artificially created microbial communities may enhance teas, particularly when planted in soil lacking nitrogen. The finding may contribute to a decrease in the usage of chemical fertilizers while improving the quality of tea trees, as tea trees have a high nitrogen requirement. The results could have significant effects on crops used in agriculture more generally.

Based on our current experimental findings, the inclusion of the SynCom21 microbial community has not only improved the absorption of ammonium nitrogen in different tea varieties but also enhanced the uptake of ammonium nitrogen in Arabidopsis thaliana, and this suggests that the ammonium nitrogen uptake-promoting function of SynCom21 may be applicable to various plants, including other crops.”

Tongda Xu, Study Corresponding Author, Fujian Agriculture and Forestry University

They claim, for example, that it might make it possible to cultivate rice with better characteristics, including a higher protein content. They now intend to evaluate SynCom's application in field trials and enhance it even more.

They also want to find out more about the various secondary metabolites in tea trees and how they are impacted by root microorganisms.