Tea Plants Process Selenite and Selenate Through Distinct Metabolic Pathways

Tea plants supplied with selenite or selenate under hydroponic conditions exhibit distinct metabolic patterns for selenium uptake, transport, and transformation, according to a study published in BMC Plant Biology. To track these dynamics, researchers established an analytical method capable of simultaneously determining five major selenium species in Camellia sinensis: selenite, selenate, selenocystine, methylselenocysteine, and selenomethionine.

The investigation demonstrated contrasting behaviors between the two exogenous selenium sources. When tea plants absorb selenate, the element translocates quickly to above-ground tissues and subsequently converts into organic selenium via a selenite intermediate.

Conversely, selenite supplied to the plants is completely retained within the roots rather than directly moving upward. In the root tissues, the selenite is rapidly transformed into organic selenium species, which are then predominantly transported to the leaves as methylselenocysteine and selenomethionine. The first day following selenite treatment serves as a critical stage for this speciation shift, marked by rapid organic selenium accumulation.

Integrated transcriptome analysis identified significant induction of transport and transformation genes during this critical initial phase. The researchers detected multiple differentially expressed candidate genes across twelve gene families, specifically SULTR, PHT, AQP, NHX, NRT, APS, APR, SIR, CYS, CGS, HMT, and MTR. These expression shifts imply potential functional roles in mediating selenium uptake, translocation, and conversion across the plant.

Based on these findings, the authors proposed a putative molecular model outlining selenium uptake, transport, and transformation in tea plants, while noting that the specific functions of the candidate genes remain to be validated. Because tea plants accumulate selenium and convert inorganic forms into organic compounds, clarifying these pathways provides technical and theoretical foundations for developing selenium-enriched tea production strategies.

Selenium is recognized as an essential micronutrient for humans and serves as a beneficial element for plants. Because tea plants efficiently accumulate selenium and convert inorganic forms into organic selenium species, selenium-enriched tea provides an important dietary source of bioavailable selenium. Nonetheless, the molecular mechanisms underlying selenium uptake, transport, and transformation in tea plants have remained largely unknown. Prior to this investigation, understanding regarding the dynamic conversion process that transforms inorganic selenium into distinct organic selenium species had remained particularly limited.

Subject of Research: Selenium uptake, transport, and transformation in tea plants

Article Title: Se uptake, transport and transformation in tea plants (Camellia sinensis) supplied with selenite or selenate under hydroponic conditions

Article References: Bai, H., Li, M., Lv, X., Yang, C., Huang, H., Liu, J., Qi, Y., Liu, S., Zhou, J., Yu, Y., Zhang, J., & Wang, W. (2026). Se uptake, transport and transformation in tea plants (Camellia sinensis) supplied with selenite or selenate under hydroponic conditions. BMC Plant Biology. https://doi.org/10.1186/s12870-026-10368-1

Image Credits: AI Generated

DOI: 10.1186/s12870-026-10368-1

Keywords: Camellia sinensis, selenium metabolism, selenite, selenate, hydroponics, plant biology, transcriptome analysis, selenium speciation, uptake, transport, transformation, plants