Can Plants Absorb and Transform Chemicals from Other Plants?
"Unveiling the surprising phenomenon of horizontal natural product transfer and its implications for plant health and environmental science."
Plants are constantly exposed to a cocktail of chemicals in their environment, many of which originate from human activities. These compounds, known as xenobiotics, can be absorbed by plants through their roots or leaves and then translocated throughout their tissues. For a long time, research focused mainly on these human-made chemicals, but recently, scientists have discovered that plants also take up natural products from other plants.
This phenomenon, called "horizontal natural product transfer," occurs when natural compounds are released from decaying plant material and then absorbed by nearby living plants. This raises fascinating questions about how plants interact with their environment and whether they can modify these borrowed compounds to their benefit.
To investigate this further, researchers studied the uptake and modification of a specific natural compound, umbelliferone, in various plant seedlings. Umbelliferone, a type of coumarin, is easily detectable and served as a model to explore the broader implications of horizontal natural product transfer.
Horizontal Gene Transfer in Plants
Horizontal gene transfer (HGT) is the interspecific transmission of genetic information across reproductive barriers, distinct from the vertical inheritance that occurs through reproduction. A 2021 review reports that HGT has been documented widely in nature, including in plants. A 2026 article describes quantifying the proportion of plant genes predicted to derive from prokaryotes since the streptophyte ancestor, but the provided material gives no numerical result.
Evidence and Open Questions
Research on interkingdom horizontal gene transfer in plants has accumulated over the past decade, but its prevalence in eukaryotes—particularly multicellular organisms—remains actively discussed. A 2026 review describes sequence-based and phylogenomic approaches for identifying putative HGT and testing the robustness of those claims. The supplied sources do not establish one definitive method or settle the debate over how common these transfers are.
How Plants Absorb and Change Umbelliferone
The study involved growing seedlings of barley, radish, pea, flax, and garden cress in hydroponic solutions containing umbelliferone. After a week, the researchers analyzed the plant tissues to see if umbelliferone had been absorbed. The results were striking: all five plant species had taken up significant amounts of umbelliferone.
- Uptake Confirmation: HPLC analyses confirmed that umbelliferone was absorbed into the aerial parts of all seedlings.
- Modification in Specific Plants: Garden cress hydroxylated and glucosylated umbelliferone to esculin, while barley seedlings methoxylated it to scopoletin.
- Enzyme Involvement: Cytochrome P450 enzymes, known for modifying xenobiotics, are likely responsible for these transformations.
Chemical Processing and Gene Transfer
A wheat metabolomics study reports that exposure to the green leaf volatile Z-3-hexenyl acetate is associated with ROS production and glycosylation events. The source explains that glycosylated compounds can be transported to and stored in vacuoles, then released under stress or cellular damage and converted to active aglycons by glucosidases in different cell organelles. Separately, a 2026 review reports that microbe-to-plant HGT occurs across major plant groups and appears frequent in charophytes and bryophytes; acquired microbial genes have contributed to major physiological and structural innovations in land plants.
Limits of Allelopathy Evidence
A critical reassessment notes that experiments have shown phytochemicals can affect the growth and development of plants and microbes. However, such experiments are usually conducted in controlled laboratory or glasshouse conditions, excluding many biological processes that shape natural systems. A separate review notes that plants taking up xenobiotics from soil can frequently modify them within the receiving plant, complicating assumptions about the effects of transferred chemicals.
Gene Transfer and Chemical Bioaccumulation
A comparative genomics survey of five parasitic plants and their hosts estimated that 0.1–0.2% of genes in obligate parasitic plants originated through HGT from their hosts. In a separate review of chemical uptake, researchers compiled 7,049 measured bioaccumulation entries covering 310 organic chemicals and 112 terrestrial plant species. These figures describe different phenomena—gene transfer and chemical bioaccumulation—and should not be treated as directly comparable measures.
What This Means for Plant Science and Ecology
This study demonstrates that plants can absorb and modify phenolic compounds from their environment, expanding our understanding of horizontal natural product transfer. This phenomenon likely plays a more significant role in plant ecology than previously thought, influencing how plants interact with each other and their surroundings. Further research is needed to explore the full extent of this process and its implications for plant health and ecosystem dynamics.
HGT and Plant Adaptation
Horizontal gene transfer is the movement of genetic material between distinct species by means other than sexual reproduction. The review reports that HGT has contributed substantially to genome plasticity and adaptive evolution in prokaryotes and certain unicellular eukaryotes. It frames the evolution of green plants—from chlorophyte algae to angiosperms and from water to land—as a context for considering plant adaptation, but the supplied excerpt gives no specific human or practical impact.