stable-isotope-tracing
Stable-isotope tracing is a technique that uses non-radioactive heavy isotopes (such as ¹³C, ¹⁵N, or ²H) as molecular labels to track the movement and transformation of compounds through metabolic pathways. In plant science, it allows researchers to map nutrient uptake, carbon fixation, and the flow of metabolites through photosynthesis, respiration, and secondary metabolism with high precision. This approach has been particularly valuable for understanding how plants allocate resources, form symbiotic relationships, and respond to environmental stresses at the biochemical level.
open_in_new WikipediaPubMed · 2026-04-29
Researchers used stable isotope analysis of phenylalanine — a specific amino acid — to detect how much carbon green plants secretly steal from their fungal partners underground. Standard bulk isotope methods weren't sensitive enough to catch this theft in orchids and arbuscular mycorrhizal plants, but tracking phenylalanine revealed hidden fungal-derived nutrition that was previously invisible.
Bulk stable isotope analysis is insufficient to detect fungal-derived carbon acquisition in arbuscular mycorrhizal plants and rhizoctonia-associated orchids
Compound-specific isotope analysis of phenylalanine provides higher resolution detection of fungal carbon transfer to green plants
Partial mycoheterotrophy (fungal carbon theft) may be more widespread among green plants than previously measurable with standard methods
