Long-term preservation strategy for legume root nodule phenotypes coupled with a comprehensive evaluation method.
Ya Zhao1,2,3, Can Guo2, Wen Zhang2
1College of Engineering, China Agricultural University, Beijing, 100083, China.
BMC Plant Biology
|May 22, 2026
Summary
A new two-stage aqueous-phase preservation method (TAPP) effectively preserves legume root nodule morphology and color for long-term studies. This standardized workflow supports cross-regional phenomics and comparability of nodule phenotypes.
Area of Science:
- Agricultural Science
- Plant Biology
- Microbiology
Background:
- Legume nodule color and morphology are crucial indicators of symbiotic performance.
- Preserving these features post-excavation for long-term analysis is challenging due to degradation.
- Oxidation and dehydration sensitivity complicate nodule phenotyping.
Purpose of the Study:
- To develop and evaluate a novel preservation method for legume root nodules.
- To establish a standardized workflow for long-term nodule phenotyping.
- To enable cross-regional and collaborative studies on legume symbiosis.
Main Methods:
- Developed a two-stage aqueous-phase preservation method (TAPP).
- Evaluated preservation using composite morphological scores, color difference (ΔE), and contamination grades.
- Compared TAPP with FormalinCu, TAPP-Resin, Resin, and AirDry methods over 24 months.
Main Results:
- TAPP demonstrated superior preservation of nodule morphology and color compared to other methods.
- TAPP-preserved nodules showed minimal degradation, with high morphological scores (4.65/4.63) at 24 months.
- Color change in TAPP samples slowed significantly over time, indicating effective stabilization.
Conclusions:
- The TAPP method provides a reliable solution for long-term preservation of legume root nodules.
- The proposed workflow facilitates standardized, traceable phenotyping for research.
- This advancement supports improved comparability and collaborative analysis in legume symbiosis research.
