Jafari, ASeth, KWerner, AShi, SHofmann, RHoyos-Villegas, V2024-11-202024-07-302024-11-202024-082024-07-271424-822039123990 (pubmed)https://hdl.handle.net/10182/17845Biological nitrogen fixation (BNF) by symbiotic bacteria plays a vital role in sustainable agriculture. However, current quantification methods are often expensive and impractical. This study explores the potential of Raman spectroscopy, a non-invasive technique, for rapid assessment of BNF activity in soybeans. Raman spectra were obtained from soybean plants grown with and without rhizobia bacteria to identify spectral signatures associated with BNF. δN¹⁵ isotope ratio mass spectrometry (IRMS) was used to determine actual BNF percentages. Partial least squares regression (PLSR) was employed to develop a model for BNF quantification based on Raman spectra. The model explained 80% of the variation in BNF activity. To enhance the model’s specificity for BNF detection regardless of nitrogen availability, a subsequent elastic net (Enet) regularisation strategy was implemented. This approach provided insights into key wavenumbers and biochemicals associated with BNF in soybeans.14 pagesElectronicen© 2024 by the authors. Licensee MDPI, Basel, Switzerland.biosystemschemometricsnon-destructivepattern recognitionprecision agriculturerhizobiasymbiosisFabaceaeNitrogenSpectrum Analysis, RamanLeast-Squares AnalysisNitrogen FixationSymbiosisGlycine maxJournal Article10.3390/s241549441424-8220ANZSRC::300210 Sustainable agricultural developmentANZSRC::460907 Information systems for sustainable development and the public goodANZSRC::410603 Soil biologyANZSRC::300805 Oenology and viticultureANZSRC::4008 Electrical engineeringANZSRC::4009 Electronics, sensors and digital hardwareANZSRC::4606 Distributed computing and systems softwarehttps://creativecommons.org/licenses/by/4.0/Attribution