Rapid Screening of Maize Inbred Lines Based on NIR-MIR Spectral Characteristics and Small-molecule Metabolites

Near-infrared (NIR), Mid-infrared (MIR) spectroscopy and Gas chromatography -mass spectrometry (GC-MS) combined with principal component analysis (PCA) were used to preliminarily select suitable maize parents that can be further employed in future breeding process. Especially, a new matrix was innovatively developed in terms of metabolic components, and used for PCA. Firstly, the quality maize seeds were selected based on the score plots from PCA of NIR, MIR, fusion of NIR and MIR, and GC-MS. Then, the potential biomarkers, including phenol, propionic acid, DL-malic acid, L-valine, which have great influence on the selection of quality maize seeds, were confirmed based on the loading plots from PCA of GC-MS and MIR spectral data. Finally, the quantitative analysis of partial biomarkers for selected parents was carried based on GC-MS method. The selected suitable maize parents were further confirmed by the difference of biomarkers contents. The results showed that NIR, MIR, and GC-MS combined with PCA are as rapid, convenient analysis methods, and can be thus employed for future maize breeding process.