A water-soluble polysaccharide from foxtail millet (FM-D1) was isolated and purified through gradient ethanol precipitation and column chromatography. Size-Exclusion Chromatography–Multi-Angle Light Scattering–Refractive Index (SEC-MALLS-RI) and high-performance anion-exchange chromatography (HPAEC) analyses revealed that FM-D1 constitutes a highly purified neutral polysaccharide exclusively composed of glucose as the sugar unit, with a molecular weight of 14.823 kDa. The structural characterization results obtained from gas chromatography–mass spectrometer (GC–MS) and nuclear magnetic resonance spectroscopy (NMR) spectra suggest that FM-D1 primarily consists of a main chain linked by →4)-α-D-Glcp-(1→ and minor quantities of →4,6)-α-D-Glcp-(1→ to form the main chain, with branching mainly composed of α-D-Glcp-(1→ attached to the O-6 position of →4,6)-α-D-Glcp-(1→ sugar residues. Based on these findings, the antioxidant and immunomodulatory activities of FM-D1 were evaluated in vitro. The results indicated that FM-D1 exhibited moderate 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-Azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) radical scavenging capacity and total antioxidant capacity (TAOC). Furthermore, FM-D1 stimulated macrophage proliferation and inhibited the production of nitric oxide (NO) and inflammatory factors (TNF-α, IL-1β, and IL-6) in lipopolysaccharide (LPS)-stimulated RAW 246.7 cells. Overall, the findings of this study suggest that foxtail millet holds promise as a potential antioxidant agent and immunologic substance in functional foods.

Genotype by environment interaction (GEI) is a major limiting factor in the regional planting and breeding of cultivars. The objective of this study was to assess GEI for grain yield in foxtail millet cultivars grown in northwest China and identify promising genotypes and representative seed production environments. The study used 12 genotypes in eight environments, representative of early-maturing growing areas. Additive main effects and multiplicative interaction (AMMI) and genotype and genotype by environment (GGE) biplot analysis were used to analyze the data. AMMI analysis of variance (ANOVA) indicated that genotype (G), environment (E), and GEI had significant effects (p < 0.01). The E contributed the highest percentage of the total sum of squares (SS) (43.4%), followed by G×E (28.6%) and G (19.5%). Six stability parameters based on AMMI were used to analyze yielding stability. YG35, FH9, DT29, and ZZG21 were more stable. The correlation coefficients between the six parameters were > 0.8. The genomic selection index (GSI) was then used to identify the stable and high-yield genotypes (YG35, ZZG21, and DT29). GGE biplot analysis revealed the same cultivars as the best performers for being closest to the ideal cultivar. The test sites were classified into two mega-environments using GGE biplot analysis for genotype assessment and seed production. CF and XJ were identified as the closest to the ideal test site, with relatively strong discriminatory ability and representativeness. Therefore, the findings of this study provide insights for the regional planting and breeding of foxtail millet in the future.

With the ubiquity of lithium‐ion batteries, lithium has emerged as a critical environmental contaminant, yet the mechanisms of its toxicity and tolerance in plants remain poorly understood. This study investigates the physiological and molecular responses of the C4 model crop foxtail millet ( Setaria italica ) to LiCl stress. Physiological analyses revealed a concentration‐dependent effect: while low Li ⁺ levels activated the antioxidant system, exposure to 50 mg/L LiCl triggered a severe oxidative burst, leading to the suppression of antioxidant enzyme activities (SOD, POD, CAT), lipid peroxidation, and significant growth inhibition. Transcriptomic profiling of the cultivar “Jingu 21” identified 1562 commonly regulated differentially expressed genes, indicating that Li ⁺ stress disrupts Na ⁺ /K ⁺ homeostasis and reprograms metabolic pathways, including the upregulation of branched‐chain amino acid degradation and plant‐pathogen interaction pathways. To validate these findings, we analyzed five additional cultivars exhibiting differential tolerance. Comparative analysis demonstrated that the robust tolerance observed in “Jigu 22” correlated with the strong induction of key genes‐specifically the transcription factor SiBHLH148 , the vacuolar transporter SiNHX1 , and the lipid transfer protein SiDIR1 ‐ suggesting their pivotal roles in maintaining ROS homeostasis and ion compartmentalization. These results elucidate the molecular basis of LiCl adaptation in foxtail millet and provide crucial genetic targets for breeding crops resilient to lithium pollution.

Thousand‐grain weight (TGW) is a critical determinant of grain yield in foxtail millet. To elucidate the molecular regulatory network governing this trait, we systematically evaluated the main agronomic traits and genetic diversity of 40 core germplasm accessions, aiming to identify elite genetic resources. Subsequently, transcriptomic differential expression analysis, weighted gene co‐expression network analysis (WGCNA), pathway enrichment analysis, and inter‐pathway interaction network analysis were performed on materials with contrasting TGW (high vs. low), with the goal of pinpointing key candidate genes involved in TGW regulation. The phenotypic analysis results indicated that the Shannon‐Wiener diversity index (H′) of eight agronomic traits ranged from 1.82 to 2.04, and the coefficients of variation (CV) ranged from 21.83% to 68.14%. Genetic parameter analysis indicated that TGW exhibited the highest broad‐sense heritability (87.10%). The GE variance components were significant for all traits ( p < 0.05). Meanwhile, for TGW, plant height (PH), and panicle length (PL), these components were significantly smaller than the genotypic variances, except for SW and PD. Cluster analysis classified the 40 germplasm accessions into four groups. Group III exhibited superior overall performance, particularly for TGW, highlighting its application potential in high‐yield breeding. Principal component analysis (PCA) extracted four principal components, explaining 84.97% of the total variation. Correlation analysis revealed a highly significant positive association between TGW and both GWMP and panicle weight per main stem (PWMS). Transcriptomic data revealed that pathways related to carbohydrate metabolism, sugar transport, starch biosynthesis, and cell wall formation were significantly enhanced in high‐TGW materials, collectively constituting the core regulatory network for TGW formation. Through integrative analysis of multiple datasets, the cell wall invertase gene CIN1 was identified as a key candidate gene, whose expression level showed a significant positive correlation with TGW. Furthermore, the transcription factor WRKY50 was predicted to regulate CIN1 , potentially contributing to TGW determination in foxtail millet. These findings provide candidate genes and a theoretical basis for molecular breeding and the discovery of yield‐related genes in foxtail millet.