Background: Ammonium nitrogen (NH₄⁺) serves as a vital nitrogen source, playing pivotal regulatory roles in plant growth, development, and high-yield formation. Ammonium transporters (AMTs), encoded by the AMT gene family, are central to NH₄⁺ transport. However, the functional roles of AMT genes in wheat remain poorly understood. Methods: A comprehensive genome-wide analysis of the TaAMT gene family numbers was conducted, encompassing investigations into gene structure, protein motif composition, gene duplication events, collinearity relationships, and cis-acting regulatory elements. Furthermore, the expression patterns of distinct TaAMT members were examined under varying ammonium supply conditions and pathogen stress. Results: In this study, a total of 21 TaAMT members were identified. Additionally, all TaAMT proteins were localized to the plasma membrane. Phylogenetic analysis clustered these genes into four distinct subgroups. Comparative analyses of gene structure and conserved motifs revealed conserved domain composition and motif organization within each subgroup. Interspecific synteny analysis highlighted evolutionary conservation across species. Promoter region analysis identified multiple cis-regulatory elements associated with hormone signaling, light responsiveness, and abiotic stress adaptation. Expression profiling demonstrated that TaAMT members exhibit both tissue-specific and constitutive expression patterns across developmental stages. RT-qPCR further revealed that the expression of TaAMT members responds to varying concentrations of ammonium nitrogen supply, as well as infection stresses caused by stripe rust and powdery mildew. Conclusions: Collectively, this study uncovered the functional diversity of TaAMT members, offering novel molecular targets and theoretical foundations for breeding wheat varieties with enhanced nitrogen use efficiency and disease resistance.

Background: Ammonium nitrogen (NH₄⁺) serves as a vital nitrogen source, playing pivotal regulatory roles in plant growth, development, and high-yield formation. Ammonium transporters (AMTs), encoded by the AMT gene family, are central to NH4+ transport. However, the functional roles of AMT genes in wheat remain poorly understood.Methods: In this study, a total of 21 TaAMT members were identified. A comprehensive genome-wide analysis was conducted, encompassing investigations into gene structure, protein motif composition, gene duplication events, collinearity relationships, and cis-acting regulatory elements. Furthermore, the expression patterns of distinct TaAMT members were examined under varying ammonium supply conditions and pathogen stress. Results: All TaAMT proteins exhibited hydrophobic characteristics and localized to the plasma membrane. Phylogenetic analysis clustered these genes into four distinct subgroups. Comparative analyses of gene structure and conserved motifs revealed conserved domain composition and motif organization within each subgroup. Interspecific synteny analysis highlighted evolutionary conservation across species. Promoter region analysis identified multiple cis-regulatory elements associated with hormone signaling, light responsiveness, and abiotic stress adaptation. Expression profiling demonstrated that TaAMT members exhibit both tissue-specific and constitutive expression patterns across developmental stages. RT-qPCR further revealed that the expression of TaAMT members responds to varying concentrations of ammonium nitrogen supply, as well as infection stresses caused by stripe rust and powdery mildew. Conclusions: Collectively, this study provides the useful molecular information into the roles of TaAMT members in nitrogen use efficiency and disease resistance, offering valuable genetic resources for wheat breeding programs aimed at enhancing agronomic traits.

Carotenoid content is a key trait that defines the unique characteristics of foxtail millet varieties. Varieties with different levels of carotenoids often show distinct genetic features and nutritional profiles. However, the genetic basis of carotenoid content in foxtail millet remains mostly unknown. In this study, we explored the genetic basis of carotenoid content using a recombinant inbred line (RIL) population of 305 lines derived from two parental accessions, JG21 (high-carotenoid, 16.75 mg·kg⁻¹) and JG25 (low-carotenoid, 0.93 mg·kg⁻¹). The results showed that the RIL population exhibited continuous phenotypic variation and significant transgressive segregation for carotenoid components (lutein, zeaxanthin, β-cryptoxanthin) and kernel color (measured by b* value), with zeaxanthin reaching 8.47 mg·kg⁻¹, significantly surpassing the higher parent (3.44 mg·kg⁻¹) in 24DY. To ensure that enhancing this nutritional trait does not compromise grain yield, we analyzed its relationship with key agronomic traits, testing for pleiotropic trade-offs. Notably, carotenoid content showed no significant correlation with any of the 8 key agronomic traits (r ranged from −0.11 to 0.08, all p > 0.05), suggesting no apparent trade-off, although fine-mapping is needed to separate pleiotropy from tight linkage for concurrent improvement. Genetic modeling analysis revealed that carotenoid content is stably controlled by three major-gene pairs plus polygenes (MX3-AI-A model), with major-gene heritability of 96.65% and polygene heritability of 3.35%. Based on this framework, three elite RILs with >23% higher carotenoid and superior agronomic performance were identified and advanced to marker-assisted backcrossing. These results provide a clear genetic framework and immediate breeding resources for marker-assisted selection, enabling the development of high-yielding, carotenoid-enriched foxtail millet varieties without compromising agronomic value.

Background: Anthocyanin accumulation is a developmentally regulated trait shaped by complex interactions between metabolic and transcriptional networks. However, dissecting the regulatory mechanisms underlying anthocyanin biosynthesis is often complicated by confounding variation in plant growth and environmental conditions. Methods: Here, we used a time-resolved multi-omics approach to investigate anthocyanin accumulation in maize seedlings by comparing an anthocyanin-rich inbred line PH19401 with an anthocyanin-deficient line YPX across five developmental stages. Results: Untargeted metabolomic and transcriptomic profiling revealed progressive divergence between the two lines beginning at early development stages. Using a dual-line, intersection-based filtering strategy, we identified a refined set of metabolites and genes closely associated with anthocyanin accumulation. These candidates were enriched in pathways related to phenylpropanoid metabolism, energy metabolism, and redox regulation. Weighted gene co-expression network analysis (WGCNA) identified two transcriptional modules that showed opposing associations with anthocyanin content. The positively associated module was centered on MYB transcription factors, consistent with canonical regulation of flavonoid biosynthesis, whereas the negatively associated module was enriched in genes involved in primary metabolism and signaling. Integration of transcriptomic and metabolomic datasets further revealed coordinated relationships between MYB hub genes and flavonoid intermediates, linking transcriptional regulation with metabolic output. Together, these results support a model in which anthocyanin accumulation is associated with activation of MYB-centered transcriptional programs and broader metabolic reprogramming that enhances precursor supply and redox balance, while competing transcriptional programs favor primary metabolism. Conclusions: This study provides a systems-level perspective on anthocyanin biosynthesis in maize seedlings and establishes an analytical framework for dissecting developmentally regulated metabolic traits.

The ABCB subfamily, a subset transporter of the ATP-binding cassette (ABC) superfamily, is vital for various plant life processes, especially in the transport of polar auxin and brassinosteroids. Although ABCB transporters have been characterized in diverse plant species, their specific functions in wheat remain largely unexplored. In this study, we identified 99 TaABCB members in wheat and categorized them into four groups based on their conserved domains and phylogenetic relationships. These members were found to be unevenly distributed across all 21 wheat chromosomes. We conducted a comprehensive genome-wide analysis encompassing gene structure, protein motifs, gene duplication events, collinearity, and cis-acting elements. Transcriptome analysis revealed that different TaABCB members displayed distinct expression patterns under phosphate starvation stress. Notably, we discovered that TaABCB7 might play a role in regulating wheat’s phosphate starvation. Crucially, we pinpointed an elite haplotype, H001, of the candidate gene TaABCB7, which has been progressively selected and employed in wheat breeding improvement programs. Overall, this study enhances our comprehensive understanding of TaABCB members and offers a potential gene resource for molecular marker-assisted selection breeding in wheat.