Foxtail millet is highly valued in China; however, its optimal fertilization parameters are unknown. This study investigated the effects of nitrogen (N), phosphorus (P), and potassium (K) fertilizer combinations on foxtail millet agronomic traits, photosynthetic characteristics, yield, and quality to promote rational fertilizer application. Pot experiments were conducted using the “3414” fertilizer effect scheme and the representative crop variety was JG21, containing four NPK levels and 20 replicates per treatment, individually. The effects of N, P, and K levels on agronomic traits were analyzed during the jointing, heading, and filling stages. JG21 performed optimally under treatment with N₁₆₀P₉₀K₁₅₀ (T₆); the yield and fat content increased by 49.32% and 13% compared to the control. Correlation analysis revealed that N was significantly positively (negatively) correlated with the protein (amylose) content. P was significantly positively correlated with the fat and moisture content and K was correlated with the moisture, fat, and protein content, but was negatively with the amylose content. Overall, rational ratios of NPK fertilization improved foxtail millet yield and quality. Based on fuzzy comprehensive evaluation, the T₆ treatment (N₁₆₀P₉₀K₁₅₀) demonstrated the highest comprehensive effect among 13 NPK fertilizer combinations. Rational application of NPK in foxtail millet may improve agronomic performance by enhancing leaf photosynthetic efficiency and aboveground biomass accumulation.

Background: Acyl-CoA-Binding proteins (ACBPs) function as coenzyme A transporters and play important roles in regulating plant growth and development in response to abiotic stress and phytohormones, as well as in membrane repair. To date, the ACBP family has not been a comprehensively characterized in barley (Hordeum vulgare L.). Results: Eight ACBP genes were identified in the barley genome and named as HvACBP1–8. The analysis of the proteins structure and promoter elements of HvACBP suggested its potential functions in plant growth, development, and stress response. These HvACBPs are expressed in specific tissues and organs following induction by abiotic stressors such as drought, salinity, UV-B exposure, temperature extremes, and exposure to exogenous phytohormones. The HvACBP7 and HvACBP8 amino acid sequences were conserved during the domestication of Tibetan Qingke barley. Conclusions: Acyl-CoA-binding proteins may play important roles in barley growth and environmental adaptation. This study provides foundation for further analyses of the biological functions of HvACBPs in the barley stress response.

Enhancing the absorption and utilization of phosphorus by crops is an important aim for ensuring food security worldwide. However, the gene regulatory network underlying phosphorus use in foxtail millet remains unclear. In this study, the molecular mechanism underlying low-phosphorus (LP) responsiveness in foxtail millet was evaluated using a comparative transcriptome analysis. LP reduced the chlorophyll content in shoots, increased the anthocyanin content in roots, and up-regulated purple acid phosphatase and phytase activities as well as antioxidant systems (CAT, POD, and SOD). Finally, 13 differentially expressed genes related to LP response were identified and verified using transcriptomic data and qRT-PCR. Two gene co-expression network modules related to phosphorus responsiveness were positively correlated with POD, CAT, and PAPs. Of these, SiPHR1, functionally annotated as PHOSPHATE STARVATION RESPONSE 1, was identified as an MYB transcription factor related to phosphate responsiveness. SiPHR1 overexpression in Arabidopsis significantly modified the root architecture. LP stress caused cellular, physiological, and phenotypic changes in seedlings. SiPHR1 functioned as a positive regulator by activating downstream genes related to LP tolerance. These results improve our understanding of the molecular mechanism underlying responsiveness to LP stress, thereby laying a theoretical foundation for the genetic modification and breeding of new LP-tolerant foxtail millet varieties.

Mechanized harvesting is a crucial step in the agricultural production of foxtail millet (Setaria italica), as its peduncles are susceptible to bending and breaking during the harvesting process, leading to yield losses and deterioration in grain quality. To evaluate the suitability of foxtail millet for mechanical harvesting, this study comprehensively analyzed the biomechanical properties of the peduncles and related biological morphological characteristics of 116 foxtail millet accessions, establishing a system for indicator screening and comprehensive evaluation. Using partial correlation analysis and R-type cluster analysis, four biomechanical and seven related morphological indices of the peduncle were screened from 22 candidate indicators, with their coefficient of variation ranging from 6% to 80%. The entropy method was used to assign weights to the selected indices, with biomechanical factors contributing 47.4%, peduncle morphology 20.2%, spike morphology 27.6%, and plant height 4.8%. The Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) and Rank-Sum Ratio (RSR) methods were applied to rank and grade the classification of the 116 foxtail millet varieties into four performance groups: Excellent (8 varieties), Good (50 varieties), Moderate (51 varieties), and Poor (7 varieties). This study provides a scientific basis for the selection and evaluation of foxtail millet varieties.

Background Acyl-CoA-binding proteins (ACBPs), which are coenzyme A transporters, play important roles in regulating plant growth and development in response to abiotic stress and phytohormones, and in membrane repair. To date, there has not been a comprehensive characterization of the barley (Hordeum vulgare L.) ACBP family. Results Eight ACBP genes were identified in the barley genome named HvACBP1–8. These HvACBP genes are specifically expressed in certain tissues and organs, and their expression is induced by abiotic stressors, such as drought, salinity, UV-B exposure, temperature extremes, and exposure to exogenous phytohormones. The HvACBP7 and HvACBP8 amino acid sequences were still conserved during the domestication of Tibetan Qingke barley. Conclusions These findings suggest that acyl-CoA-binding proteins could play important in barley growth and environmental adaptation. This study lays the foundation for further analyses of the biological functions of HvACBPs in the barley stress response.