Search Results (14)

Within the framework of organic acid alternatives to chemical herbicides, pre-emergence weed control research is scarce. Citric acid (CA) and lactic acid (LA), considered significantly less effective than pelargonic acid (PA) and acetic acid (AA) from post-emergence (foliar spraying) studies, have largely been disregarded. This in vitro study was aimed at comparing the effects of 5–20% AA, AA + essential oils, PA, CA, and LA on radicle emergence inhibition (direct spraying of seeds) and shoot emergence inhibition (application to peat) on both weeds (perennial ryegrass, green foxtail, common vetch and chicory) and crops (soft wheat, alfalfa and millet). All tested compounds demonstrated concentration-dependent and species-specific effects on shoot emergence inhibition, with CA and LA (IC₅₀ range: 3.4–19.3%) showing a comparable efficacy to PA and AA (IC₅₀ range: 3.1–35.9%). The results also showed that CA and, to a lesser extent, LA were less inhibitory to soft wheat (CA IC₅₀ = 62.5%; LA IC₅₀ = 35.9%) and alfalfa (CA IC₅₀ = 57.8%; LA IC₅₀ = 44.1%) shoot emergence. CA and LA show potential promise for pre-emergence weed control in field testing, either on a stale seedbed in pre-crop sowing or concurrently with soft wheat and alfalfa sowing. Investigating organic compound herbicidal effects on crops of interest warrants attention. Full article

The Short Internodes-Related Sequence (SRS) family, a class of plant-specific transcription factors crucial for diverse biological processes, was systematically investigated in foxtail millet using pan-genome data from 110 core germplasm resources as well as two high-quality genomes (xm and Yu1). We identified SRS members and analyzed their intra-species distribution patterns, including copy number variation (CNV) and interchromosomal translocations. A novel standardized nomenclature (Accession_SiSRSN[.n]_xDy or xTy) was proposed to unify gene family nomenclature, enabling the direct visualization of member number variation across germplasms and the identification of core/variable members while highlighting chromosomal translocations. Focusing on the two high-quality genomes, both harboring six core SRS members, we performed whole-genome collinearity analysis with Arabidopsis, rice, maize, soybean, and green foxtail. Ka/Ks analysis of collinear gene pairs revealed purifying selection acting on SiSRS genes. Promoter analysis identified abundant stress-responsive cis-elements. Among core members, the xm_SiSRS5 gene exhibited the highest expression during vegetative growth but showed significant downregulation under drought and salt stress, suggesting its role as a key negative regulator in abiotic stress responses. This study demonstrates the utility of pan-genomics in resolving gene family dynamics and establishes SiSRS5 as a critical target for stress tolerance engineering in foxtail millet. Full article

Background: Foxtail millet (Setaria italica), domesticated from green foxtail (Setaria viridis), is crucial for global food security. Given increasing environmental challenges, exploring its stress-resistance mechanisms via researching the BREVIS RADIX (BRX) gene family is urgent. Methods: The study combines advanced bioinformatics and experimental validation. It uses phylogenetic, motif, domain, synteny analyses, miRNA prediction, and quantitative expression profiling under stress. Results: Phylogenetic analysis reveals new sub-clades and trajectories. Motif and domain analyses find new conserved elements. Statistical models show unique selective forces. Synteny analysis identifies genomic architecture and new blocks. miRNA prediction reveals gene-miRNA interactions, and expression profiling shows new patterns. Conclusions: The research offers new insights into the BRX family’s role in foxtail millet’s growth and stress responses, laying a foundation for crop genetic improvement and enhancing stress resilience for global food security. Full article

Accurate, high-throughput canopy phenotyping using UAV-based multispectral remote sensing is critically important for optimizing the management and breeding of foxtail millet in rainfed regions. This study integrated multi-temporal field measurements of leaf water content, SPAD-derived chlorophyll, and leaf area index (LAI) with UAV imagery (red, green, red-edge, and near-infrared bands) across two sites and two consecutive years (2023 and 2024) in Shanxi Province, China. Various modeling approaches, including Random Forest, Gradient Boosting, and regularized regressions (e.g., Ridge and Lasso), were evaluated for cross-regional and cross-year extrapolation. The results showed that single-site modeling achieved coefficients of determination (R²) of up to 0.95, with mean relative errors of 10–15% in independent validations. When models were transferred between sites, R² generally remained between 0.50 and 0.70, although SPAD estimates exhibited larger deviations under high-nitrogen conditions. Even under severe drought in 2024, cross-year predictions still attained R² values near 0.60. Among these methods, tree-based models demonstrated a strong capability for capturing nonlinear canopy trait dynamics, whereas regularized regressions offered simplicity and interpretability. Incorporating multi-site and multi-year data further enhanced model robustness, increasing R² above 0.80 and markedly reducing average prediction errors. These findings demonstrate that rigorous radiometric calibration and appropriate vegetation index selection enable reliable UAV-based phenotyping for foxtail millet in diverse environments and time frames. Thus, the proposed approach provides strong technical support for precision management and cultivar selection in semi-arid foxtail millet production systems. Full article

Hexokinases (HXKs) in plants are multifunctional enzymes that not only phosphorylate hexose but also function as glucose sensors, integrating nutrient, light, and hormone signaling networks to regulate cell metabolism and signaling pathways, thereby controlling growth and development in response to environmental changes. To date, limited information is available regarding the HXKs of foxtail millet (Setaria italica L.). In this study, six HXK genes were identified and characterized in foxtail millet. Phylogenetic analysis revealed that the foxtail millet hexokinases were classified into three subfamilies, corresponding to the two types (B-type and C-type) of hexokinases in plants. Gene structure and conserved motif analysis showed that the SiHXKs exhibited varying numbers of introns and exons, with proteins in each subfamily showing similar motif organization. Evolutionary divergence analysis indicated that the foxtail millet HXK and green foxtail HXK genes families underwent both positive and negative selection and experienced a large-scale duplication event approximately 1.18–154.84 million years ago. Expression analysis revealed that these genes are widely expressed in roots, stems, leaves, panicles, anthers, and seeds, with most genes showing significantly increased expression in roots under abiotic stress conditions, including 20% PEG 6000 (drought stress), 200 μmol/L NaCl (salt stress), and 1 μmol/L BR (brassinosteroid-mediated stress response). These results suggest that these genes may play a pivotal role in enhancing stress tolerance. Subcellular localization assay showed that SiHXK5 and SiHXK6 were predominantly localized in mitochondria. Haplotype analysis revealed that SiHXK3-H1 was associated with higher plant height and grain yield. These findings provide valuable insights into the functional characteristics of HXK genes, especially in the context of marker-assisted selection and the pyramiding of advantageous haplotypes in foxtail millet breeding programs. Full article

Setaria viridis (green foxtail) is an invasive weed species in various agricultural systems, prompting the search for effective compounds to control its germination. The species has primary and secondary dormancy depending on the time elapsed since post-harvesting, making management strategies more difficult. Several weed plants, such as Lantana camara L., can be a source of allelochemicals with herbicidal effects, being a potential candidate for the control of S. viridis. We investigated the effects of L. camara extracts on the germination and initial growth of S. viridis seeds with different degrees of dormancy and revealed a dose-dependent bioherbicide effect. Aqueous extracts of L. camara were analyzed by HPLC-DAD and applied (0.1 to 5.0 mg/mL) to 12- and 110-day post-harvest S. viridis seeds. Seeds were evaluated daily and germination percentage (GP), speed germination index (SGI), and radicle length (RL) were calculated. Phenolic acids and flavonoids were major components of the extract. Lower concentrations (0.1 and 0.5 mg/mL) stimulated and accelerated the germination of S. viridis, breaking its dormancy. Both 1.0 and 5.0 mg/mL concentrations hindered germination, especially in 12 dph seeds. The 1.0 mg/mL concentration resulted in longer roots, whereas 5.0 mg/mL inhibited root development. Lantana camara extracts potentially stimulate germination and radicle growth of S. viridis at low concentrations while inhibiting these parameters at higher doses. These results may open new possibilities for using L. camara in weed-control strategies. Full article

Green foxtail is a troublesome weed in crop fields across China. A nova target HPPD inhibitor is widely used to control weeds in agricultural production. Mesotrione, an HPPD inhibitor, cannot control green foxtail effectively under the recommended field dose, indicating that green foxtail is tolerant to mesotrione. Interestingly, a green foxtail biotype that exhibits a greater tolerance to mesotrione (GR₅₀ value 463.2 g ai ha⁻¹) than that of the wild biotype (GR₅₀ value 271.9 g ai ha⁻¹) was found in Jilin Province, China. The HPPD genes isolated from the two biotypes genome were aligned, while no difference was found in the amino acid of the HPPD compared with that of the wild biotype. Through the qPCR experiment, the HPPD gene copy number variation and overexpression were also not found. Cytochrome P450 inhibitors (malathion and PBO), pretreatment, could effectively reverse the tolerance. Compared with the MT biotype, the in vivo activity of P450s was higher after the mesotrione treatment in the HT biotype. Therefore, P450s might be involved in the mechanism of tolerance. Full article

WUSCHEL-related homeobox (WOX) transcription factors are unique to plants and play pivotal roles in plant development and stress responses. In this investigation, we acquired protein sequences of foxtail millet WOX gene family members through homologous sequence alignment and a hidden Markov model (HMM) search. Utilizing conserved domain prediction, we identified 13 foxtail millet WOX genes, which were classified into ancient, intermediate, and modern clades. Multiple sequence alignment results revealed that all WOX proteins possess a homeodomain (HD). The SiWOX genes, clustered together in the phylogenetic tree, exhibited analogous protein spatial structures, gene structures, and conserved motifs. The foxtail millet WOX genes are distributed across 7 chromosomes, featuring 3 pairs of tandem repeats: SiWOX1 and SiWOX13, SiWOX4 and SiWOX5, and SiWOX11 and SiWOX12. Collinearity analysis demonstrated that WOX genes in foxtail millet exhibit the highest collinearity with green foxtail, followed by maize. The SiWOX genes primarily harbor two categories of cis-acting regulatory elements: Stress response and plant hormone response. Notably, prominent hormones triggering responses include methyl jasmonate, abscisic acid, gibberellin, auxin, and salicylic acid. Analysis of SiWOX expression patterns and hormone responses unveiled potential functional diversity among different SiWOX genes in foxtail millet. These findings lay a solid foundation for further elucidating the functions and evolution of SiWOX genes. Full article

The green foxtail, Setaria viridis (L.) P. Beauv. (Poales: Poaceae), is a troublesome and widespread grass weed in China. The acetolactate synthase (ALS)-inhibiting herbicide nicosulfuron has been intensively used to manage S. viridis, and this has substantially increased the selection pressure. Here we confirmed a 35.8-fold resistance to nicosulfuron in an S. viridis population (R376 population) from China and characterized the resistance mechanism. Molecular analyses revealed an Asp-376-Glu mutation of the ALS gene in the R376 population. The participation of metabolic resistance in the R376 population was proved by cytochrome P450 monooxygenases (P450) inhibitor pre-treatment and metabolism experiments. To further elucidate the mechanism of metabolic resistance, eighteen genes that could be related to the metabolism of nicosulfuron were obtained bythe RNA sequencing. The results of quantitative real-time PCR validation indicated that three ATP-binding cassette (ABC) transporters (ABE2, ABC15, and ABC15-2), four P450 (C76C2, CYOS, C78A5, and C81Q32), and two UDP-glucosyltransferase (UGT) (UGT13248 and UGT73C3), and one glutathione S-transferases (GST) (GST3) were the major candidates that contributed to metabolic nicosulfuron resistance in S. viridis. However, the specific role of these ten genes in metabolic resistance requires more research. Collectively, ALS gene mutations and enhanced metabolism may be responsible for the resistance of R376 to nicosulfuron. Full article

Foxtail millet (Setaria italica (L.) P. Beauv.) is an important traditional cereal crop in dryland ecological agriculture in China and is widely grown in India, the United States, and Nigeria. It is of significance to understand the variety–location–fertilizer (V–L–F) interaction for highly efficient production. Therefore, a two-year field experiment was conducted with six varieties in five locations, and data were analyzed by combined ANOVA analysis, redundancy analysis (RDA), and additive main multiplicative interaction (AMMI). The results showed that the mean sum of squares was significantly different among years, locations, varieties, fertilizations, and their interactions, except for Y–V and V–F interactions. The contributions of various factors to yield variation varied, location was the largest contributor (38.7%), followed by year (33.6%), and variety and fertilizer contributed 7.1% and 3.2%, respectively. JI25 was widely adapted, and its yield was stable and higher than that of others over diverse environments in two years. The RDA results showed that two principal components explained more than 66.1% of the yield variance, while more than 63.0% of the variances were clustered in the first factor. Excessive single rainfall or total rainfall and air temperature (especially minimum temperature) were significantly associated with the millet yield. The results offered an important reference for variety layout, natural resource potential mining, and formulation of efficient green cultural practices. Full article

The maize pathogen Magnaporthiopsis maydis causes severe damage to commercial fields in the late growth stages. This late wilt disease has spread since its discovery (the 1980s) and is now common in most corn-growing areas in Israel. In some fields and sensitive plant species, the disease can affect 100% of the plants. The M. maydis pathogen has a hidden endophytic lifecycle (developed inside the plants with no visible symptoms) in resistant corn plants and secondary hosts, such as green foxtail and cotton. As such, it may also be opportunist and attack the host in exceptional cases when conditions encourage it. This work aims to study the pathogen’s interactions with maize endophytes (which may play a part in the plant’s resistance factors). For this purpose, 11 fungal and bacterial endophytes were isolated from six sweet and fodder corn cultivars with varying susceptibility to late wilt disease. Of these, five endophytes (four species of fungi and one species of bacteria) were selected based on their ability to repress the pathogen in a plate confrontation test. The selected isolates were applied in seed inoculation and tested in pots in a growth room with the Prelude maize cultivar (a late wilt-sensitive maize hybrid) infected with the M. maydis pathogen. This assay was accompanied by real-time qPCR that enables tracking the pathogen DNA inside the host roots. After 42 days, two of the endophytes, the Trichoderma asperellum, and Chaetomium subaffine fungi, significantly (p < 0.05) improved the infected plants’ growth indices. The fungal species T. asperellum, Chaetomium cochliodes, Penicillium citrinum, and the bacteria Bacillus subtilis treatments were able to reduce the M. maydis DNA in the host plant’s roots. Studying the maize endophytes’ role in restricting the invasion and devastating impact of M. maydis is an essential initial step towards developing new measures to control the disease. Such an environmentally friendly control interface will be based on strengthening the plants’ microbiome. Full article

Setaria viridis (L.) Beauv., or green foxtail, is native to Eurasia and is the putative ancestor of foxtail millet. Due to the advantageous genetic characteristics of S. viridis, it is a model species for C4 plants. However, S. viridis has seriously spread to the agricultural system around the world because of its wide adaptability. This study is aimed to understand the distribution of S. viridis in Taiwan, and also to investigate the genetic diversity and relationships among different wild populations. A total of 141 S. viridis collected at 10 sites with sampling sizes ranging from 8 to 24 plants in Taiwan were analyzed by 13 highly polymorphic SSR markers, and 6.1 alleles per locus were detected in our study. The relationships of collected S. viridis mostly corresponded to its distribution in different parts of Taiwan revealed by PCoA and phylogenetic tree. Similarly, the results for population structure showed the significance of collecting site or geographical factors. Finally, the extent of gene flow was studied with the genetic differentiation (F_ST) and Nm values, and two S. viridis populations were found to significantly contain the existence of gene-flow events. In conclusion, S. viridis showed a pattern of low diversity and heterozygosity within a population, but high differentiation among populations because of its selfing attribute and the barriers of sea and mountain range for gene flow. In addition, the founder effect may be the other reason for this pattern of population genetic structure. Full article

C₄ plants play a key role in world agriculture and strategies to manipulate and enhance C₄ photosynthesis have the potential for major agricultural impacts. The C₄ photosynthetic pathway is a biochemical CO₂ concentrating mechanism that requires the coordinated functioning of mesophyll and bundle sheath cells of leaves. Chloroplast electron transport in C₄ plants is shared between the two cell types; it provides resources for CO₂ fixation therefore underpinning the efficiency of photosynthesis. Using the model monocot C₄ species Setaria viridis (green foxtail millet) we demonstrated that the Cytochrome (Cyt) b₆f complex regulates the electron transport capacity and thus the rate of CO₂ assimilation at high light and saturating CO₂. Overexpression of the Cyt b₆f in both mesophyll and bundle sheath cells results in a higher electron throughput and allows better light conversion efficiency in both photosystems. Importantly, increased Cyt b₆f abundance in leaves provides higher rates of C₄ photosynthesis without marked changes in Rubisco or chlorophyll content. Our results demonstrate that increasing the rate of electron transport is a viable strategy for improving the light conversion efficiency in C₄ crop species like maize and sorghum. Full article

The fungus Magnaporthiopsis maydis is a soil-borne, seed-borne vascular wilt pathogen that causes severe damage to sensitive Zea mays L. (maize) hybrids throughout Egypt, Israel, India, Spain, and other countries. It can undergo virulence variations and survive as spores, sclerotia, or mycelia on plant residues. Maize, Lupinus termis L. (lupine) and Gossypium hirsutum L. (cotton) are the only known hosts of M. maydis. Identification of new plant hosts that can assist in the survival of the pathogen is an essential step in restricting disease outbreak and spread. Here, by field survey and growth chamber pathogenicity test, accompanied by real-time PCR analysis, the presence of the fungal DNA inside the roots of cotton (Pima cv.) plants was confirmed in infested soil. Moreover, we identified M. maydis in Setaria viridis (green foxtail) and Citrullus lanatus (watermelon, Malali cv.). Infected watermelon sprouts had delayed emergence and development, were shorter, and had reduced root and shoot biomass. M. maydis infection also affected root biomass and phenological development of cotton plants but caused only mild symptoms in green foxtail. No M. maydis DNA was detected in Hordeum vulgare (barley, Noga cv.) and the plants showed no disease symptoms except for reduced shoot weight. These findings are an important step towards uncovering the host range and endophytic behavior of M. maydis, encouraging expanding this evaluation to other plant species. Full article