ABSTRACT Background and Aim Changes in temperature and nitrogen deposition associated with altered climatic conditions are likely to significantly alter rates of soil organic matter decomposition. However, our current knowledge about how warming and nitrogen deposition interactively alter mineralization of soil organic carbon is largely limited. Methods Therefore, we selected a herbaceous marsh in the Funiu Mountain for a field simulation experiment of warming and nitrogen deposition. Results We found that, in the topsoil layer, nitrogen deposition significantly decreased the carbon pool management index (CPMI) and increased soil respiration flux, whereas neither warming nor its interaction with nitrogen deposition significantly affected either of these two indicators. Partial least squares path modeling (PLS‐PM) analysis revealed that nitrogen deposition accelerates soil carbon decomposition by increasing cellobiohydrolase activity and decreasing microbial carbon use efficiency (CUE), whereas warming reduces soil labile carbon content. Both of these processes contribute to a decrease in the soil CPMI, which ultimately promotes the enhancement of soil respiration. This study revealed a significant interactive effect of warming and nitrogen deposition on wetland soil respiration. Specifically, nitrogen deposition accelerates soil carbon release by activating microbial carbon‐acquiring enzymes and decreasing microbial CUE, whereas warming indirectly promotes respiration by reducing labile carbon content. Conclusion Our findings provided key parameters for the development of climate‐carbon cycle feedback models and offered a theoretical basis for formulating protection strategies for wetland carbon sink functions.

As a core process in the terrestrial carbon cycle, soil microbial respiration (SMR) is strictly regulated by the elemental balance between microbial metabolic demands and available resources. However, the influence of stoichiometric imbalances on microbial metabolic strategies and carbon release along the elevation gradient remains unclear. In this study, five typical forest belts, comprising Acer truncatum (>1700 m), Quercus aliena var. acuteserrata (1500-1700 m), Anacardiaceae (1300-1500 m), Quercus serrata var. brevipetiolata (1000-1300 m), and Quercus variabilis (<1000 m) at different elevational gradients in the Funiu Mountains were selected. Soil nutrients, extracellular enzyme activity, microbial biomass and community structure, and SMR were measured to analyse the regulatory mechanisms of stoichiometric imbalance in the carbon cycle. Microbial nutrient limitation changed significantly along the elevation gradient, shifting from N-P co-limitation at lower elevations to P limitation at higher elevations. Although a stoichiometric imbalance existed along the elevation gradient, the C: N:P ratio between soil resources and microbial biomass showed no significant correlation, suggesting that the microbial communities maintained strict homeostasis. The C:P imbalance was significantly negatively correlated with carbon use efficiency (CUE), indicating that under conditions where carbon was more abundant than phosphorus, soil microorganisms regulated respiration to release more carbon, reducing CUE. The random forest results showed that microbial beta diversity and bacterial phyla (e.g., Acidobacteria, Firmicutes) were key factors responding to stoichiometric imbalance. The partial least squares path model (PLS-PM; GOF = 0.76) revealed that elevation-induced C:N:P imbalance could directly negatively regulate SMR or indirectly drive changes in SMR by regulating extracellular enzyme activity and microbial community structure. Polynomial regression analysis validated the robustness of the PLS-PM core pathways. The findings highlight a mechanism by which stoichiometric imbalance shapes microbial metabolism to influence carbon release, providing data support for refining terrestrial ecosystem carbon budget models.

Background Global climate change is rapidly impacting biodiversity and threatening the sustainable use of medicinal plant species by reducing their availability and increasing harvest uncertainty. Understanding the adaptive genetic variation and genetic vulnerability of medicinal plants under climate change is crucial for effective germplasm management, cultivation, and breeding efforts. In this study, we assessed the genetic differentiation, local adaptation, and genomic vulnerability of the medicinal plant Isodon rubescens (Hemsl.) H. Hara, with the goals of elucidating the impacts of geographic and environmental factors on its genetic structure and identifying at-risk populations for informed conservation and breeding under climate change. Results We applied restriction site-associated DNA sequencing (RAD-seq) to 17 populations of I. rubescens spanning its central and peripheral ranges, including the Taihang and Qinling-Funiu Mountains. The analysis revealed two distinct genetic groups: one in the Taihang Mountains and the other in the Qinling-Funiu Mountains. Significant patterns of isolation by distance (IBD), environment (IBE), and resistance (IBR) were detected, alongside high niche differentiation. We identified 456 candidate adaptive SNPs, some linked to genes involved in stress responses and biosynthesis. Precipitation was a key environmental driver of local adaptation. Populations in the northern Taihang Mountains and southern Funiu Mountains showed higher genomic vulnerability, indicating a greater risk of maladaptation. Conclusion Our findings demonstrate that geographic isolation and environmental factors, particularly precipitation, are key drivers of genetic differentiation and local adaptation in I. rubescens . The identified genomic vulnerability pinpoints specific populations at high risk under climate change. These insights provide a crucial genetic basis for formulating targeted conservation strategies and developing climate-resilient breeding programs for this medicinal species.

Non-histone deacetylation is a widespread and reversible post-translational modification (PTM) dynamically regulated by histone acetyltransferases (HATs) and histone deacetylases (HDACs). Although initially characterized as a chromatin-associated mechanism controlling transcription, recent discoveries demonstrate that HDAC-mediated non-histone deacetylation extends far beyond gene regulation, targeting diverse transcription factors and functional proteins across cellular pathways. Here, we summarize advances in Arabidopsis, rice, and wheat recently, highlighting how non-histone deacetylation modulates protein stability and activity, and crosstalk with other PTMs to regulate developmental processes and coordinate plant responses to abiotic (salt, heat, cold, drought) and biotic (viral, fungal, oomycete) stresses. We further emphasize mechanistic insights establishing non-histone deacetylation as a flexible, multilayered regulatory system that fine-tunes crop growth and stress resilience, and propose that environmentally driven dynamic HDAC–HAT antagonism operates as a molecular switch balancing these processes. A deeper understanding of these regulatory networks provides new opportunities for rational crop design through molecular breeding and genome editing.

Covering: up to the end of 2025.Plant specialized metabolites shape plant color, aroma, and stress adaptation while providing high-value natural products. Although transcription factors have long been regarded as central regulators of specialized-metabolite biosynthesis, increasing evidence indicates that chromatin-associated epigenetic regulatory mechanisms provide additional layers of control over transcriptional responsiveness, chromatin accessibility, and metabolic output. Here, we briefly discuss how distinct epigenetic regulatory mechanisms, including DNA methylation, chromatin remodeling, histone methylation, and histone acetylation, contribute to plant specialized metabolism through different regulatory principles. Among these mechanisms, histone acetylation/deacetylation appears particularly important for rapidly reversible and environmentally responsive transcriptional regulation. Using anthocyanin biosynthesis as the most mechanistically resolved paradigm, we highlight how dynamic histone acetylation integrates environmental and phytohormonal cues with transcriptional networks to fine-tune metabolic gene expression. This framework provides new insights into chromatin-mediated metabolic regulation and offers opportunities for achieving precise, predictable, and durable metabolic engineering in plants.

Brassica crops, well known for their nutritional and medicinal value, encompass a diverse range of species and varieties, many of which are rich in anthocyanins. These flavonoid pigments not only contribute to the vibrant colors of Brassica plants but also possess significant antioxidant, anti-inflammatory, and neuroprotective properties. This review provides an in-depth analysis of the distribution, composition, and health benefits of anthocyanins in Brassica crops, highlighting their potential applications in the food industry and medicine. We discuss the accumulation patterns of anthocyanins in various Brassica tissues, the influence of genetic and environmental factors on their concentration, and the impact of acylation on their stability and biological activities. This review also explores the antioxidant capacity and cardioprotective effects of Brassica anthocyanins, as well as their roles in protecting against hepatic and renal injury and promoting neuroprotection. Furthermore, we examine the use of anthocyanins as natural food colorants and their integration into intelligent packaging for the real-time monitoring of food freshness. Our findings underscore the multifaceted benefits of Brassica anthocyanins, positioning them as key components in the development of functional foods and sustainable food systems.

Pulmonary hypertension (PH) is a devastating disease marked by elevated pulmonary artery pressure, resulting in right ventricular (RV) failure and mortality. Despite the identification of several dysregulated genes in PH, the involvement of circular RNAs (circRNAs), a subset of long noncoding RNAs, remains largely unknown. In this study, high-throughput RNA sequencing was performed to analyze the genome-wide expression patterns of circRNAs in pulmonary arteries from three models of PH rats induced by hypoxia (Hyp), hypoxia/Sugen5416 (HySu), and monocrotaline (MCT). Differentially expressed circRNAs (DEcircRNAs) were identified, and a weighted gene coexpression network was constructed to explore circRNA networks associated with PH pathogenesis. A circRNA-miRNA-mRNA regulatory network was built, and the functional significance of targeted mRNAs was evaluated. Single-cell RNA sequencing provided insights into the distribution of cell type-specific circRNAs across PH progression. Our analysis revealed 45 circRNAs exhibiting significant changes across all three PH rat models, with their host genes participating in the calcium signaling and muscle contraction. We identified 372 PH-related circRNA-miRNA-mRNA interactions, shedding light on the regulatory networks during PH development. Furthermore, we uncovered 186, 195 and 311 Hyp-, Hysu- and MCT-specific circRNAs, respectively. These circRNAs were enriched in distinct biological processes, emphasizing their unique regulatory roles. Single-cell spatial distribution analysis of these circRNAs in the pulmonary arteries of PH patients revealed that Hyp-specific circRNA predominantly appeared in the pulmonary vascular structural cells, while HySu- and MCT-specific circRNAs exhibited broader distribution, including significant enrichment in immune-related cells. Our study presents the first comprehensive view of circRNA regulatory networks in the pulmonary arteries of three PH rat models. We provide insights into PH-associated circRNAs, particularly their involvement in calcium signaling and muscle contraction.

The forest ecosystem is a significant pool for capturing atmospheric mercury (Hg) deposition, with most Hg accumulating in forest soils. As secondary forests now dominate global forest cover, they are particularly sensitive to changes in ambient temperature. However, the impact of these changes on Hg dynamics in secondary forests remains poorly understood. Here, we quantified Hg inputs, outputs, and mass balances in two secondary forests in China, each with different ambient temperatures. We found that elevated ambient temperature (similar to 1.0 degrees C) advanced the germination of leaves by 2-3 days and extended the growing season by approximately one week, resulting in increased litterfall biomass by 1.18 Mg hm(-2) yr(-1) and a thicker litterfall layer by 0.22 cm over 34 years. This temperature rise also facilitated Hg methylation within forest and enhanced methylmercury (MeHg) export, heightening the potential risk of MeHg exposure to surrounding ecosystems. Additionally, higher ambient temperature not only increased soil Hg emissions (2.75 mu g m(-2) yr(-1)) but also led to significant Hg deposition via litterfall (9.26 mu g m(-2) yr(-1)), resulting in a net annual Hg deposition of 6.88 mu g m(-2) yr(-1). This net Hg deposition accumulated in the topsoil, increasing the Hg pool by 0.51 mg m(-2) in organic and 0-10 cm mineral soil horizons. Our findings suggest that even a similar to 1.0 degrees C temperature rise could enhance the role of secondary forests as atmospheric Hg sink by 45.10 %. Therefore, the impact of ongoing climate warming on Hg cycling and pools in forests should receive increased attention and warrants further research.

Microbial resource limitation and metabolic processes synergistically regulate soil carbon dynamics through multiple mechanisms. Elevation gradient shapes soil microbial resource limitation patterns, yet how microbial metabolic processes adapt to resource limitation along elevation gradient remains poorly understood. In this study, we collected soil samples at five altitudinal sites (860, 1230, 1360, 1510, and 1810 m), to analyze soil microbial resource limitation and metabolic activities. The results showed that elevation gradient significantly affected soil properties, enzyme activities, microbial biomass, and related stoichiometries (p < 0.05). With the increase in altitude, vector length (VL) decreased from 1.62 to 1.58, while vector angle (VA) increased from 25.47 degrees to 33.02 degrees, indicating microbial communities generally exhibited co-limitation by carbon and nitrogen, whereas the intensity of co-limitation alleviated with increasing altitude. This pattern was primarily attributed to adaptive stoichiometric adjustments of microbial extracellular enzymes involved in nutrient acquisition. Meanwhile, simulation models of microbial metabolic processes showed that both organic carbon decomposition rate (M) and microbial respiration rate (Rm) significantly increased with elevation (p < 0.05). Specifically, M rose from 11.66 % day- 1 to 16.18 % day(-1), and Rm increased from 251.46 mmol C m(-3) day(-1) to 1089.71 mmol C m(-3) day(-1). Random Forest results indicated soil enzyme stoichiometric ratios as major factors influencing soil microbial metabolism. Through integrating resource limitation theory with microbial metabolic simulation models, we have revealed the adaptive strategies of high-altitude microorganisms to enhance carbon turnover by alleviating resource limitation. This study provides a scientific foundation for predicting and managing forest ecosystems affected by resource limitations.

Peanut seeds exhibit a high susceptibility to infection by Aspergillus flavus (A. flavus) post-harvest, which significantly limits their storage and marketability. The peanut seed coat acts as a crucial barrier against A. flavus, containing abundant flavonoids. Despite ongoing research, a comprehensive understanding of the inhibitory effects of flavonoids present in peanut seed coats on A. flavus remains elusive. This study reveals significant differences in antioxidant activities and resistance to A. flavus among seed coat extracts from different peanut cultivars. A total of 1,314 metabolites were identified through untargeted metabolomics, among which flavonoids enhance both antioxidant activity and pigmentation in the seed coat. Compounds such as anthocyanins, aurones, and chalcones were strongly associated with increased resistance to A. flavus. Notably, cyanidin-3-O-sophoroside exhibited the highest concentration (10.83 mg/g dry weight) and demonstrated a minimum inhibitory concentration (MIC) of 50 µg/mL. By integrating transcriptomic and metabolomic data, we revealed candidate genes and metabolic pathways potentially associated with anthocyanin biosynthesis. This study provides novel insights into the biochemical mechanisms underlying peanut resistance to A. flavus, while also supporting the valorization of peanut by-products and the breeding of resistant cultivars.

Brassica carinata has gained traction as an alternative biofuel feedstock in many countries, and serves as a well-known dual-purpose crop for both oilseed and leafy vegetable production. The purple varieties, which are rich in anthocyanins, are usually more eye-catching and beneficial to health. In this study, eleven cyanidin 3-glycoside-5-glucoside derivatives with different acyl modifications were characterized in two purple varieties of B. carinata (ZJC, which has an obvious purple stem, and ZJ, which has both purple stems and leaves) using an ultra-high performance liquid chromatography (UHPLC) system coupled with a high-resolution mass spectrometer (HRMS). In ZJ, the main anthocyanins are modified with a malonyl group at the C5 position, whereas such modifications are not found in ZJC. A total of 141 anthocyanin biosynthetic genes (ABGs) were identified in the B. carinata genome, and these genes were combined with the comparative transcriptome analysis based on RNA-Seq of leaves and stem peel from two purple varieties and one green variety to investigate the mechanisms underlying anthocyanin accumulation. A comprehensive synthetic and regulatory pathway for anthocyanin biosynthesis was proposed for B. carinata, and the ABGs in the pathway, particularly the late biosynthetic and transport genes, were predominantly regulated at the transcriptional level in pigmented tissues. Furthermore, the R2R3 MYB transcription factor BcaB05. MYB114 was verified as a crucial and conserved regulator of anthocyanin biosynthesis through its interactions with TT8 and TTG1 in Brassica species. This study opens new avenues for engineering anthocyanin-enriched B. carinata with improved horticultural quality.

Rapid climate change is affecting biodiversity and threatening locally adapted species. Relict species are often confined to relatively narrow, discontinuous geographic ranges and provide excellent opportunities to study local adaptation and extinction. Understanding the adaptive genetic variation and genetic vulnerability of relict species under climate change is essential for their conservation and management efforts. Here, we applied a landscape genomics approach to investigate the population genetic structure and predict adaptive capacity to climatic change for Taiwania cryptomerioides Hayata, a vulnerable Tertiary relict tree species in China. We used restriction site-associated DNA sequencing on 122 individuals across 10 sampling sites. We found three genetic groups across the Chinese range of T. cryptomerioides: the southwest, central-eastern, and Taiwanese groups. We detected significant signals of isolation by environment and isolation by distance, with environment playing a more important role than geography in shaping spatial genetic variation in T. cryptomerioides. Moreover, some outliers were related to defense and stress responses, which could reflect the genomic basis of adaptation. Gradient forest (GF) analysis revealed that precipitation-related variables were important in driving adaptive variation in T. cryptomerioides. Ecological niche modeling and GF analysis revealed that the central-eastern populations were more vulnerable to future climate change than other populations, with range contractions and high genetic offsets, suggesting these populations may be at higher risk of decline or local extinction. These findings deepen our understanding of local adaptation and vulnerability to climate change in relict tree species and will guide conservation and restoration programs for T. cryptomerioides in the future.

Vegetation restoration has been widely implemented to restore degraded land. However, vegetation expansion may result in the overconsumption of soil moisture and soil desiccation, which in turn exacerbates land degradation. To ensure the sustainability of ecological restoration, it is necessary to optimise restoration patterns. Two restoration patterns (afforestation with Robinia pseudoacacia L. (RP) and abandoned farmland (AL)) along a revegetation chronosequence (0, 9, 17, 27, and 42 years) were selected to analyse variations in soil and hydrological characteristics on the Loess Plateau, China. The results showed that for the two revegetation types, the soil quality index (SQI) increased markedly (p < 0.05) and the soil loss (SL) and surface runoff (R) decreased significantly (p < 0.05) over time, indicating that vegetation restoration improves soil quality and prevents soil and water erosion. The annual increments of soil moisture storage (Ws) within a 200 cm depth notably decreased during the late restoration stage (> 27 years) for the artificial forest. Moreover, forest also showed increasing actual evapotranspiration (ET) trends and decreasing Ws trends. These results suggest that afforestation might lead to overconsumption of water and soil water depletion during the late restoration stage. Although RP sites had higher SQI (22.2-36.7 %) values and lower SL (47.0-81.4 %) and R (86.5-196.8 %) values when compared with AL sites, the change rates of the SQI, R, and SL at RP sites were stable or decreased over a period of restoration, while these rates showed increasing tendencies under AL sites. These suggests that natural grasslands may be more beneficial than artificial forests during the late restoration stage. Therefore, naturally restored grasslands are highly recommended for sustainable ecological restoration in the semiarid and arid areas of the Loess Plateau or in similar areas elsewhere.

Osteoporosis is a common systemic skeletal disease and a predominant underlying factor in the increased occurrence of fractures. The structure of isoflavones resembles that of estrogen and can confer similar but weaker effects. This study investigated the potential inhibitory effects of isoflavones from chickpea sprouts (ICS) on ovariectomy (OVX)-induced osteoporosis in vitro and in vivo. Notably, we found that ICS treatment could attenuate bone loss and improve trabecular microarchitecture and biomechanical properties of the fourth lumbar vertebra in OVX-induced osteoporotic rats and could also inhibit the development of a hyperosteometabolic state in this model. The osteogenic differentiation of bone marrow stem cells (BMSCs) was significantly enhanced by ICS intervention in vitro, and we confirmed that estrogen receptor α signaling was required for this increased osteogenic differentiation. Additionally, ICS has been shown to inhibit bone resorption via ERa modulation of the OPG/RANKL pathway. RANKL-induced osteoclastogenesis was reduced under ICS treatment, supporting that NF-κB signaling was inhibited by ICS. Thus, ICS attenuates osteoporosis progression by promoting osteogenic differentiation and inhibiting osteoclastic resorption. These results support the further exploration and development of ICS as a pharmacological agent for the treatment and prevention of osteoporosis.

Rapeseed (Brassica napus L.) is susceptible to nutrient stresses during growth and development; however, the CPA (cation proton antiporter) family genes have not been identified in B. napus and their biological functions remain unclear. This study was aimed to identify the molecular characteristics of rapeseed CPAs and their transcriptional responses to multiple nutrient stresses. Through bioinformatics analysis, 117 BnaCPAs, consisting of three subfamilies: Na+/H+ antiporter (NHX), K+ efflux antiporter (KEA), and cation/H+ antiporter (CHX), were identified in the rapeseed genome. Transcriptomic profiling showed that BnaCPAs, particularly BnaNHXs, were transcriptionally responsive to diverse nutrient stresses, including Cd toxicity, K starvation, salt stress, NH4+ toxicity, and low Pi. We found that the salt tolerance of the transgenic rapeseed lines overexpressing BnaA05.NHX2 was significantly higher than that of wild type. Subcellular localization showed that BnaA05.NHX2 was localized on the tonoplast, and TEM combined with X-ray energy spectrum analysis revealed that the vacuolar Na+ concentrations of the BnaA05.NHX2-overexpressing rapeseed plants were significantly higher than those of wild type. The findings of this study will provide insights into the complexity of the BnaCPA family and a valuable resource to explore the in-depth functions of CPAs in B. napus.

Assessing the relationship between litter characteristics and soil microbial community traits across different forest types can enhance our understanding of the synergistic interactions among litter, soil, and microorganisms. This study focused on three representative forest types in the Funiu Mountains—Larix gmelinii (LG), Quercus aliena var. acutiserrata (QA), and Quercus aliena var. acutiserrata + Pinus armandii (QAPA). The findings indicated no significant differences in Chao1 among the three forests; however, the Shannon index exhibited an initial increase followed by a decline. NMDS and ANOSIM analyses revealed significant structural differences across these forest types. Network topological metrics (nodes, edges, average degree, and average path distance) for bacterial taxa were higher in LG and QA compared with QAPA. Additionally, LG and QA demonstrated significantly greater average niche breadth than QAPA. The results from the null models (the proportion occupied by dispersal limitation is 62.2%, 82.2%, and 64.4% in LG, QA, and QAPA), modified stochasticity ratio (LG: 0.708, QA: 0.664, and QAPA: 0.801), and neutral community models (LG: R2 = 0.665, QA: R2 = 0.630, and QAPA: R2 = 0.665) suggested that stochastic processes predominantly govern the assembly of soil bacterial communities. Random forest analysis alongside Mantel tests highlighted LTP (litter total phosphorus), STN (soil total nitrogen), MCP (carbon-to-phosphorus ratio of microbial biomass), and SCN (soil carbon-to-nitrogen ratio) as critical factors affecting bacterial niche width; conversely LCN (litter carbon-to-nitrogen ratio), RCP (ratio of dissolved carbon to phosphorus), MCP, and SCN emerged as key determinants influencing community assembly processes. Furthermore, the PLS-SEM results underscored how both litter characteristics along with soil properties—and their associated alpha diversity—impact variations in niche breadth while also shaping community assembly dynamics overall. This research provides vital insights into understanding synergistic relationships between litter quality, soil characteristics, and microbial community across diverse forest ecosystems.

Snail mucus is rich in proteins and polysaccharides, which has been proved to promote wound healing in mice in our previous research. The aim of this study was to investigate the effective component in snail mucus that can exert the wound healing potential and its structural characterization. Here, the glycoprotein from the snail mucus (SM1S) was obtained by DEAE-Sepharose Fast Flow and Sephacryl S-300 columns. The structural characteristics of SM1S were investigated via chromatographic techniques, periodic acid oxidation, FT-IR spectroscopy and NMR spectroscopy. Results showed that SM1S was a glycoprotein with a molecular weight of 3.8 kDa (83.23 %), consists of mannose, glucuronic acid, glucose, galactose, xylose, arabinose, fucose at a ratio of 13.180:4.875:1043.173:7.552:1:3.501:2.058. In addition, the periodic acid oxidation and NMR analysis showed that SM1S contained 1,6-glycosidic bonds, and might also contain 1 → 4 and 1 → 2 glycosidic or 1 → 3 glycosidic bonds. Furthermore, the migration experiment of human skin fibroblasts in vitro suggested that SM1S had a good effect to accelerate the scratch healing of cells. This study suggested that SM1S may be a prospective candidate as a natural wound dressing for the development of snail mucus products.

Cornus officinalis Siebold & Zucc. is an important Chinese herbal medicine with traditional clinical applications, a long history of cultivation and high economic value in China. C. officinalis is distributed mainly in the Shaanxi, Henan, and Zhejiang provinces of China, which are also historically the main production areas, and which still provide 90% of the medicinal material of this species for the contemporary market. In this study, we investigated the main germplasm resources of C. officinalis across its distribution, based on fruit morphology, the concentrations of selected medicinally active ingredients, and molecular population genetic analysis. The results indicated that the C. officinalis populations sampled had abundant variation in fruit morphology and chemical component content, and showed high genetic diversity, as revealed by microsatellite markers. Clustering results based on morphology, active ingredient concentration and microsatellite markers supported the idea that populations from Zhejiang province were distinct from those in Shaanxi and Henan. The fruit and molecular data suggested that the Shaanxi and Henan populations were mixed, which could be attributed to their close geographical distance and frequent germplasm exchange. Most of the C. officinalis populations had relatively weak genetic differentiation from others sampled, and most of the individuals sampled showed extensive admixture. We suggest that artificial gene flow caused by intensive cultivation and widespread trading is responsible for the observed admixture of genetic components and blurred genetic boundaries between C. officinalis populations, especially in the Shaanxi and Henan populations. We also propose some suggestions for the efficient utilization and conservation of C. officinalis germplasm. These findings provide valuable information on the genetic resources of C. officinalis and offer guidelines for breeding programs and scientific management of C. officinalis.

Variations in the resistance to potassium (K) deficiency among rapeseed genotypes emphasize complicated regulatory mechanisms. In this study, a low-K-sensitivity accession (L49) responded to K deficiency with smaller biomasses, severe leaf chlorosis, weaker photosynthesis ability, and deformed stomata morphology compared to a low-K resistant accession (H280). H280 accumulated more K+ than L49 under low K. Whole-genome resequencing (WGS) revealed a total of 5,538,622 single nucleotide polymorphisms (SNPs) and 859,184 insertions/deletions (InDels) between H280 and L49. RNA-seq identified more differentially expressed K+ transporter genes with higher expression in H280 than in L49 under K deficiency. Based on the K+ profiles, differential expression profiling, weighted gene coexpression network analysis, and WGS data between H280 and L49, BnaC4.AKT1 was proposed to be mainly responsible for root K absorption-mediated low K resistance. BnaC4.AKT1 was expressed preferentially in the roots and localized on the plasma membrane. An SNP and an InDel found in the promoter region of BnaC4.AKT1 were proposed to be responsible for its differential expression between rapeseed genotypes. This study identified a gene resource for improving low-K resistance. It also facilitates an integrated knowledge of the differential physiological and transcriptional responses to K deficiency in rapeseed genotypes.