Search Results (528)

Q-type C2H2 zinc finger protein (ZFP) transcription factors, a plant-specific subfamily of C2H2 ZFP, have been implicated in regulating abiotic stress responses, growth, and developmental processes in plants. Rapeseed (Brassica napus L.) is a crucial oil crop widely used for the production of high-quality vegetable oil, animal feed, and biodiesel. Compared with studies on Q-type C2H2-ZFP genes in other plant species, systematic research has not been performed in B. napus. In this study, a comprehensive genome-wide analysis of Q-type C2H2-ZFPs in B. napus was conducted. A total of 216 Q-type C2H2-ZFP genes were identified, exhibiting extensive and uneven distribution across the 19 chromosomes. Phylogenetic analysis, based on homologs from Arabidopsis, classified these genes into eight distinct subfamilies, with each containing one to three conserved “QALGGH” motifs. Each subfamily exhibited similar motif compositions and gene structures. Evolutionary studies revealed that segmental duplication events played a crucial role in the expansion of the BnaQ-type C2H2-ZFP gene family. Expression pattern analysis in different tissues and under abiotic stress identified BnaA03g09250D, BnaC09g35160D, BnaC03g11570D, and BnaA10g25850D as candidate genes involved in the response to freezing stress. Overexpression of BnaC09g35160D provided preliminary evidence that it enhances freezing tolerance in plants. This comprehensive study of Q-type C2H2-ZFPs in B. napus will enhance our understanding of the BnaQ-type C2H2-ZFP gene family and provide valuable insights for further functional investigations of BnaC09g35160D. Full article

The β-glucosidases (BGLUs) of Glycoside Hydrolase Family 1 (GH1) exhibit essential functions in plant secondary metabolism and stress responses, mediated by their dual catalytic capabilities in hydrolysis and transglycosylation. This study identified 149 BGLU family members within B. napus (Brassica napus L.), which were systematically categorized into 10 distinct subgroups. Subsequent characterization encompassed detailed examination of their motif composition, chromosomal distribution, gene collinearity, selection pressure, and expression profiling. Transient overexpression of BnBGLU77 in N. benthamiana (Nicotiana benthamiana), combined with untargeted metabolomics analysis, revealed pronounced modulatory effects on the degradation and accumulation of β-glucosidic compounds, suggesting potential roles of the protein encoded by BnBGLU77 in metabolic homeostasis and stress response mechanisms. These experimental results first validated the bidirectional catalytic activity of a BGLU enzyme in B. napus, while simultaneously advancing fundamental understanding of BnBGLU gene functions and providing new insights for developing stress-resistant rapeseed cultivars through targeted genetic improvement. Full article

Soluble sugars are among the key components determining the flavor quality of rapeseed bolting. However, the potential regulatory network governing the biosynthesis of soluble sugars during the growth and development of rapeseed bolting remains largely unknown. In this study, the total soluble sugar and starch contents were measured at the seedling and bolting stages in 203 Brassica napus germplasms. Among them, the inbred lines No51 and No106 were identified as high- and low-sugar materials, respectively. A comparative analysis of the soluble sugar composition between these two extreme lines revealed that sucrose and glucose are the key metabolites contributing to differences in the soluble sugar content. A total of 36,893 differentially expressed genes (DEGs) were identified by transcriptomics, including 19,031 significantly upregulated genes and 17,862 downregulated genes. Metabolomics has identified 25 common and unique metabolites. The combined analysis of transcriptomics and metabolomics showed that differentially expressed genes and metabolites were mainly concentrated in starch and sucrose metabolism, galactose metabolism, and the interconversion of pentose and glucuronic acid. The expression patterns obtained by RNA seq and qRT PCR are highly consistent. A regulatory network related to soluble sugar synthesis and metabolism was constructed, leading to the identification of BnaC02G0100500ZS, BnaC02G0100700ZS, and BnaC02G0092700ZS as potential key genes involved in the regulation of soluble sugar biosynthesis. Full article

The Yangtze River Basin serves as the primary rapeseed-producing region in China, accounting for over 80% of the national output, yet it is severely impacted by waterlogging, resulting in yield reductions of 17–42.4%. This study investigated the effects of pelleting treatments on growth and waterlogging resistance in Brassica napus varieties Xiangzayou 787 and Fanmingyoutai. Conventional pelleting agents were augmented with waterlogging resistance agents, surfactants, and amino acids as growth-promoting reagents. The results demonstrated that melatonin at $5.0\times {10}^{-5}$ mol/L significantly enhanced rapeseed growth and stress resistance. Specifically, for Xiangzayou 787, root fresh weight increased by 16.9% and stem diameter by 30.6%; for Fanmingyoutai, stem diameter increased by 16.9% and leaf length by 12.3%. The freezing injury index decreased by 90.9% for Xiangzayou 787 and 50% for Fanmingyoutai. The waterlogging injury index was reduced by 43.5% for Xiangzayou 787 and 30.4% for Fanmingyoutai, with stem diameter increasing by 30.6% and 16.5% in the respective varieties. The disease index decreased by 63.2% for Xiangzayou 787 (incidence reduced to 20.5%) and up to 57.1% for Fanmingyoutai (incidence reduced to 23.3%). Under this treatment, soluble protein content in Fanmingyoutai reached 20.37%, representing a 20.37% increase relative to the control. Peroxidase (POD) and superoxide dismutase (SOD) activities exceeded control levels, exhibiting an initial rise followed by a decline; malondialdehyde (MDA) content gradually increased; catalase (CAT) activity and soluble protein content showed an initial increase then decrease. The increase in relative electrical conductivity was reduced by 20.8% for Xiangzayou 787 and 17.3% for Fanmingyoutai. Yield per plant increased by 10.2% for Xiangzayou 787 and 35.6% for Fanmingyoutai. The newly developed pelleting formulation integrates waterlogging resistance agents, surfactants, and amino acids, unlike traditional agents, and proves effective for both hybrid and conventional rapeseed varieties. It enhances waterlogging resistance, promotes growth, improves disease resistance, and elevates seed quality while being cost-effective and simple for production and field application. This approach significantly boosts yield and supports productivity enhancement in southern rice fields, thereby improving rapeseed output and oil supply. Full article

Accurate prediction of chlorophyll content in Brassica napus L. (rapeseed) is essential for monitoring plant nutritional status and precision agricultural management. The current study focuses on single cultivars, limiting general applicability. This study used unmanned aerial vehicle (UAV)-based RGB and multispectral imagery to evaluate six rapeseed cultivars chlorophyll content across mixed-growth stages, including seedling, bolting, and initial flowering stages. The ExG-ExR threshold segmentation was applied to remove background interference. Subsequently, color and spectral indices were extracted from segmented images and ranked according to their correlations with measured chlorophyll content. Partial Least Squares Regression (PLSR), Multiple Linear Regression (MLR), and Support Vector Regression (SVR) models were independently established using subsets of the top-ranked features. Model performance was assessed by comparing prediction accuracy (R² and RMSE). Results demonstrated significant accuracy improvements following background removal, especially for the SVR model. Compared to data without background removal, accuracy increased notably with background removal by 8.0% (R²p improved from 0.683 to 0.763) for color indices and 3.1% (R²p from 0.835 to 0.866) for spectral indices. Additionally, stepwise fusion of spectral and color indices further improved prediction accuracy. Optimal results were obtained by fusing the top seven color features ranked by correlation with chlorophyll content, achieving an R²p of 0.878 and an RMSE of 52.187 μg/g. These findings highlight the effectiveness of background removal and feature fusion in enhancing chlorophyll prediction accuracy. Full article

Soil salinization is a major constraint to global crop productivity, highlighting the need to identify salt tolerance genes and their molecular mechanisms. Here, we integrated mRNA and miRNA profile analyses to investigate the molecular basis of salt tolerance of an elite Brassica napus cultivar S268. Time-course RNA-seq analysis revealed dynamic transcriptional reprogramming under 215 mM NaCl stress, with 212 core genes significantly enriched in organic acid degradation and glyoxylate/dicarboxylate metabolism pathways. Combined with weighted gene co-expression network analysis (WGCNA) and RT-qPCR validation, five candidate genes (WRKY6, WRKY70, NHX1, AVP1, and NAC072) were identified as the regulators of salt tolerance in rapeseed. Haplotype analysis based on association mapping showed that NAC072, ABI5, and NHX1 exhibited two major haplotypes that were significantly associated with salt tolerance variation under salt stress in rapeseed. Integrated miRNA-mRNA analysis and RT-qPCR identified three regulatory miRNA-mRNA pairs (bna-miR160a/BnaA03.BAG1, novel-miR-126/BnaA08.TPS9, and novel-miR-70/BnaA07.AHA1) that might be involved in S268 salt tolerance. These results provide novel insights into the post-transcriptional regulation of salt tolerance in B. napus, offering potential targets for genetic improvement. Full article

Understanding the alterations to the shoot and root traits of rapeseed (Brassica napus) in response to salt stress is vital for improving its ability to thrive in saline-prone regions. This research aims to evaluate the responses of shoot and root traits of rapeseed at the vegetative stage under salt- and salicylic acid-induced stress in hydroponic culture. Five parents and ten F₃ segregants of rapeseed were subjected to three treatments: T1: control, T2: 8 dSm⁻¹ salt, and T3: 8 dSm⁻¹ salt + 0.1 mM salicylic acid at 21 days of age. Salinity stress significantly reduced the estimated root surface area by 54% compared to control, highlighting the plasticity of roots under stress. The simultaneous application of salt and SA did not alleviate the salinity stress, but rather reinforced the degree of stress and decreased the number of leaves, diameter of the main axis, chlorophyll content, and estimated root surface area by 18.5%, 15.4%, 38.8%, and 23%, respectively, compared to T2. The parental genotype M-245 followed by F₃ genotype M-232×M-223 accounted for the higher overall estimated root surface area. These results provide novel insights into the responses of root traits in rapeseed breeding lines under dual treatment, which hold promising implications for future rapeseed breeding efforts focused on sustainable rapeseed production. Full article

Global climate change is causing increasing fluctuations in winter temperatures, including episodes of warm conditions above 9 °C. Such events disrupt cold acclimation in plants and can induce deacclimation, reducing frost tolerance and altering, among other things, hormonal regulation. This study investigated hormonal and molecular changes associated with cold acclimation and deacclimation in oilseed rape (Brassica napus L.) cultivars Kuga and Thure. Plants were grown under different conditions: non-acclimated (17 °C for three weeks), cold-acclimated (4 °C for three weeks), and deacclimated (16/9 °C day/night for one week). Detailed hormone analysis included auxins, gibberellins, cytokinins, stress-related hormones, and the expression of hormone-related genes (BnABF2, BnAOS, BnARF1, BnARR6, BnICS1, BnRGA, and BnWRKY57). Hormone concentrations in leaves changed dynamically in response to deacclimation with increased amounts of growth-promoting hormones and decreased amounts of stress hormones. Additionally, alterations in gene expression during deacclimation, such as in BnABF2 and BnICS1, may function as protective mechanisms to help maintain or regain frost tolerance during reacclimation when temperatures decline again after the warm period. These findings improve the understanding of hormonal and molecular responses involved in the deacclimation of oilseed rape. Full article

The BAHD acyltransferase family plays a critical role in plant secondary metabolism by catalyzing acyl transfer reactions that are essential for synthesizing metabolites involved in environmental adaptation. However, systematic investigation of this superfamily in Brassica napus has not been reported. In this study, 158 BnaBAHD genes were identified by comprehensive analyses of evolutionary relationships, motif structures, chromosomal distribution, gene collinearity, and selection pressures, and these genes were phylogenetically classified into five clades harboring conserved catalytic domains (HXXXD and DFGWG). Transient overexpression combined with metabolomic profiling demonstrated that two homologous seed-specific Clade V members, BnaBAHD040 and BnaBAHD120, which exhibited elevated expression during late seed development, significantly enhanced the accumulation of acylated metabolites contributing to biotic/abiotic stress resistance. This study provides the first experimental validation of the catalytic functions of BAHD enzymes in B. napus, establishing a theoretical foundation for leveraging this gene family in genetic improvement to develop novel rapeseed cultivars with enhanced stress tolerance and yield. Full article

KNOX genes play crucial roles in cell-fate determination and body plan specification during early embryogenesis. However, the specific gene structure and functional differentiation of KNOXs in Brassica napus is still unclear. We investigated KNOX genes in Brassica rapa (B. rapa), Brassica oleracea (B. oleracea), and Brassica napus (B. napus), which are polyploidy models with genome triplication after Arabidopsis-Brassiceae divergence. In total, 15, 14, and 32 KNOX genes were identified in B. rapa, B. oleracea, and B. napus, respectively. Phylogenetic analysis classified BnKNOXs (B. napus) into three classes with conserved domain organization. Synteny analysis indicated that BnKNOXs family expansion during allopolyploidization was mainly due to whole-gene and segmental duplications. Cis-element, gene structure, and expression pattern analyses showed high conservation within the same group. RNA-seq and qRT-PCR results divided BnKNOXs into three classes with distinct expression patterns: Class I exhibited moderate and specific expression in buds and inflorescence tips; Class III showed specific low expression in seeds and stamens; while the second class showed expression in most tissues. Sub-cellular localization results showed that the three candidate genes from the three classes exhibited distinct subcellular localizations, with BnSTM-C and BnKNAT3a-A predominantly in the nucleus and BnKNATM1-A in the cytoplasm indicating different expression patterns. Collectively, these findings provide a foundation for further functional studies of BnKNOX genes in B. napus. Full article

Effective management of straw in rice (Oryza sativa L.)–rape (Brassica napus L.) rotation systems is essential for optimising resource efficiency and improving soil quality. This two-year study investigated the impact of seven straw treatment methods on soil organic carbon (SOC) dynamics. The treatments examined were as follows: (1) control (CK); (2) rice straw (SF); (3) rapeseed straw (YF); (4) rice-straw-derived biochar (SB); (5) rapeseed-straw-derived biochar (YB); (6) mixed straw (YSF); (7) mixed biochar (YSB). Soil properties, enzyme activities and carbon fractions were subsequently analysed. During the canola growing season, the application of rice straw biochar increased oxidisable carbon (ROC), dissolved organic carbon (DOC) and microbial biomass carbon (MBC) by 25.7%, 61.7% and 67.2%, respectively, compared to the control. Notably, SB was more effective than unprocessed rice straw (SF) at increasing SOC and ROC. Furthermore, SB demonstrated superior performance in enhancing ROC (56.4%), MBC (36.0%) and DOC (12.2%) compared to hybrid biochar (YSB). SB consistently exhibited a higher carbon accumulation trend than the rapeseed-derived treatments (YF, YB and YSB). The results of the study indicated that applying rice straw biochar during the oilseed rape growing season was effective in increasing variable carbon pools and soil organic carbon accumulation. Full article

Concerning rising salinity and declining freshwater supply in the U.S. Southern Great Plains, alternative crop production choices using marginal saline irrigation water are irresistible. The study investigated plant traits related to salt tolerance in greenhouse canola (Brassica napus L.) in 2022 and 2023. Spring and winter canola, including ten genotypes each, were evaluated at six salinity levels (0; control, 2, 4, 6, 8, and 8 dS m⁻¹ EC). Plant height, stem mass, leaf area, and specific leaf area (SLA) showed a negative linear response, while quadratic relationships were observed in biomass and leaf mass with increased salinity levels. Substantial negative salinity impacts on plant traits occurred at ≥6 dS m⁻¹ EC (p ≤ 0.01) except for SLA. Overall, winter canola genotypes: Athena, Ericka, CP320WRR, CP115W, and CP225WRR, and spring genotypes: Empire, Monarch, Profit, and Westar, were relatively more salt-tolerant than others. Spring canola showed greater salinity tolerance than winter canola. Salinity stress resulted in differential responses of greater leaf mass in winter canola but more efficient leaf area production in spring canola. SLA and stem mass were highly correlated with most parameters. Findings indicate SLA and stem mass are potential salt tolerance traits in canola and warrant further investigations and validation. Full article

Brassica napus is one of the most important oil crops. Rapid breeding of excellent genotypes is an important aspect of breeding. As a cutting-edge and reliable technique, genome-wide selection (GS) has been widely used and is influenced by many factors. In this study, ten phenotypic traits of two populations were studied, including oleic acid (C18:1), linoleic acid (C18:2), linolenic acid (C18:3), glucosinolate (GSL), seed oil content (SOC), and seed protein content (SPC), silique length (SL), days to initial flowering (DIF), days to final flowering (DFF), and the flowering period (FP). The effects of different GS models, marker densities, population designs, and the inclusion of nonadditive effects, trait-specific SNPs, and deleterious mutations on GS were evaluated. The results highlight the superior prediction accuracy (PA) under the RF model. Among the ten traits, the PA of glucosinolate was the highest, and that of linolenic acid was the lowest. At the same time, 5000 markers and a population of 400 samples, or a training population three times the size of an applied breeding population, can achieve optimal performance for most traits. The application of nonadditive effects and deleterious mutations had a weak effect on the improvement of traits with high PA but was effective for traits with low PA. The use of trait-specific SNPs can effectively improve the PA, especially when using markers with p-values less than 0.1. In addition, we found that the PA of traits was significantly and positively correlated with the number of markers, according to p-values less than 0.01. In general, based on the associated population, a GS system suitable for B. napus was established in this study, which can provide a reference for the improvement of GS and is conducive to the subsequent application of GS in B. napus, especially in the aspects of model selection of GS, the application of markers, and the setting of population sizes. Full article

This study investigated the effects of three land use patterns—rice (Oryza sativa L.)–rapeseed (Brassica napus L.) rotation (Rapeseed), rice–shrimp (Procambarus clarkii G.) rotation (Shrimp), and the conversion of paddy fields to forestland (Forestland)—on aggregate structure, nutrient content, and microbial diversity in rice soils in Chuandian Town, Jingzhou District, Jianghan Plain, central China. The results revealed that the Shrimp treatment significantly increased soil organic matter (SOM), available nitrogen (AN), and available phosphorus (AP) content in the surface soil (0–10 cm) while reducing soil bulk density and improving pore structure. Forestland exhibited higher aggregate stability in deeper soil layers (20–40 cm), particularly in the 0.053–0.25 mm size fraction. Microbial diversity analysis showed that bacterial richness (Chao1 index) and diversity (Shannon index) were significantly higher in the Shrimp and Rapeseed treatments compared to those in the Forestland treatment, with Proteobacteria and Chloroflexi being the dominant bacterial phyla. Fungal communities were dominated by Ascomycota, withfForestland showing greater fungal richness in deeper soil. Soil depth significantly influenced aggregates, nutrients, and microbial diversity, with surface soil exhibiting higher values for these parameters than deeper layers. Redundancy analysis indicated that SOM, AP, and pH were the key drivers of bacterial community variation, while fungal communities were more influenced by nitrogen and porosity. Path analysis further demonstrated that land use patterns indirectly affected microbial diversity via altering aggregate structure and nutrient availability. Overall, the Shrimp treatment outperformed others in improving soil structure and nutrient supply, whereas the Forestland treatment was more conducive to promoting aggregate stability in deeper soil. Land use patterns indirectly regulated microbial communities through modifying soil aggregate structure and nutrient status, thereby influencing soil ecosystem health and stability. This study provides a theoretical basis for the sustainable management of rice soils, suggesting the optimization of rotation patterns in agricultural production to synergistically enhance soil physical, chemical, and biological properties. Full article

Plant diseases caused by Rhizoctonia solani present a significant challenge in agriculture. While chemical pesticides remain a common control strategy, their use leads to health and environmental problems. In contrast, endophytic bacteria with plant growth-promoting (PGP) activity offer a promising, sustainable alternative. In this context, a novel endophytic Priestia megaterium strain, KW16, originated from the bluegrass (Poa pratensis L.), demonstrated distinct biocontrol potential against R. solani. in vitro assays showed that KW16 inhibited R. solani growth by up to 58%, primarily by releasing volatile compounds. In planta experiments further highlighted KW16′s ability to colonize oilseed rape internal tissues, significantly enhancing its growth and development. In the presence of the pathogen, KW16 abolished the negative impact of R. solani and promoted plant growth, increasing shoot and root biomass by 216% and 1737%, respectively, when compared to the plants grown in fungal-infested soil. Biochemical and genome analyses confirmed the strain’s metabolic versatility, resistance to biotic and abiotic factors, and a whole spectrum of PGP and biocontrol traits such as biofilm formation, production of phytohormones, and synthesis of lytic enzymes, siderophores, and volatiles, alongside its ability to survive in the presence of autochthonous soil microflora. These findings position KW16 as a potent biological alternative to synthetic fungicides, with significant potential for sustainable crop protection. Full article