Soil salinity critically impairs global rice productivity, necessitating the exploration of salt-tolerant genetic resources in wild rice (Oryza rufipogon). Here, we identified a C2H2 transcription factor, ST5, from wild rice using a chromosome segment substitution line population. Functional analysis reveals that ST5 negatively regulates rice salt tolerance. A 36-bp insertion in the ST5W promoter harbors two W-box motifs, transcription factor OsWRKY80 binds to this insertion and represses ST5W expression. This repression reduces ST5W expression, alleviating its negative regulation on the downstream genes OsCPK4, which are pivotal for maintaining Na+/K+ homeostasis under salinity stress. Notably, the ST5W allele is exclusively present in a few of O. rufipogon accessions and absent in all cultivated rice varieties. Field trials demonstrate ST5W significantly improves grain yield across diverse genetic backgrounds under saline field conditions. Our work provides both an underexploited genetic resource and molecular insights for breeding salt-tolerant rice varieties to address soil salinization challenges.

Soil salinity represents one of the most damaging abiotic stresses constraining rice (Oryza sativa L.) production globally. Although CCCH-type zinc finger proteins have emerged as important regulators of stress responses in plants, the molecular mechanisms by which individual members modulate salt tolerance are not yet fully elucidated. Here, we characterize SZF12, a rice CCCH-type zinc finger protein containing two C2HC motifs and one canonical CCCH motif, as a negative regulator of salt stress tolerance. SZF12 is localized to the nucleus, possesses transcriptional activation activity, and is induced by salt stress. CRISPR/Cas9-derived loss-of-function mutants (szf12-c1 and szf12-c2) displayed significantly enhanced salt tolerance at both seedling stage and reproductive stages, with higher survival rates, lower Na+ accumulation and Na+/K+ ratio under salt stress, and increased grain yield compared to wild-type Zhonghua 11 (ZH11), whereas SZF12-overexpressing lines (OE1 and OE2) exhibited reduced salt tolerance, retarded growth, and increased grain length. Transcriptomic analysis revealed that loss of SZF12 enables a more targeted stress-responsive transcriptional reprogramming, specifically activating ion transport genes and suppressing carbon metabolism genes under salt stress. Taken together, our findings identify SZF12 as a negative regulator of salt stress tolerance in rice that modulates the amplitude of stress-responsive gene expression, and underscore its value as a gene-editing target for breeding salt-tolerant varieties.

BackgroundAccurate genomic information in specific rice varieties is essential for functional gene mining and advancing molecular breeding. Bindao8 (BD8) is an elite Japonica rice variety with notable salt tolerance.ResultsThis study presents a near telomere-to-telomere (T2T) genome assembly of ‘BD8’, with a size of 384.2 Mb and contig N50 of 31.69 Mb. A total of 58,685 genes were identified, 95.93% (56,297) of which were functionally annotated. Phylogenetic analysis clarified the genetic background of this cultivar. Abundant structural variations were detected, and enrichment analysis of unique genes identified four enriched KEGG pathways, including amino sugar and nucleotide sugar metabolism (ko00520), which supplies UDP-glucose/UDP-glucuronate for cell-wall biosynthesis. To address BD8’s salt tolerance, time-course transcriptomic profiling was integrated with the genome, revealing two salt-specific gene clusters (347 and 607 genes) and five significantly enriched salt-responsive KEGG pathways. Notably, the amino sugar and nucleotide sugar metabolism pathway (ko00520) was commonly enriched in both BD8’s unique genes and salt-specific clusters, suggesting that cell-wall precursor supply is a constitutive and inducible component of BD8’s tolerance mechanism.ConclusionThe high-quality BD8 genome assembly will serve as a critical resource for rice functional genomics and genomics-driven molecular breeding. The integration of BD8’s genome with transcriptomic data highlights the amino sugar and nucleotide sugar metabolism pathway as a key target for improving salt tolerance in rice breeding programs.

Soil salinity poses a serious threat to rice production. The salt tolerance of rice at the germination stage is one of the major determinants of stable stand establishment, which is very important for direct seeding in saline soil. The complexity and polygenic nature of salt tolerance have limited the efficiency of discovering and cloning key genes in rice. In this study, an RIL population with an ultra-high-density genetic map was employed to investigate the salt-tolerant genetic basis in rice, and a total of 20 QTLs were detected, including a major and stable QTL (qRCL3-1). Subsequently, salt-specific DEGs from a comparative transcriptome analysis were overlaid onto annotated genes located on a stable QTL interval, and eight putative candidate genes were further identified. Finally, from the sequence alignment and variant analysis, OsCam1-1 was confirmed to be the most promising candidate gene for regulating salinity tolerance in rice. This study provides important information for elucidating the genetic and molecular basis of rice salt tolerance at the germination stage, and the genes detected here will be useful for improvements in rice salt tolerance.

Rice is one of the main food crops to guarantee the world's food security. Although rice is a semi-aquatic crop, long-term flooding stress can also inhibit growth and reduce yield and quality. Especially during the germination period, the germination rate of rice was inhibited by flooding stress, which resulted in the low emergence rate. Therefore, in this study, rice lines or cultivars with flood tolerance (C11) and flood sensitivity (KY60) were screened, and analyzed the response mechanisms during seed germination at different time points of waterlogging stress through transcriptome and metabolome sequencing. Compared with C11, waterlogging stress significantly inhibited the germination and coleoptile growth of KY60. Certain pathways, including plant hormones, energy metabolism, and carbohydrate metabolism, were identified as significantly involved in the flooding stress response in rice. The plant hormone-related DEGs (IAA, SAUR, ARF, LOX) and metabolites (IAA, JA, GA, and SA) were identified to up-regulate gene expression levels and significantly up-accumulate phytohormone content in C11 to resist waterlogging stress. However, the ABA signaling pathway-related genes (ZHD, PLY) and ABA content were decreased in C11 under submerged conditions. It is beneficial for C11 to promote seed germination and coleoptile elongation under flooding conditions. A total of 150 DEGs (AMY, PGLR) and 58 related compounds were identified as involved in the energy metabolism and carbohydrate metabolism of rice after flooding stress. Candidate key genes and metabolite compounds were identified by combined RNA-Seq and LC-MS/MS correlation network analysis. This study provided insights to explore the flood-tolerance mechanism of rice and laid the foundation for the cultivation of new varieties of flood-tolerance rice.

Auxin plays a crucial role in regulating root growth and development, and its distribution pattern under environmental stimuli significantly influences root plasticity. Under K deficiency, the interaction between K+ transporters and auxin can modulate root development. This study compared the differences in root morphology and physiological mechanisms of the low-K-tolerant maize inbred line 90-21-3 and K-sensitive maize inbred line D937 under K-deficiency (K+ = 0.2 mM) with exogenous NAA (1-naphthaleneacetic acid, NAA = 0.01 mM) treatment. Root systems of 90-21-3 exhibited higher K+ absorption efficiency. Conversely, D937 seedling roots demonstrated greater plasticity and higher K+ content. In-depth analysis through transcriptomics and metabolomics revealed that 90-21-3 and D937 seedling roots showed differential responses to exogenous NAA under K-deficiency. In 90-21-3, upregulation of the expression of K+ absorption and transport-related proteins (proton-exporting ATPase and potassium transporter) and the enrichment of antioxidant-related functional genes were observed. In D937, exogenous NAA promoted the responses of genes related to intercellular ethylene and cation transport to K-deficiency. Differential metabolite enrichment analysis primarily revealed significant enrichment in flavonoid biosynthesis, tryptophan metabolism, and hormone signaling pathways. Integrated transcriptomic and metabolomic analyses revealed that phenylpropanoid biosynthesis is a crucial pathway, with core genes (related to peroxidase enzyme) and core metabolites upregulated in 90-21-3. The findings suggest that under K-deficiency, exogenous NAA induces substantial changes in maize roots, with the phenylpropanoid biosynthesis pathway playing a crucial role in the maize root’s response to exogenous NAA regulation under K-deficiency.

垦香 48 是以武运粳 21 为母本、05-18 为父本杂交,在F2 代优选单株,经过连续 7 a单株系统选择选育而成的香稻新品种.该品种具有高产、稳产、抗条纹叶枯病、品质好、适应性强的特点.2016～2017年河北省水稻品种区域试验,2 a平均产量为10511.3 kg/hm2,较对照品种垦育38增产4.3％;2017年河北省水稻生产试验,平均产量为 9945.0 kg/hm2,较对照品种垦育 38 增产 3.5％.2017～2018 年国家水稻京津唐组区域试验,2 a平均产量为 9665.3 kg/hm2,较对照品种津原 45 增产 3.9％;2019 年国家水稻京津唐组生产试验,平均产量为9634.2 kg/hm2,较对照品种津原45增产4.5％.该品种稻米品质达到了国家优质3级米标准.2018年通过河北省农作物品种审定委员会审定(审定编号:冀审稻 20180002);2020年通过国家农作物品种审定委员会审定(审定编号:国审稻 20200044).适宜在北京、天津、山东东营、河北冀东及中北部一季春稻区的稻瘟病轻发区域种植.

干旱严重限制了高粱的生长发育,高粱苗期抗性是关键时期,筛选苗期抗旱强的品种对高粱产业的发展具有重要意义.本研究以18种不同高粱品种为材料,在室内进行正常灌溉和150 g/L PEG6000浇灌模拟渗透胁迫处理试验,测定根长、根鲜重、根干重、地上鲜种、地上干重、根冠比及叶绿素相关荧光参数等12个性状指标,采用主成分分析和隶属函数法综合分析方法,对其进行苗期抗旱性鉴定及抗旱指标筛选.结果表明,在PEG胁迫下,不同高粱品种的性状指标受到不同程度的影响,各指标之间存在一定程度的相关性.主成分为4个因子,主成分累计贡献率为90.871％.根干重、地上鲜重、根鲜重、Fv/Fm和地上干重是决定第一主成分的主要性状,贡献率为36.004％.供试高粱品种的综合得分为0.242～0.810,品种间差异较大.其中,抗旱性最强的品种为28B和101B,冀乡酿3号的抗旱性最差.此外,筛选出了根鲜重和地上鲜重2个可以作为评价高粱苗期抗旱性的主要性状指标.本研究结果为高粱抗旱育种提供了基础材料和理论支持.

重金属污染导致的食品安全问题对人类健康造成了严重的危害.随着高粱产业的扩大,了解酿酒高粱的重金属污染情况对高粱的生产应用具有重要意义.为了解酿酒高粱在生产过程中的重金属污染及变化情况,本研究使用Cadence 土壤重金属分析仪测定土壤样品的重金属含量,根据农用地土壤污染标准判定检测土壤样品无污染,进一步按照食品安全国家标准中的相应检测法对冀酿2号籽粒,所产基酒及酒糟进行总砷、镉、铬、铜、总汞、镍、铅、锌重金属含量测定,根据现有国家标准的限制值评价测定结果.结果表明,高粱籽粒、基酒及酒糟重均存在重金属污染,其中籽粒检出铜、镍、锌分别含2.66 mg/kg、0.26 mg/kg、22.20 mg/kg;基酒中含镍0.23 mg/kg;酒糟中除汞之外的重金属含量范围为0.11～13.30 mg/kg.采用单因子污染指数法评定污染情况发现,此次样品的超标程度为酒糟＞籽粒＞基酒＞土壤.高粱酿酒过程中的重金属污染超标情况属于非安全级别,亟待关注和解决.

The EPIDERMAL PATTERNING FACTOR (EPF) plays a crucial role in plant response to abiotic stress. While the EPF has been extensively studied in model plants such as Arabidopsis thaliana, there is a lack of research on identifying EPF genes in the whole sorghum genome and its response to drought stress. In this study, we employed bioinformatics tools to identify 12 EPF members in sorghum. Phylogenetic tree analysis revealed that SbEPFs can be categorized into four branches. Further examination of the gene structure and protein conservation motifs of EPF family members demonstrated the high conservation of the SbEPF sequence. The promoter region of SbEPFs was found to encompass cis-elements responsive to stress and plant hormones. Moreover, real-time fluorescence quantitative results indicated that the SbEPFs have a tissue-specific expression. Under drought stress treatment, most SbEPF members were significantly up-regulated, indicating their potential role in drought response. Our research findings establish a foundation for investigating the function of SbEPFs and offer candidate genes for stress-resistant breeding and enhanced production in sorghum.

Salinity is one of the most widespread abiotic stresses affecting rice productivity worldwide. Understanding the genetic basis of salt tolerance is key for breeding salt-tolerant rice varieties. Numerous QTLs have been identified to help dissect rice salt-tolerance genetic mechanisms, yet only rare genes located in significant QTLs have been thoroughly studied or fine-mapped. Here, a combination of linkage mapping and transcriptome profiling analysis was used to identify salt tolerance-related functional candidate genes underlying stable QTLs. A recombinant inbred line (RIL) population derived from a cross between Jileng 1 (salt-sensitive) and Milyang 23 (salt-tolerant) was constructed. Subsequently, a high-density genetic map was constructed by using 2921 recombination bin markers developed from whole genome resequencing. A total of twelve QTLs controlling the standard evaluation score under salt stress were identified by linkage analysis and distributed on chromosomes 2, 3, 4, 6, 8 and 11. Notably, five QTL intervals were detected as environmentally stable QTLs in this study, and their functions were verified by comparative transcriptome analysis. By comparing the transcriptome profiles of the two parents and two bulks, we found 551 salt stress-specific differentially expressed genes. Among them, fifteen DEGs located in stable QTL intervals were considered promising candidate genes for salt tolerance. According to gene annotations, the gene OsRCI2-8(Os06g0184800) was the most promising, as it is known to be associated with salt stress, and its differential expression between the tolerant and sensitive RIL bulks highlights its important role in salt stress response pathways. Our findings provide five stable salt tolerance-related QTLs and one promising candidate gene, which will facilitate breeding for improved salt tolerance in rice varieties and promote the exploration of salt stress tolerance mechanisms in rice.

Cadmium (Cd) pollution is a serious threat to plant growth and human health. Although the mechanisms controlling the Cd response have been elucidated in other species, they remain unknown in Sorghum (Sorghum bicolor (L.) Moench), an important C4 cereal crop. Here, one-week-old sorghum seedlings were exposed to different concentrations (0, 10, 20, 50, 100, and 150 μM) of CdCl2 and the effects of these different concentrations on morphological responses were evaluated. Cd stress significantly decreased the activities of the enzymes peroxidase (POD), superoxide dismutase (SOD), glutathione S-transferase (GST) and catalase (CAT), and increased malondialdehyde (MDA) levels, leading to inhibition of plant height, decreases in lateral root density and plant biomass production. Based on these results, 10 μM Cd concentration was chosen for further transcription and metabolic analyses. A total of 2683 genes and 160 metabolites were found to have significant differential abundances between the control and Cd-treated groups. Multi-omics integrative analysis revealed that the flavonoid biosynthesis pathway plays a critical role in regulating Cd stress responses in sorghum. These results provide new insights into the mechanism underlying the response of sorghum to Cd.

The extensive use of herbicides has raised concerns about crop damage, necessitating the development of effective herbicide safeners. Fluxofenim has emerged as a promising herbicide safener; however, it's underlying mechanism remains unclear. Here, we screened two inbred lines 407B and HYZ to investigate the detoxication of fluxofenim in mitigating metolachlor damage in sorghum. Metolachlor inhibited seedling growth in both 407B and HYZ, while, fluxofenim could significantly restore the growth of 407B, but not effectively complement the growth of HYZ. Fluxofenim significantly increased the activities of glutathione-S-transferase (GST) to decrease metolachlor residue in 407B, but not in HYZ. This implys that fluxofenim may reduce metolachlor toxicity by regulating its metabolism. Furthermore, metolachlor suppressed AUX-related and JA-related genes expression, while up-regulated the expression of SA-related genes. Fluxofenim also restored the expression of AUX-related and JA-related genes inhibited by metolachlor and further increased expression of SA-related genes. Moreover, we noted a significant increase in the content of trans-zeatin O-glucoside (tZOG) and Gibberellin1 (GA1) after the fluxofenim treatment. In conclusion, fluxofenim may reduce the injury of herbicide by affecting herbicide metabolism and regulating hormone signaling pathway.

提高农业科研院所科研档案管理水平,是实现农业科研管理现代化的内在要求.文章以河北省农林科学院滨海农业研究所为研究样本,阐述了现阶段科研档案管理现状和存在的突出问题,从档案管理的顶层设计、档案管理人才培养、档案管理信息化建设、档案开发利用等方面提出了加强农业科研档案管理的建议,以期为农业科研院所提升科研档案管理水平提供参考.

Bindao-20 is a mid-late ripe japonica rice variety grown by Institute of Coastal Agriculture, Hebei Academy of Agriculture and Forestey Sciences. It has the characteristics of salt tolerance, high quality and yield. The rice quality has reached the national standard grade 3 and the salt tolerance grade 3. The average yield was 756.4 kg/667 m~2 in regional experiment of rice of Hebei Province, which was 14.6% higher than that of the control variety Kenyu-38, and 737.8 kg/667 m~2 in the production test, which was 14.9% higher than that of Kenyu-38. It was approved by Hebei Provincial Crop Variety Certification Committee in 2022 and is suitable for planting in Tangshan City, Qinhuangdao City and other places south of the Great Wall of Hebei Province as one season rice transplanting. It has been listed as the leading rice variety in 2023 by Qinhuangdao City.

为探明玉米花生带状间作模式下植株氮吸收利用和土壤微生物群落特征,设置玉米单作(SM)、花生单作(SP)和玉米花生间作(IMP)三种种植模式,系统分析了不同种植模式下氮素吸收利用规律,并采用16S/ITS测序技术明确玉米花生带状间作系统下根际土壤细菌/真菌群落结构变化.结果表明,间作玉米边行优势明显,地下和地上部干物质积累量和氮积累量显著高于单作玉米和间作玉米中间行.间作玉米和间作交互区根际土壤细菌和真菌多样性和丰富度降低,而间作花生根际真菌多样性和丰富度增加,其中变形菌门、担子菌门、子囊菌门等有益菌最为显著富集.土壤中细菌和真菌存在复杂的相关性,变形菌门与子囊菌门正相关.间作丰富了物种功能多样性,参与氨基酸运输、代谢和碳水化合物代谢的细菌和腐生营养型真菌的显著富集,改善了植物养分吸收,促进了植株生长发育.可见,玉米花生间作可通过优化土壤微生物的群落结构,促进植株对氮素的吸收和利用,本研究为玉米花生带状间作氮营养互促吸收提供了科学依据.

Potassium (K+) deficiency is a key factor limiting maize growth and yield. Auxin plays an important role in maize adaptation to K+ deficiency, but its physiological and molecular mechanisms are largely unclear. In this study, the exogenous application of 0.01 μmol·L–1 α-Naphthalene acetic acid (NAA) could effectively alleviate the growth inhibition of maize roots caused by K+ deficiency, especially in the low-K-sensitive maize inbred line D937. The transcriptome results showed that 3924 and 5458 genes were differentially expressed by exogenous NAA in D937 (sensitive to K+ deficiency) and 90-21-3 (tolerant to K+ deficiency) under K+ deficiency, respectively. The exogenous application of NAA to D937 results in maintenance of the indole acetic acid (IAA) levels by inducing an upregulation in the expression of YUCCA-encoding genes and decreases abscisic acid (ABA) content by inducing the differential expression of genes encoding NCED (downregulated), ABA2 (downregulated), and PP2C (upregulated), thereby reducing growth damage caused by K+ deficiency. In 90-21-3, exogenous NAA can decrease ABA content and increase IAA/ABA by inducing the differential expression of CYP707- and ABF-related genes, inhibiting the excess accumulation of reactive oxygen species by inducing the differential expression of genes encoding antioxidant enzymes, and maintain cellular K+ homeostasis by regulating the expression of genes encoding K+ channels and transporters, thus enhancing plant tolerance to K+ deficiency. This study lays the foundation for understanding the molecular mechanisms underlying maize adaptation to K+ deficiency.

为提高冀东稻区水稻抗稻瘟病育种水平,对157份粳稻资源通过田间诱发感病鉴定其稻瘟病抗性,并利用12个抗病基因标记进行基因型鉴定.结果表明,157份粳稻资源中表现为抗、中抗、中感、感及高感材料分别为2、70、64、9、12个,其中,材料ZY1和ZY2表现为抗.Piz和Pid3这两个抗病基因出现频率最高,而Pigm、Pia、Pita、Pik和Pi5在本地区对稻瘟病的抗性上起到主效作用,且聚合越多抗性基因,抗病性越高.结合种质资源农艺及产量性状,发现ZY2、ZY13、ZY15和ZY21适合作为抗稻瘟病育种的亲本.

为了解抗除草剂水稻与常规水稻对咪唑啉酮类除草剂的耐药性差异以及探索一种针对抗除草剂水稻育种过程中快速筛选杂交后代抗性材料的方法.通过配制不同浓度的咪唑乙烟酸溶液对抗除草剂水稻品种滨稻K1及常规水稻品种垦育60的根与叶片喷施后,测量计算其生长率及浸种后计算种子出苗率.结果表明,常规水稻的根和叶片的生长率及出苗率随着咪唑乙烟酸溶液浓度的提高迅速降低,并在较低浓度下停止生长和出苗;抗除草剂水稻的根和叶片的生长率及出苗率随着咪唑乙烟酸溶液浓度的提高先缓慢均匀降低,达到较高浓度后快速下降直至停止生长和出苗.分析数据得出抗除草剂水稻的种子、根和叶片对除草剂的耐药能力分别是常规水稻的20、90、15.7倍,抗除草剂水稻种子、根和叶对除草剂的耐力极限浓度分别为1.000％、0.900％、1.100％,2种水稻的不同部位间的耐药能力均为叶片＞种子＞根;利用0.03％咪唑乙烟酸溶液浸种72 h,或用0.07％咪唑乙烟酸溶液在水稻3叶1心期进行叶面喷施,可快速杀死全部不具有除草剂抗性的后代材料.

【Objectives】Premature senescence is often occurred in K-deficient soil, which seriously inhibites the yield of maize. In the study, the premature senescence of maize caused by K deficient stress was studied from root morphology, structure and activity after flowering stage.【Methods】Pool experiment was conducted using maize inbred line of K-tolerant 90-21-3 and K-sensitive D937 as tested materials. Both maize lines were grown 植物营养与肥料学报 2021, 27(2): 301–311 doi: 10.11674/zwyf.20235 Journal of Plant Nutrition and Fertilizers http://www.plantnutrifert.org