Glyphosate is currently the most widely used broad-spectrum herbicide.Cultivating glyphosate tolerant crops will help improve the effectiveness of chemical control on weed in farmlands,reduce the use of pesticide,and simplify preventive and control measures.To fully detect the glyphosate tolerance(GT)loci in wheat,484 germplasm resources from the Huang-huai wheat region were used to identify glyphosate toxicity.Based on the wheat 15K SNP array data,genome-wide association analysis(GWAS)was used to explore QTL related to glyphosate tolerance in wheat.The main results were as follows:the trend of changes in glyphosate tolerance of wheat varieties cultivated in different eras was slow,and the glyphosate tolerance had not significantly improved;three glyphosate tolerant wheat germplasms(including Henong 130,Jimai 782 and Taishan 23)were selected based on the phenotypic identification results of pesticide damage;seven QTL associated with the level of wheat pesticide damage were detected by GWAS,including 19 significant SNPs,distributed on wheat chromosomes 1A(0.00—30.48 Mb),1B(6.57—30.57 Mb),1D(0.00—22.98 Mb),4A(656.09—680.09 Mb),5A(508.19—532.19 Mb),6A(54.56—85.09 Mb),and 6D(12.02—36.02 Mb);the two QTL qGlyT-1A and qGlyT-6A located on wheat chromosomes 1A and 6A were the main effector sites for glyphosate tolerance in wheat,containing a total of 16 genes that may be related to glyphosate tolerance in wheat.

To explore the effects of nitrogen application rate on nitrogen uptake and translocation characteristics,nitrogen use efficiency,and the formation mechanisms of yield and quality in soft wheat under weak light stress during the after anthesis stage,under pot conditions,the soft wheat variety Quanmai 725(QM725)was used as the material,and the ¹⁵N tracer method was used.Two nitrogen rates were set in the experiment,namely N1(N 120 kg/ha),N2(N 180 kg/ha),and two shading treatments were set at the wheat filling stage(7-35 d after anthesis)under each nitrogen application rate,namely CK(no shading),SH(30% shading).The relationship between nitrogen application rate and grain yield and quality of soft wheat under weak light after anthesis was analyzed,and the effects of different nitrogen application rates on nitrogen accumulation,transport,grain yield and quality of soft wheat under weak light after anthesis were studied.The results showed that compared with the control,under the conditions of N1 and N2,the nitrogen accumulation of plants at flowering stage and vegetative organs at maturity stage was significantly reduced by weak light treatment after anthesis,and the proportion of nitrogen from fertiliser was significantly higher than that from soil nitrogen,while the proportion of nitrogen accumulation in grains at maturity stage from soil nitrogen was significantly higher than that from fertiliser nitrogen.Under the same nitrogen application rate,the proportion of basal nitrogen fertiliser was greater than that of topdressing nitrogen fertiliser.Under the same weak light treatment conditions,compared with N1,N2 increased the accumulation of fertiliser nitrogen at flowering stage,the accumulation of total nitrogen and fertiliser nitrogen at maturity stage,and the accumulation of total nitrogen,fertiliser nitrogen and soil nitrogen at maturity stage.Under N1 and N2 treatments,the nitrogen harvest index,nitrogen harvest index,nitrogen production efficiency,grain number per spike,1000-grain weight and grain yield of wheat decreased significantly with the decrease of light intensity after anthesis.The content and accumulation of protein and starch in soft wheat grains increased significantly with the increase of nitrogen fertilizer.However,under the same nitrogen application rate,weak light stress reduced the starch content,protein and starch accumulation in grains.Weak light stress after anthesis significantly affected the nitrogen accumulation of soft wheat plants,reduced the transport efficiency of storage substances from vegetative organs to grains after anthesis,resulting in a decrease in the contribution rate of vegetative organs to grains,which was not conducive to the overall nitrogen transport efficiency of plants.With the increase of nitrogen application rate,the nitrogen harvest index,nitrogen harvest index,nitrogen production efficiency and nitrogen use efficiency of wheat were significantly improved.Under the same nitrogen application rate of N1 and N2,after anthesis weak light stress significantly reduced the accumulation of protein and starch in soft wheat grains,which in turn affected the formation of grain weight,resulting in a decrease in yield.

The ubiquitination pathway is one of the key signaling pathways in response to drought stress.In order to clarify the biological function of E3 ubiquitin ligase TaSINA101 gene in response to drought stress,the TaSINA61,TaSINA101 and TaSINA105 genes were cloned from JM47,an excellent drought-resistant wheat cultivar,and their sequence characteristics were analyzed by bioinformatics methods,and the expression levels of the three genes in wheat roots and leaves were detected by qRT-PCR under PEG-6000,NaCl,low temperature and ABA treatments.The heterologous expression of TaSINA101 in transgenic rice was used to analyze the biological function of TaSINA101 in response to drought stress.The results showed that the TaSINA61,TaSINA101 and TaSINA105 genes contained one intron and two exons,and the encoded proteins were composed of 282 amino acids.The qRT-PCR expression analysis showed that the expression of these three genes was induced by various abiotic stresses such as drought stress in roots and leaves.Phenotypic analysis of TaSINA101 transgenic rice under drought stress showed that the leaf fresh weight and dry weight, maximum root length, average root diameter and leaf relative water content of transgenic rice lines OE-1, OE-2 and OE-3 were significantly lower than those of wild type,while the relative conductivity of leaves of transgenic rice lines OE-1 and OE-2 was significantly higher than that of wild type.Therefore,TaSINA101 negatively regulates drought stress tolerance in rice.This study provides a basis for in-depth analysis of the biological function of TaSINA101 gene in wheat.

To clarify the regulatory effect of nitrogen(N)fertilizer reduction and postponing on the productivity of wheat-maize double cropping system in Huang-Huai-Hai Plain.The annual N fertilizer experiment of summer maize and winter wheat was established of four N application systems:annual N fertilizer application 400 kg/ha of traditional farmer treatment(F₄₀₀),10% reduction of annual N fertilizer(FN),20% reduction of annual N fertilizer(FH),and 30% reduction of annual N fertilizer(FL)from 2020 to 2023 at Jiyang Experimental Base of the Shandong Academy of Agricultural Sciences in Jinan.The grain yield,aboveground N accumulation characteristics,N use efficiency,and the nitrate residue after harvest in the 0—200 cm soil layer of wheat-maize double cropping system were tested,in order to provide the theoretical basis for further optimization of N fertilizer management in Huang-Huai-Hai Plain.The results indicated that N fertilizer postponing was optimized the grain yield of summer maize and winter wheat under the condition of N reduction,and the averaged across the three years,FL significantly increased by 9.2%—18.1%,13.5%—20.5%,and 11.1%—19.1%,respectively,compared with F₄₀₀ and FN.N fertilizer postponing improved the N accumulation rate,and promoted aboveground N accumulation at wheat-maize different growth stages,and the averaged across the three years,FL significantly increased plant N accumulation by 5.7%—12.3% and 5.0%—12.8% under silking and maturity,respectively,compared with F₄₀₀,FN,and FH,as well as 8.2%—17.2% in grain N accumulation.For winter wheat,FL and FH treatments were significantly higher than F₄₀₀ and FN at jointing,anthesis,and maturity,and the averaged across the three years,FL and FH significantly increased by 23.4%—28.1%,20.7%—26.3%,and 12.6%—20.8%,respectively,compared with F₄₀₀,FN and FH,at the same time the grain N accumulation under FL significantly increased by 16.4%,15.0% and 5.8%,respectively,compared with F₄₀₀ and FN.N fertilizer postponing optimized the N use efficiency of wheat-maize double crop system,the averaged across the three years,FL significantly increased N uptake efficiency by 4.8%—57.7% and 32.0%—72.4% of summer maize and winter wheat,respectively,compared with F₄₀₀,FN,and FH;and FL significantly increased N partial factor productivity by 68.8% and 40.4% in summer maize,respectively,compared with F₄₀₀ and FN,as well as by 38.4%—71.8% in winter wheat compared with F₄₀₀,FN,and FH.At harvest of summer maize and winter wheat,the soil nitrate residue was mainly enrichment in the 0—40 cm soil layer under four N application systems,the averaged across the three years,accounted for 40.0%,38.9%,44.9%,42.5% and 37.3%,36.9%,46.7%,38.3% of the 0—200 cm soil layer,respectively.In addition,the obvious accumulated effects in 0—200 cm soil layer nitrate residue under F₄₀₀ and FN treatments at harvest of summer maize and winter wheat,but there was the relative balance was achieved under FL and FH treatments.In conclusion,a 30% reduction of annual N fertilizer by N fertilizer postponing could optimize plant N accumulation characteristics and realized synergistic improve grain yield and N use efficiency.Therefore,FL treatment was an optimal N application system for realizing the collaborative target of high-yield,high-efficiency,and environment-friendly of wheat-maize double cropping system in Huang-Huai-Hai Plain.

The effects of different degrees of drought stress on antioxidant enzyme activity, malondialdehyde(MDA)content,photosynthetic characteristics,and yield composition of wheat were investigated to provide a theoretical basis and technical support for optimizing water-saving production of wheat.From 2023 to 2025,four soil water gradients of heavy drought(I-hd),moderate drought(I-md),mild drought(I-fd)and suitable water content(I-sm)were set up in the Longkou Experimental Station of Shandong Academy of Agricultural Sciences.The antioxidant enzyme activity,MDA content,photosynthetic characteristics and grain yield composition of wheat under different drought stress were systematically analyzed.The results showed that compared with moderate and heavy drought,mild drought and suitable water were beneficial to optimize spike number,grain number per spike and 1000-grain weight,thus significantly increasing grain yield,and the average grain yield in two years increased by 11.1%—51.0%.The activities of antioxidant enzymes such as superoxide dismutase(SOD),peroxidase(POD),and catalase(CAT)were significantly increased at each growth stage under mild drought and suitable water,and the MDA content in leaves was significantly decreased at each growth stage,which played an important role in reducing the degree of cell membrane lipid oxidation and delaying plant senescence.The leaf area index(LAI),chlorophyll relative value(SPAD value)and net photosynthetic rate(Pn)of leaves at booting,flowering and mid-filling stages were maintained at a high level under mild drought and suitable water conditions,which provided a physiological basis for the improvement of photosynthetic rate,while the above indices were significantly reduced during the whole growth period under moderate and severe drought conditions.The results of correlation analysis showed that the activities of antioxidant enzymes(SOD,POD,CAT)were significantly negatively correlated with MDA content,and significantly positively correlated with photosynthetic characteristics(LAI,SPAD,Pn)and yield components(spike number,grain number per spike,1000-grain weight),which provided physiological guarantee for maintaining higher photosynthetic capacity.In summary,both mild drought and suitable water significantly increase the activities of antioxidant enzymes such as SOD,POD,and CAT in leaves at each growth stage,reduce the content of harmful substances such as MDA,and optimize LAI and SPAD values to improve the photosynthetic rate of leaves.The final grain yield increased by 11.1%—51.0%.However,there was no significant difference in grain yield,antioxidant enzyme activity and photosynthetic characteristics between mild drought and suitable water.Therefore,it is concluded that under mild drought conditions,high and stable yield of wheat can be achieved by optimizing photosynthetic characteristics and leaf antioxidant capacity,which provides a reliable practical approach for water-saving crop production.

To clarify the effects of drought stress and cultivars on the net photosynthetic rate(Pn),the activities of photosynthetic enzymes in flag leaf in the afternoon(FLA)during grain filling stage and grain yield of winter wheat,a pond culture experiment with four water levels and two winter wheat cultivars was conducted under the condition of rainproof pond cultivation in 2019—2021.The four water treatments included severe drought(W1),moderate drought(W2),mild drought(W3),and suitable water supply(W4).The Pn,and the activities of Rubisco,RCA,PEPC,ATPase and PPDK in flag leaf from 14:00 to 16:00 during the early(EGFS)and medium(MGFS)grain filling stage,and the grain yield at maturity of strong drought resistance cultivar Jinmai 47(JM47)and weak drought resistance cultivar Yanzhan 4110(YZ4110)were investigated.Drought stress decreased the FLA Pn and activities of most photosynthetic enzymes,and the grain yield of wheat.The decrease of these indexes increased with drought stress degree,but the effects were different among varieties and years.Compared with W4,the FLA Pn of JM47 under W1,W2 and W3 decreased by 33.6%—40.6%,12.0%—30.5% and 5.0%—13.5%,as well as YZ4110 decreased by 44.0%—52.0%,22.5%—38.1% and 11.5%—20.5%,respectively.Compared with W4,the FLA Rubisco activity decreased during EGFS but increased during MGFS for JM47,while it decreased by 13.3%—25.6%,7.1%—14.0% and 11.2%—11.6% for YZ4110,respectively,under W1,W2 and W3.Compared with W4,the FLA RCA activity significantly decreased under most drought treatments during EGFS,while increased under W2 and W3 for JM47 and decreased under W1 and W2 for YZ4110 during MGFS.Compared with W4,the FLA ATPase activity of JM47decreased under W1 but increased under W3,while that of YZ4110 decreased under W1,W2 and W3 by 19.3%—48.7%,7.2%—24.2% and 0.1%—8.9%,respectively.The FLA PEPC activity under different treatments varied with growing seasons and varieties.Compared with W4,the FLA PPDK activities of JM47 and YZ4110 under W1 were decreased by 12.4%—18.8% and 16.7%—18.2%.Compared with YZ4110,in most conditions,the FLA Pn and photosynthetic enzyme activities of JM47 had no significant difference under suitable water supply(W4),but increased under drought treatments(W1,W2 and W3).The results of correlation analysis showed that yield,FLA Pn were significantly positively correlated to FLA ATPase activity during EGFS and MGFS,as well as FLA PEPC activity during EGFS.Thus,increasing the FLA ATPase and PEPC activities during the grain filling period is conducive to the increase of FLA Pn and grain yield of wheat.

To elucidate the mechanisms of cold response and explore superior cold-tolerance gene resources in wheat,this study employed transcriptome sequencing to uncover key regulatory networks underlying wheat cold response,and performed functional validation of the candidate gene TaGGCT18-6A.The results demonstrated that 4 ℃ cold treatments induced 10 893 and 18 784 differentially expressed genes(DEGs)in wheat seedlings after 6 h and 24 h cold treatment,respectively.KEGG analysis revealed significant enrichment of DEGs in pathways including MAPK signaling transduction and glutathione metabolism.A γ-glutamyl cyclotransferase gene TaGGCT18-6A was cloned through screening key genes in glutathione metabolism.This gene had a length of 1 772 bp,encoding 218 amino acids with conserved GGCT-like superfamily and ChaC core domain.Promoter cis-acting element analysis identified stress-responsive elements such as low-temperature-responsive(LTR)and dehydration-responsive (DRE)elements; consistently,expression pattern analysis showed sustained upregulation of TaGGCT18-6A under 4 ℃ cold treatments. Functional validation in transgenic rice revealed that overexpression lines OE#1, OE#2 and OE#3 exhibited significantly enhanced survival rate,plant height,and biomass. Overexpression lines OE#1 and OE#2 exhibited significantly enhanced plant height, while overexpression lines OE#1, OE#2 and OE#3 exhibited significantly reduced relative electrolyte leakage under -4 ℃ freezing treatments.After 4 ℃ treatment,overexpression lines accumulated higher levels of osmolytes(proline and soluble sugars),decreased malondialdehyde(MDA)content,and increased activities of superoxide dismutase(SOD),peroxidase(POD),and catalase(CAT).These findings collectively demonstrated that TaGGCT18-6A enhanced plant cold tolerance by regulating glutathione metabolism to improve antioxidant capacity.This study will provide a theoretical foundation and valuable genetic resources for molecular breeding of cold-tolerant wheat.

In order to explore the effects of mulching measures(such as straw returning and plastic film mulching)on soil aggregates and organic carbon in semi-arid rain-fed agricultural areas.The potato-wheat rotation system in the dryland of Longzhong was used as the research object.The effects of straw stubble mulching(SR),straw strip mulching(SM),plastic film mulching(PM)and open field(CK)on soil organic carbon components(SOC,POC,MAOC),aggregate stability and aggregate carbon contribution rate were systematically analyzed.By evaluating the soil improvement effect of different mulching measures,integrating the intrinsic indicators such as soil organic carbon component dynamics,aggregate stability and crop productivity and water use efficiency data reported in the literature,the optimal mulching mode that can synergistically improve organic carbon and aggregate stability was screened.The results showed that the organic carbon content and aggregate stability of potato and wheat were improved by three mulching measures in potato-wheat rotation,and the effect of SR treatment was the best.Compared with CK treatment,the SOC content of SR and SM treatment increased by 15.38% and 7.78%,and the SOC content of PM treatment did not change significantly.SR and SM treatment increased the POC content in 0—20 cm soil layer by 18.54%,16.62%,and PM decreased the POC content in 0—20 cm soil layer by 3.06%.The overall trend of MAOC increased in each treatment was SR>SM>PM>CK.Compared with CK treatment,SR and SM treatments increased the proportion of MWD,GMD,>2 mm aggregates and SOC content,while PM significantly reduced MWD and GMD.SR increased the SOC enrichment coefficient of>2 mm aggregates by 17.26% in 0—20 cm soil layer,and SR and SM treatments significantly increased the SOC contribution rate of>2 mm aggregates.In summary,under the conditions of this experiment,all three mulching measures can increase soil organic carbon content,and straw stubble mulching returning to the field has the best effect in improving soil organic carbon content and aggregate stability,effectively improving soil fertility.

To investigate the responses of different types of wheat to various nitrogen-phosphorus-potassium ratio compound fertilizers in the Huaihe River region,in terms of photosynthetic characteristics,dry matter accumulation and distribution,yield and quality,four wheat varieties(Zhongke 166,Yannong 999,Huaimai 43,Shannong 17)were selected as experimental materials.Two types of compound fertilizers were set up:high-nitrogen compound fertilizer(N-P₂O₅-K₂O=26-13-7)and equal-proportion compound fertilizer(N-P₂O₅-K₂O=18-18-18).The effects of different compound fertilizer treatments on the photosynthetic characteristics,dry matter accumulation and distribution,yield and quality of each wheat variety were analyzed.The results showed that compared with the equal-proportion compound fertilizer,the high-nitrogen compound fertilizer significantly increased the LAI,SPAD value,net photosynthetic rate and photochemical efficiency of the four varieties,delayed leaf senescence,and prolonged photosynthetic time;it also increased the dry matter accumulation at the flowering and maturity stages,optimized the dry matter distribution ratio,and ultimately increased the grain yield by 4.5% to 14.9%,with protein and wet gluten contents increasing by 1.36% to 8.17% and 3.55% to 9.36% respectively.The response of different varieties to the high-nitrogen compound fertilizer varied slightly,with Yannong 999 having the best overall performance,the largest increase in SPAD value and LAI,the highest net photosynthetic rate and yield,the highest dry matter distribution ratio at the maturity stage,and significant quality improvement;Zhongke 166 had the largest yield increase,the highest protein content and wet gluten content;Huaimai 43 had the highest increase in grain dry matter accumulation;Shannong 17 had the weakest response to the high-nitrogen compound fertilizer,but its yield was still 9.3% higher than that of the equal-proportion compound fertilizer.In summary,the high-nitrogen compound fertilizer showed significant advantages in the photosynthetic characteristics,dry matter accumulation and distribution,yield and quality of different types of wheat.Among them,Yannong 999 had the best overall performance.

To investigate the role of calcium-dependent protein kinase (CDPK) in wheat growth and stress response,the TaCDPK17 gene was cloned from common wheat and its sequence structure,expression pattern,and stress resistance function were preliminarily analyzed.The results showed that the length of the TaCDPK17 gene coding region was 1 701 bp, encoding 566 amino acids and possessing typical structural features of the CDPK family, including one conserved serine/threonine kinase domain and four EF hand shaped domains. Evolutionary tree analysis of TaCDPK17 and CDPK17 from 12 other plants showed that TaCDPK17 had high homology with the CDPK17 sequence of gramineous crops,especially Aegilops tauschii and barley.The promoter region of TaCDPK17 gene contained multiple cis regulatory elements related to hormone signaling pathways,light response.Among them, there are more abscisic acid (ABA) responsive elements (ABRE) and methyl jasmonate responsive elements (CGTCA). The expression analysis based on Real-time Fluorescence Quantitative PCR showed that the expression level of TaCDPK17 increased to varying degrees after induced by 100 μmol/L ABA, 100 μmol/L methyl jasmonate, 20% PEG6000, and 250 mmol/L NaCl. Under stress conditions of 2 μmol/L ABA and 100 mmol/L NaCl, the germination rate of Arabidopsis seeds overexpressing TaCDPK17 was significantly higher than that of the wild type. Meanwhile, overexpression of TaCDPK17 alleviated the inhibitory effects of ABA or osmotic stress treatments on seedling root growth. During stomatal closure, transgenic plants overexpressing TaCDPK17 are more sensitive to ABA and exhibit a stronger stomatal closure trend compared to wild-type plants. These results indicated that TaCDPK17 plays an important role in stress response and hormone signaling in wheat.

Although high-throughput KASP markers have been developed for the wheat quality subunit 7^OE,they are different from the KASP markers developed by SNP,the problem of not being able to effectively distinguish between homozygous and heterozygous remains.To clarify the issue of whether the 7^OE subunit is homozygous,this study used Jinqiang 6(containing 7^OE+8^* subunits)and Kenong 199(containing 7+9 subunits)and hybrid offspring as materials,and used the Waxy-D1 gene of wheat as an internal reference gene.The relative copy number of the 7^OE gene to the reference gene was detected by quantitative PCR using the universal dual-color fluorescence used in KASP markers to determine whether the 7^OE gene exists and whether it is homozygous,and the detection results were verified by a relevant molecular marker.The results showed that the relative copy number of the parent Jinqiang 6,with the 7^OE gene,was the highest,the relative copy number of the parent Kenong 199,without the 7^OE gene,was 0,and the relative copy number of their hybrid F₁ generation was intermediate,and the three types were easily separated.In its F₂ segregating population,the relative copy numbers of the 7^OE gene were also easily divided into high,medium and 0 three types.The genotypes that were detected as homozygous and heterozygous for the 7^OE gene were further detected by the PCR marker of the 9 subunit(which can detect 9 subunit and the 8^* subunit that are closely linked to the 7 subunit and the 7^OE subunit,respectively),and the results were completely consistent.The high-throughput 7^OE universal dual-color fluorescence quantitative PCR marker established in this study can accurately distinguish whether the 7^OE subunit is present,and whether it is homozygous,which has a positive effect on promoting the molecular marker-assisted selection of high-quality subunit 7^OE.

Fusarium head blight(FHB)is a devastating fungal disease that seriously threatens the safety of wheat production.Marker-assisted selection(MAS)and pyramiding of resistance genes represent efficient strategies for FHB-resistant breeding.To establish a high-throughput screening system for FHB resistance genes and enhance wheat resistance in Sichuan Province,we performed genome-wide genotyping using a 100K SNP array on 14 Sichuan wheat varieties(lines)along with three FHB-resistant genetic materials.Based on the reported genetic linkage intervals of major FHB resistance genes(Fhb2,Fhb4,Fhb5),we identified SNPs co-segregating with Fhb5 or linked to Fhb2,Fhb4,and subsequently developed kompetitive allele-specific PCR(KASP)markers.Results showed that the genetic relationship of 17 wheat varieties(lines)could be clustered into two major groups:two northern wheat-derived resistant materials(NMAS070 and NMAS069)formed an independent cluster distinct from the Sichuan varieties(lines)while the remaining 15 varieties(lines)were clustered together and subdivided into two subgroups.Functional gene profiling revealed FHB-resistant parents carried superior resistance loci,whereas agronomic parents harbored favorable alleles for yield and quality traits.Through SNP screening,we identified 8 critical SNPs within the linkage intervals of Fhb2,Fhb4 and the co-segregation region of Fhb5.These SNPs enabled the successful development of 4,2,and 2 high-specificity KASP marker systems for Fhb2,Fhb4 and Fhb5,respectively.Validation experiments confirmed all KASP markers achieved precise genotyping and were effectively implemented in molecular breeding for FHB-resistance.This study established a high-efficiency KASP marker system for Fhb2,Fhb4 and Fhb5,providing a robust technical platform for improving FHB resistance breeding of wheat varieties in Southwest China.

The hexameric Paf1 (RNA polymerase Ⅱ associated factor 1) complex is a crucial transcription regulator in eukaryotes.Paf1-regulated expression of specific genes in plants is closely related to diverse biological processes including growth,development,and stress responses.In order to get information on the responses of Paf1 to abiotic stresses in common wheat,homologous sequence searches were performed to identify all of the genes encoding each of the Paf1 subunits in the wheat genome.mCherry fusions of the wheat Paf1 subunit proteins were expressed in protoplasts and tobacco leaves for determination of protein subcellular localization by fluorescence microscopy.qRT-PCR assays were conducted to profile the expression of wheat Paf1 subunit genes in response to different abiotic stresses.The results showed that,in wheat,five of the Paf1 subunits,TaVIP3,TaVIP4,TaVIP5,TaVIP6,and TaPHP,were each encoded by one set of homeologous genes while the sixth subunit TaVIP2 was encoded by two sets.Plant VIP2 sequences had an N-terminal proline-rich region with variable length,and wheat TaVIP2 sequences had an additional glutamine-rich region.Protein subcellular localization assays revealed the nuclear localization of TaVIP2,TaVIP4,TaVIP5,and TaVIP6 proteins and the nuclear and cytoplasmic localization of TaVIP3 and TaPHP proteins.Gene expression analyses revealed similar tissue-dependent constitutive expression variations and similar stress-induced expression patterns of wheat Paf1 subunit genes.These genes coordinately responded to the stress of high temperature by expression upregulation and to the stresses of salt and drought by expression downregulation.Collectively,our results suggested the involvement of expression regulation of Paf1 subunit genes in the responses of wheat to abiotic stresses.

To elucidate the role of WRKY transcription factor family members in the dynamic regulation of wheat growth and development,as well as in responses to abiotic stresses,this study investigated the expression patterns of TaWRKY gene under drought,high salinity,and low-temperature stress conditions.Using the common wheat cultivar Chinese Spring as the experimental material,we obtained the TaWRKY70 gene through molecular cloning.The coding sequence of TaWRKY70 was 885 bp in length,encoding a 294-amino-acid hydrophilic and unstable protein.Bioinformatics analysis revealed that the protein possessed a typical WRKYGQK conserved domain and a C₂HC-type zinc finger structure,classifying it as a Group Ⅲ WRKY transcription factor.Cis-regulatory element analysis of the TaWRKY70 promoter region identified regulatory elements involved in responses to methyl jasmonate,abscisic acid,and ethylene.Co-expression gene analysis suggested that TaWRKY70 was associated with multiple stress response processes in wheat,including hormone signaling,defense against microbial pathogens,and responses to cold stress.Phylogenetic analysis indicated that TaWRKY70 shared a close evolutionary relationship with WRKY70 proteins from other Poaceae species,such as barley,maize,sorghum,and foxtail millet.Subcellular localization experiment further confirmed that TaWRKY70 was localized in the nucleus,consistent with the characteristics of a transcription factor.Expression pattern analysis showed that TaWRKY70 was expressed in wheat roots,stems,leaves,young spikes,and grains,with higher expression levels observed in roots and leaves.Under abiotic stress conditions,TaWRKY70 expression was downregulated in response to abscisic acid and low-temperature treatments but upregulated under salicylic acid,NaCl,PEG6000,and high-temperature treatments.In conclusion,the cloning of TaWRKY70 gene and analysis of its expression pattern provide a basis for the next step to analyze the molecular mechanism of TaWRKY70 involved in wheat stress resistance.

Tiller-related traits are important characteristics of wheat plant type,which determine plant structure and affect grain yield.In order to understand the inheritance and drought resistance of tiller-related traits in wheat under different water conditions,and to excavate the loci related to tiller-related traits,240 wheat varieties (lines) were selected as the subjects of this study,based on the phenotypic identification of tiller angle,effective tiller number and yield per unit area under normal irrigation (NI) and drought stress (DS) conditions,and the comprehensive evaluation of drought resistance,combined with 90K gene chip,genome-wide association study (GWAS) was to identify genetic loci for tiller-related traits and to screen for superior germplasm.The tiller angle,effective tiller number and yield per unit area showed significant difference,and the coefficient of variation ranged from 0.07 to 0.33.According to D-value,the drought resistance of Zhongyou 206 was the best.A total of 54 stable genetic loci significantly associated with tiller angle and other traits were detected, distributed on all chromosomes except 3D, 4D and 5D. Three identical stable loci were commonly detected under both treatments, located on chromosomes 2B, 4B, and 6B. Additionally, four pleiotropic loci were commonly detected in different traits, located on chromosomes 2B, 2D, and 5B.At the same time,the haplotype analysis of Ra_c491_902 (R²=5.45%—17.91%),which was significantly correlated with tiller angle on chromosome 2B,showed that there were three haplotypes:TA-Hap1,TA-Hap2 and TA-Hap3,the haplotypes (lines) containing TA-Hap1 were mainly derived from Huanghuai winter wheat regain.Five candidate genes related to tiller angle were screened by screening the stable genetic loci detected under different treatments.Gene annotation of the genes selected on Ra_c491_902 showed that the genes encoding cytochrome P450 family protein can be used as important genes such as regulating tillering angle,plant drought resistance and defense,to explore the association between genes and phenotype,and lay the foundation for the genetic improvement of tiller-related traits in wheat.

To provide theoretical basis and technical support for rational nitrogen fertilizer management in high-yield cultivation of hybrid wheat,this study aims to investigate the effects of nitrogen application rate on yield formation,dry matter accumulation and distribution,nitrogen absorption and utilization,as well as the nitrogen absorption ratio of wheat fertilizers in two-line hybrid wheat.From 2020 to 2021,three two-line hybrid wheat combinations and one conventional variety were used as materials.A split plot design was adopted,with nitrogen (labeled with ¹⁵N urea) treatment as the main zone and varieties as sub zones.Four nitrogen level experiments were set up at N0,N120,N180,and N240.The dry matter accumulation and distribution,plant nitrogen absorption and utilization,and grain yield of wheat organs were analyzed and measured under different treatments during the flowering and maturity stages.The results demonstrated that a highly significant effect of nitrogen application rate and combination (variety) on wheat yield and yield components.Compared with the conventional varieties Jingdong 17,the average yield of Jingmai 21 and BH9613 increased by 10.47% and 4.07% respectively,mainly due to their higher number of spikes and grains per ear.The application of nitrogen fertilizer significantly increased the number of spikes and grains per ear of wheat,but reduced the thousand grain weight.The application of nitrogen fertilizer to four varieties significantly increased the accumulation of dry matter in wheat during the flowering and maturity stages.The dry matter weight of various organs in wheat during the flowering stage was as follows:stem>leaf>spike,and during the maturity stage,it was as follows:grains>stem>spike-stalk+glume >leaf.The average values of nitrogen fertilizer agronomic utilization efficiency and nitrogen fertilizer partial productivity under different nitrogen application rates were as follows:Jingmai 21>BH9613>Jingdong 17>BH3606,which was consistent with the yield trend.The ¹⁵N atomic percentage of the four combinations (varieties),the nitrogen content from fertilizer,and the proportion of nitrogen from fertilizer all showed the following order:grains>straw,and they significantly increased with the increase of nitrogen application rate.Compared with Jingdong 17,the proportion of soil nitrogen in the three hybrid combinations (varieties) significantly increased,indicating that hybrid wheat had stronger tolerance to barrenness from the perspective of nitrogen utilization.After comprehensive consideration and analysis,the nitrogen application rate of N240 significantly increased wheat yield compared to other treatments,making it the optimal nitrogen fertilizer application rate for wheat cultivation.The comprehensive performance of the two hybrid combinations (varieties) of Jingmai 21 and BH9613 is better than the performance of the control Jingdong 17.

Phytosulfokine receptor(PSKR)plays an important role in promoting plant cell proliferation and is involved in plant response to abiotic stresses.To explore the sequence characteristics and the function of wheat PSKR genes,the cDNA sequences of three homologous genes of TaPSKR1 were cloned from wheat variety Jinmai 47 by homologous cloning technology,named TaPSKR1-6A,TaPSKR1-6B and TaPSKR1-6D because of their locations on chromosome 6A,6B and 6D,respectively.The gene structure,protein physical and chemical properties,cis acting elements,functional domains and evolutionary relationships were analyzed by bioinformatics analysis.The expression patterns of TaPSKR1 genes in different tissues and under different stresses were detected by qRT-PCR.The results showed that TaPSKR1-6A,TaPSKR1-6B and TaPSKR1-6D all contained one exon.The open reading frame(ORF)of the three TaPSKR1 genes were 3 153,3 132,3 156 bp,respectively,which encoded 1 050,1 043 and 1 051 amino acid residues.Bioinformatics analysis showed that TaPSKR1 proteins were located on the cell membrane,containing signal peptide,transmembrane domains,eight LRRs type domains and intracellular kinase domain,which belonged to PSKR gene family.Phylogenetic analysis showed that TaPSKR1 proteins had closely relationship with its related species and rice,which were clustered into the same subgroup.The results of expression analysis showed that TaPSKR1 genes were expressed in roots,stems,leaves and seeds,and the expression levels in roots were the highest.Under drought and salt stress treatments,the expressions of three homologous copies of TaPSKR1 genes were sharply upregulated in leaves,suggesting that TaPSKR1 might play an important regulatory role in wheat defense to abiotic stresses.

In order to clarify the effects of drought stress on the photosynthetic characteristics in flag leaf in the afternoon during grain filling stage and grain yield of winter wheat with different drought resistance,an experiment with two winter wheat cultivars and four water levels was conducted under the condition of rainproof pond cultivation in 2018—2019 and 2019—2020.The two winter wheat cultivars were Jinmai 47(JM47,strong drought resistance)and Yanzhan 4110(YZ4110,weak drought resistance).The four water treatments included severe drought(W1:65% MFC(maximum field water capacity)before sowing + 45%—55% MFC after jointing),moderate drought(W2:75% MFC before sowing + 55%—65% MFC after jointing),mild drought(W3:75% MFC before sowing+65%—75% MFC after jointing),suitable water supply(W4:75%MFC before sowing+75%—85% MFC after jointing).The net photosynthetic rate(Pn),stomatal conductance(Gs),intercellular CO₂ concentration(Ci),transpiration rate(Tr),instantaneous water use efficiency(IWUE),maximum photochemical efficiency of PS Ⅱ (Fv/Fm)and actual photochemical efficiency of PS Ⅱ(ΦPS Ⅱ)in flag leaf from 14:00 to 16:00 during the early,medium and medium-late grain filling stage and the grain yield and its components at maturity were investigated.The results showed that both water and cultivars had significant effects on the photosynthetic and fluorescence characteristics in flag leaf in the afternoon during the grain filling stage and the grain yield at maturity of winter wheat.From the two-year average,compared with W4,the Pn,Gs and ΦPSⅡ in flag leaf in the afternoon during the grain filling stage under drought stress(W1,W2 and W3)respectively decreased by 2.07%—68.92%,-3.23%—50.00% and -1.89%—30.19% in JM47,and decreased by 7.71%—80.19%,11.11%—59.26% and 0—73.47% in YZ4110;the flag leaf Tr values in the afternoon during the medium grain filling stage in JM47 and YZ4110 respectively decreased by 6.30%—32.87% and 6.49%—41.74%,and the flag leaf Fv/Fm values in the afternoon during the medium-late grain filling stage decreased by 1.20%—18.52% and 2.50%—30.00%.In general,for all the above indexes,the decreasing amplitude for the same index was JM47<YZ4110.Compared with YZ4110,the Pn,Gs,ΦPSⅡ and Fv/Fm in flag leaf in the afternoon during the grain filling stage under drought stress(W1,W2 and W3)of JM47 respectively increased by 0.86%—64.89%,8.33%—36.36%,1.96%—184.62% and 1.25%—17.86%,and the grain yields of JM47 were respectively increased by 28.91%,8.06% and 5.40%.Except for IWUE,the flag leaf photosynthetic parameters in the afternoon during the grain filling stage were significantly and extremely significant correlated with grain yield,but the correlation indexes varied with variety and grain filling stage.For JM47,the correlation indexes between the grain yield and flag leaf photosynthetic parameters were highest for Pn,Gs and Fv/Fm during the medium-late grain filling stage,for ΦPSⅡ during the medium grain filling stage,and for Tr during the early grain filling stage.For YZ4110,the correlation indexes were highest for Pn,Gs and Tr during the early grain filling stage,for ΦPSⅡ during the medium grain filling stage and for Fv/Fm during the medium-late grain filling stage.In summary,drought stress decreased the photosynthetic function of flag leaf in the afternoon during grain filling stage and thus decreased the grain yield of winter wheat,the strong drought resistance variety could maintain better flag leaf photosynthetic characteristics in the afternoon during the grain the filling stage under drought stress condition,and significantly improved the ΦPSⅡ of flag leaf in the afternoon during the medium grain filling stage and the Pn,Gs and Fv/Fm of flag leaf in the afternoon during the medium-late grain filling stage,thereby increasing the grain yield.

To study the resistance mechanism of TaHis gene to Fusarium head blight(FHB)in wheat,the full-length coding sequence of TaHis was cloned,and the bait vector pGBKT7-TaHis was constructed,which was then used as bait for screening a yeast two-hybrid library of wheat ear induced by FHB.After obtaining the interacting proteins,yeast two-hybridization and bimolecular fluorescence complementation were further used to verify the interaction between these proteins,and RT-qPCR was used to analyze the expression pattern of TaHis interacting protein induced by FHB in resistant and susceptible cultivars respectively.The results showed that the bait vector pGBKT7-TaHis was successfully constructed,and 18 yeast monoclones were obtained on the four deficient selection medium(SD/-Leu/-Trp/-His/-Ade)after yeast two-hybrid library screening.Blast analysis showed that a total of 5 proteins were obtained,and the coding sequence of serine/arginine-rich mRNA splicing factor SR45a-like(TaSR)was identified in 6 colonies.We cloned the full-length coding region of TaSR gene from Bainong 4299 and constructed pGADT7-TaSR vector.The experiment of yeast two-hybrid showed that the yeast cells co-transformed with pGADT7-TaSR and pGBKT7-TaHis grew well and appeared blue on SD/-Leu/-Trp/-His/-Ade/ X-α-Gal/AbA,indicating that TaSR and TaHis directly interacted in yeast cells.The vectors of YC-TaHis and YN-TaSR were constructed,and the bimolecular fluorescence complementary experiments were performed.The results showed that strong fluorescence signals were generated in tobacco cells co-transferred with YC-TaHis and YN-TaSR,which further verified the interaction between TaSR and TaHis.RT-qPCR analysis of TaSR gene expression showed that TaSR expression was up-regulated in resistant cultivar Bainong 4299,while down-regulated in susceptible cultivar Bainong 607 upon FHB infection,indicating a positive correlation between TaSR expression level and FHB resistance in wheat.To sum up,the interaction between wheat TaSR and TaHis was proved,and TaSR expression level was positively correlated with FHB resistance in wheat.

Breeding resistant varieties is the most economical and feasible method to control wheat leaf rust.In order to further explore the resistance genes,50 wheat varieties were selected in this study,including wheat varieties from Shandong,Henan,Hebei,Shandong and other 8 provinces.Firstly,16 physiological races of leaf rust fungus (THFS,TGTS,THJS,FHKT,FGJN,KHKS,FCJQ,RFKS,THFM,MHGT,KHGS,KBGT,FHGT,PHHT,FHJT,FCJT) were inoculated to 36 vector cultivars containing known leaf rust resistance genes,and 50 wheat varieties tested during the seedling stage.Due to the different virulence of each strain,specific molecular markers closely linked to known disease resistance genes can be combined and analyzed based on the differences in phenotype,and it can be inferred that 50 wheat materials may contain leaf rust resistance genes.The leaf rust resistance genes were identified by genetic deduction,molecular markers and pedigree analysis.The results showed that a total of 9 known resistance genes (Lr1,Lr2c,Lr10,Lr16,Lr26,Lr34,Lr37,Lr45 and Lr46) and a few unknown genes were detected in 50 cultivars.There were 22 varieties including Zimai 12 that contained the Lr1 gene;there were 10 varieties including Lumai 14 that contained the Lr2c gene;Laizhou 9361 only contained the Lr10 gene;there were 25 varieties including Kenong 199 that contained the Lr16 gene;there were 15 varieties including Xuzhou 24 that contained the Lr26 gene;Baomai 3 and Jingdong 8 contained the Lr34 gene;The Lr37 gene was contained in Zimai 12,He 0927,and He 9946;there were 11 varieties including Lianmai 2 that contained the Lr45 gene;there were 38 varieties including Shannong 19 that contained the Lr46 gene.

The effects of sowing date on the yield and yield components of winter wheat,and the response characteristics of growth and development and plant type structure to accumulated temperature were studied in order to clarify the growth characteristics and reasonable plant type structure of wheat adapting to climate change.From autumn 2017 to summer 2019,field trials were conducted in Gaocheng,Hebei Province.Five sowing dates were set,September 25,October 5,October 15,October 25 and November 4.The results showed that the yield of wheat was higher sown from October 5 to 15 than other treatments,and the accumulated temperature before winter was 410-549 ℃.When accumulated temperature before winter was suitable,spike number was high and grain number per spike was moderate.When the accumulated temperature was as high as 733 ℃,the number of invalid tillers was more,the effective tiller rate was lower,and spike number was lower.When the accumulated temperature was insufficient to 279 ℃,the spike number and grain number per spike decreased.Accumulated temperature had a significant effect on growth and development indicators.Under the condition of high and stable yield,the individual index of wheat before winter was put forward:the number of main stem and tillers per plant was 2.3,the number of secondary roots was 2.5,the number of leaves of main stem was 4.1,and the spike differentiation of over winter was single edge stage.The accumulated temperature had an obvious effect on the plant structure of wheat.Delay with sowing date,the flag leaf became longer and wider,the leaf area increased,and the leaf from the top third to the top fifth became narrower and the leaf area decreased.Delay with sowing date,stem diameter of the base increased,the stem length of the top first to top second increased and length of the top third to top fifth decreased,and plant height decreased significantly.According to the equation of yield and accumulated temperature before winter,it was recommended that the suitable sowing time of wheat was October 8 to 14 under high and stable yield conditions,and the accumulated temperature range before winter was 433-541 ℃.Under late sowing conditions,the plant type structure was more reasonable,the growth and development of the plant were moderate before winter,the flag leaf was smaller and its stem length was shorter,and the leaf from the top third to the top fifth from the top was larger and their stem was slightly longer.

Abstract: Tetraploid wheat is the ancestor specie of common wheat and an important food crop.Aiming to provide new resistance sources for wheat variety breeding,the resistance tetraploid wheat germplasm was explored and their resistance genes were identified.TDI-1 is a cultivated emmer wheat that has been immune to powdery mildew in the field for many years.To determine the resistance genes carried by TDI-1,and provide a theoretical basis for genetic improvement of wheat resistance,a durum wheat TDU-1 that was susceptible to powdery mildew was used to hybridize with TDI-1,and their F₁ plants,F₂ population,and F_2:3 lines were obtained.Genetic analysis of resistance was conducted on parents TDI-1,TDU-1,and their hybrid offspring that were inoculated with powdery mildew isolate E09.Then,bulked segregant analysis method combined with molecular markers was used to map the resistance gene.The results showed that TDI-1 was susceptible to E09 during the seedling stage but immune during the adult stage.F₁ plants derived from the cross of TDI-1 and TDU-1 were immune to E09 during the adult stage.The resistance of adult F₂ individuals was separated,and the ratio of resistant and susceptible plants was 3:1($χ_{3:1}^{2}$=0.11,P=0.74);the ratio of the number of homozygous resistant,separated resistant,and homozygous susceptible F_2:3 lines was 1:2:1($χ_{1:2:1}^{2}$=0.47,P=0.79),indicating that the resistance to powdery mildew in the adult stage of TDI-1 was controlled by one dominant gene,temporarily named PmTDI-1.Subsequently,a set of molecular markers was used to amplify the parents and their F₂ population,and then four markers on chromosome 2A,including Xwmc407,NRM-2AS29,NRM-2AS45 and NRM-2AS84, confirmed to be linked to PmTDI-1. PmTDI-1 was between the flanking markers NRM-2AS45 and NRM-2AS84,with genetics distances of 1.8 cM and 4.6 cM,respectively.Therefore,the adult stage powdery mildew resistance gene PmTDI-1 was preliminarily localized on chromosome 2A.This study identified a novel dominant adult-plant-resistance powdery mildew gene PmTDI-1 from tetraploid wheat TDI-1.

The adult plant resistance gene Lr12 exhibits excellent resistance in production systems.To fine map and develop reliable molecular markers for Lr12,a cross was made between the susceptible variety Thatcher and the resistant near-isogenic line RL6011 containing the Lr12 gene.The F₁ generation resulting from this cross was self-pollinated to generate F₂ individual plants and F_2∶3 families.Field evaluations were conducted using a mixture of five highly virulent leaf rust pathotypes (PHTT, THKS, THTT, PHTS, and PHKS) to inoculate F₂ individual plants and F_2∶3 families for adult plant resistance assessment and genetic analysis of resistance.Subsequently,genotyping was performed using a 16K liquid chip on 10 resistant and 10 susceptible individuals from the F₂ generation to identify SNP markers closely linked to Lr12.This enabled the determination of the chromosomal physical interval containing the resistance gene,the development of SSR molecular markers,and the construction of a genetic linkage map.The results indicate that the segregation ratio of resistance to leaf rust in 3 494 F₂ individuals derived from the RL6011(Lr12)/Thatcher cross was consistent with a 3∶1 ratio ( {\mathrm{\chi }}_{3:1}^2=0.14;P=0.71). In the assessment of 685 F_2∶3 families, the segregation ratio among resistant individuals, resistant heterozygous individuals, and susceptible individuals conformed to a 1∶2∶1 ratio ( {\mathrm{\chi }}_{1:2:1}^2=2.01;P=0.37), suggesting that Lr12 is a dominant gene and the population segregation follows Mendelian single-gene inheritance patterns. Genetic linkage map analysis localized the adult plant leaf rust resistance gene Lr12 between SSR molecular markers YK12817 and YK12928,within a genetic interval of 0.38 cM.This corresponds to a physical interval of 2.09 Mb within the physical range of 579.44 Mb to 581.53 Mb on chromosome 4BL of the Chinese Spring reference genome(IWGSC.Ref.V1.0).These findings provide a solid basis for predicting candidate genes.

Wheat stripe rust,caused by Puccinia striiformis f.sp.tritici,is a major disease that severely threatens China's food security.Urediniospores are key agents for the reproduction,dissemination,and infection of the pathogen,but the regulatory mechanisms of sporulation-related genes remain unclear.This study aims to screen and validate the function of the candidate gene PsCON6,which is highly expressed during the early infection stage of P.striiformis,to provide new insights into its pathogenic mechanisms.The PsCON6 gene was obtained from P.striiformis via homologous cloning,and its expression pattern during early infection was analyzed using qRT-PCR.Bioinformatics technology analysis of the amino acid sequence,conserved domains and physicochemical properties of the PsCON6 protein.Barley Stripe mosaic virus host-induced gene silencing(BSMV-HIGS)was used to transiently silence PsCON6,followed by measurements of host reactive oxygen species accumulation,fungal hyphal length and area,and pathogen biomass.Subcellular localization of PsCON6 was determined through transient expression assays.PsCON6 was significantly upregulated during the early infection stage of P.striiformis.The encoded protein contained two conserved conidiation-specific protein 6 domains and consisted of 83 amino acids.After HIGS-mediated silencing of PsCON6,the level of reactive oxygen species in the host significantly increased,while the length and area of the fungal hyphae significantly decreased,whereas urediniospore production remained unaffected.Subcellular localization revealed that PsCON6 was localized to the cell membrane.PsCON6 likely participates in regulating hyphal growth in P.striiformis but does not directly influence urediniospore formation,suggesting potential functional redundancy.The research findings provide new targets for revealing the pathogenic mechanism of wheat stripe rust and lay the foundation for further in-depth analysis of its molecular mechanisms.

In order to study the function and mechanism of the resistance gene of wheat leaf rust,seeds of wheat TcLr19 was treated by EMS.The leaf rust resistance and agronomic traits were investigated and phenotypic mutants were identified in M₁ and M₂.A total of 367 individual plants were obtained in M₁ with different concentrations of EMS.According to the emergence rate,seed rate and mutation rate,EMS 1.0% was considered the optimum concentration.In 2 359 M₂ mutant,a total of 38 phenotype mutations were screened out with 1.61% mutation rate,and a total of 53 susceptible mutations to Puccinia triticina were screened out with 2.25% mutation rate.A total of 146 susceptible plants were obtained in 459 M₃ susceptible populations,especially M₃6-2,M₃33-8,M₃33-9,M₃33-11,M₃44-4 and M₃96-8,and the frequency of susceptible mutation were more than 70%.Furthermore,Lr19 molecular marker-assisted selection was also used in order to guarantee the reliability of the results in the test.The results showed that EMS treatment was an effective method in screening of mutants susceptible to P.triticina.The result not only provided important genetic resources for wheat leaf rust resistance gene cloning and functional genomic research,but also provided new germplasms in wheat breeding.

To identify quantitative trait loci (QTL) for flag leaf length (FLL),width (FLW),area (FLA),thousand grain weight (TGW),grain number per spike (GNS),grain weight per spike(GWS) and understand the genetic relationship among those traits,we developed a doubled haploid(DH)population with 216 lines, derived from the cross between Nongda 3338 and Jingdong 6. The field experiments were carried out in Linfen and Yuncheng in 2015 and 2016, and QTL analysis was conducted by composite interval mapping method combining with genetic maps containing 469 markers. The results showed that a total of 105 additive QTLs were detected,forty of them were QTLs for flag leaf traits and sixty-five were for grain traits,with single QTL explaining 2.28%-39.91% of the phenotypic variances. Several QTLs were identified in the same region or adjacent regions on the 1B,2A,2B,2D,3A,4A,4B,4D,6A,6D and 7A chromosome, these QTLs were closely linked to each other or multi-effect, confirmed those phenotypic data were closely-related under QTL level. Seven QTLs (Qflw-4A.1, Qflw-4B.1, Qflw-4D.1, Qfla-4B, Qtgw-4A.1, Qtgw-4B.2, Qtgw-4B.3) had high LOD value were detected repeatedly under three or four environments. Those seven stable expression QTLs might have great significance for MAS breeding and gene cloning program.

In order to understand the dynamic rules of sugars, starch, protein and trace elements of different types of wheat during grain filling stage under drought stress, and to identify the difference of nutriment between drought and irrigation in the process of grain-filling by high-yield wheat, high-quality wheat and water-saving wheat, the wheat varieties of Jimai 325, Jimai 418 and Jimai 323 in the North of Huang-Huai Region were used as experimental materials. The plants heading and flowering on the same day were selected for marking, and the grains of each variety were taken every 6 days after 7-31 days after anthesis. The effects of drought during grain filling on the contents of total soluble sugar, sucrose, glucose, fructose, protein, Fe, Zn, Mn, Cu, amylose and amylopectin accumulation, starch accumulation rate and the activities of key enzymes in starch synthesis were studied. The results showed that the content of sucrose and glucose in wheat grains was significantly decreased under drought stress, and the effect on fructose content was relatively small, and the sucrose and fructose of high-yielding variety Jimai 325 were less affected by drought in the filling process. Drought stress decreased the content of amylopectin and total starch in wheat grains, but had relatively little effect on the content of amylose. The effect of drought stress on starch content of high-yield and high-quality varieties was significantly greater than that of drought-tolerant variety Jimai 418. The activity of starch synthase was increased in the early and middle stages of filling stage under drought stress, and decreased rapidly in the middle and late stages compared with irrigation control. The content and accumulation of four mineral elements in wheat grains were Mg>Fe>Zn>Mn. With the progress of grain filling, the content of trace elements showed a downward trend. The accumulation of Fe, Zn and Mg in grains of Jimai 325 was higher. The difference of nutrient accumulation in grain filling process of different types of wheat under drought conditions were studied to provide theoretical data and reference basis for optimizing cultivation measures and realizing high quality, high yield and water saving of special wheat.

In order to explore a fast and efficient way to screen drought-resistant varieties of winter wheat, and to select drought-resistant winter wheat varieties. Six winter wheat varieties, Yannong 999, Taimai 1918, Jimai 22, Jimai 23, Taishan 27 and Shiluan 02-1 were used in this study. Normal water treatment(75% relative soil water content), mild drought treatment(55% relative soil water content) and moderate drought treatment(40% relative soil water content) were arranged to explore the chlorophyll fluorescence parameters, biomass, root-shoot ratio, SPAD, superoxide dismutase(SOD) activity, malondialdehyde(MDA) content and their correlations. Results showed that, compared with other varieties, under drought stress, Taimai 1918 obtained the highest drought resistance coefficient(DTC). The smallest reduction of root to shoot ratio, SPAD value, photosystem Ⅱ maximum photosynthetic efficiency(Fv/Fm), photosystem Ⅱ actual photosynthesis efficiency(φPSⅡ), relative electron transfer rate(ETR), SOD, and the largest increasing in non-photochemical quenching(NPQ) and minimal increasing in MDA content were observed in Taimai 1918. The order of drought resistance of 6 winter wheat varieties was Taimai 1918 > Yannong 999 > Jimai 22 > Jimai 23 > Taishan 27 > Shiluan 02-1. The chlorophyll fluorescence parameters were significantly correlated with drought resistance coefficient, SOD activity and MDA content. Sum up, the drought resistance in Taimai 1918 was strongest, and chlorophyll fluorescence parameters can be used for screening drought-resistant winter wheat varieties at seedling stage.

In order to further excavation of the role of wheat stress response genes in plant abiotic stress response,explored the regulation mechanism of abiotic stress response, a MYB gene was screened from a transcriptome result and named Tamyb59, temporarily.The full length sequence of Tamyb59 was cloned by PCR. Sequence comparison and conserved domain were analyzed by NCBI and DNAMAN. Amino acid composition and hydrophilic coefficient were analyzed by online software Expasy and TMHMM. Phylogenic tree was constructed by MEGA 6.0 according to the NJ method. And a fusion expression vector pMDC83-GFP was constructed to identify the subcellular localization. The Real-time PCR (qRT-PCR) was used to analyze the expression characteristics of different tissues in different abiotic stress treatments. The significance was analyzed by SAS. The results showed that:Tamyb59 gene contained a typical conserved SANT domain. The full-length CDS of Tamyb59 was 522 bp,which encoded 173 amino acids with a molecular weight of 19.7 ku and the theoretical isoelectric point was 7.61;Phylogenetic analysis showed that Tamyb59 had 52.0%-85.6% homology with MYB transcription factors of 9 other plants (Aegilops tauschii, Oryza sativa Japonica and Zea may, etc.). Tamyb59 had the highest homology with the MYB sequence of Setaria italica. The protein of Tamyb59 encoded specifically located in the nucleus.qRT-PCR was used to analyze the expression characteristics of different tissues in different abiotic stress treatments. The results revealed that the expression level of Tamyb59 was the highest in the root, and lower in stem, leaf and young spike. Under the PEG and NaCl treatment stress, the expression of Tamyb59 showed a trend of rising first and then decreasing, indicating that Tamyb59 had different responses under different stresses.

In order to explore the effects of nutrient expert (NE) management on nitrogen (N) use efficiency and soil organic carbon (SOC) sequestration in the wheat-maize rotation system and improve its management practices, a long-term experiment was set up in 2009 to compare NE management with farmer's practice (FP) management. Through 9-years experiment, the crop yield, N use efficiency, SOC content, SOC sequestration rate and SOC sequestration efficiency were measured and analyzed. The advantages of long-term NE management in wheat-maize crop rotation system were evaluated. The results showed that long-term NE management reduced the amount of N fertilizer application rate, compared with FP management, but maintained the crop yields (no significant difference with FP). Compared with FP management, the average accumulative recovery efficiency of N, agronomic efficiency of N, and partial productivity of N in NE management system increased by 7.4 percentage points, 39.7%, and 28.4% in maize production system, and increased by 8.0 percentage points, 28.9%, and 32.8% in wheat production system, respectively After 9-years experiment, both NE and FP increased the SOC contents, with NE management increased faster than FP. The annual SOC contents rise rates of NE treatment in 0-5 cm, 5-10 cm and 10-20 cm soil profile were 0.28, 0.27, 0.34 g/(kg·a), respectively, which were 7.7%, 68.8% and 126.7% higher than those of FP treatment. The average annual carbon input of NE and FP treatment from straw returning were 8.5, 8.7 t/(ha·a), respectively, and the SOC sequestration rates were 1.35, 0.68 t/(ha·a),respectively, and the SOC sequestration efficiencies were 18.6% and 0.4%, respectively, which shown a significant difference. NE management could improve N use efficiency and increase SOC sequestration. Long-term NE management is one of the important measures for fertilizer saving, efficiency strengthen and SOC pool richen in wheat-maize rotation system. It would play a crucial role in ensuring food security and realizing agriculture green development.

This study to Laiyang in Chao Soil Region long-term positioning straw of wheat-maize rotation as research object,applying nitrogen fertilizer were studied under the condition of straw returning and the single application organic fertilizer on wheat and maize yield and grain quality of influence.At the same level of nitrogen fertilizer,the two crop straw returning to field application of nitrogen fertilizer (WCN) treatment of wheat,corn grain crude fat content compared with a quarter of straw to field nitrogen fertilizer (WN) treatment significantly increased by 5.72% and 9.49%.The proportion of straw was more conducive to improve the crude fat content of grain.WCN processing wheat,corn grain protein content than those of the other two season straw (WC) treatment significantly improved 32.53%,72.44%,showed that the proportion of nitrogen bigger was beneficial to improving the protein content.Single application of organic fertilizer and two season straw returning to field application of nitrogen fertilizer could significantly improve the yield of wheat and maize.Different straw returning treatment on wheat grain lysine,cystine acid,alanine had little effect,the corn grain cystine acid,glutamic acid,glycine has little effect,except for aspartic acid,leucine,valine,lysine lysine,cystine acid,alanine,long-term different straw also fields of other amino acids.To sum up,the application of nitrogen fertilizer on the basis of straw returning to the field can get higher yield and improve grain quality.

The aims were to study the effect of maize straw returning on soil fertility and productivity under wheat-maize rotation system in North China,and to explore the best way and suitable amount of maize straw returning.From 2021 to 2023,a field split-plot experiment was conducted in Quzhou County,Hebei Province to compare the effects of different maize straw returning methods and amounts on wheat growth,yield composition and soil organic matter content.There were two treatments in the main area,which were cutting and crushing.The sub-area was the amount of straw returning to the field,4 levels,which were 0,0.5,1.0,and 1.5 times of the amount of maize straw in the year.The results showed that compared with straw crushing,the yield of wheat increased by 4.3% under straw cutting treatment,the number of spikes increased by 7.6%,and the harvest index increased by 1.4%,with all significant difference in 2023.The N content of wheat straw was significantly increased by 0.04 percentage points,the N and P uptake of wheat aboveground were significantly increased by 10.8% and 14.3%,respectively(2022),but the K content of wheat straw was significantly reduced by 0.13 percentage points(2023).Cutting treatment could significantly promote the growth of wheat before and after winter,and the NDVI value at jointing stage significantly increased by 11.9%(2022).Soil pH increased by 0.22 units(2023).With the increase of maize straw returning amount,wheat yield and NDVI value at jointing stage showed parabolic model of first increased and then decreased,the N,P and K absorption of above ground wheat showed a significant downward trend,and soil organic matter showed a continuous significant increase trend.Based on the growth potential and yield of wheat,the suitable returning ratio of straw cutting treatment was 58%—62%,and the suitable returning ratio of crushing treatment was 29%—42%.Under the conditions of this experiment,maize straw cutting returning has obvious advantages in promoting wheat growth,and increasing wheat yield.It can be popularized and applied in wheat-maize rotation areas that 58%—62% maize straw is returned into the soil.

The paper studied the effects of carbonization temperature on biochar yield and the physicochemical properties from wheat-straw improved the application of wheat-straw biochar,in order to further expound the mechanism of action of wheat straw biochar.The effects of different carbonization temperatures(100,200,300,400,500,600,700,800℃)on wheat-straw biochar yield and the physicochemical properties (porosity condition,the content of total carbon and inorganic carbon,CEC content,oxygen-containing functional group,pH and FTIR) were studied through mionectic carbonization with the heating rate of 20℃/min. Fourier transform infrared spectrometer was used to obtain infrared spectra and the reasons for the changes of biochar physicochemical properties were analyzed.The wheat-straw of low temperature carbonization was acidic,after 400℃,was alkaline. The degree of wheat straw biochar carbonized increased with the increased of carbonization temperature, and the yield decreased from 91.32% to 18.52% in 100-400℃. In the carbonization process,the wheat-straw biochar porosity increased,the structure was loose. Pore size,specific surface area and specific pore volume showed first increased and then decreased trend,and all reached the maximum at 400℃,were 6.675 m²/g,13.992 nm,0.015 cm³/g respectively.In 200-400℃,the content of organic carbon was high. The content of CEC was maintained at a high level in 400-800℃,between 69.13-84.35 cmol/kg.The analysis of infrared spectrum and surface oxygen functional groups showed that,with the increase of pyrolysis temperature,the degree of aromatization of wheat-straw biochar increased,and the structure became more stable. The carbonization temperature of wheat-straw is more ideal at about 400℃.

Luohan 6 was used as the experimental material in a pot experiment to investigate the effects of zinc fertilizer on root growth and grain yield of winter wheat under drought stress. Four treatments were set up:T1 (normal irrgation+0 mg/kg Zn), T2 (normal irrgation+1 mg/kg Zn), T3 (drought stress+0 mg/kg Zn), and T4 (drought stress+1 mg/kg Zn). The results showed that, compared with T1, the total root length, root mean diameter, total root surface area and total root volume of wheat were noticeably reduced in T3 treatment. The density and diameter of root hair were dramatically decreased, but the difference of root hair length was not significant. The root hair structure was damaged by drought stress, of which the cell wall of root hair became thinner, no nucleus was seen, most of the organelles disintegrated, the inclusion disappeared, and the root hairs decayed. The contents of zinc and indoleacetic acid (IAA) in the root, as well as the root activity, decreased, which resulted in the marked decrease of grain yield per plant. Under T4 treatment, the total root length, root mean diameter, total root surface area and root volume increased observably compared to T3 treatment, and the density and diameter of root hair also increased greatly. The root hair structure was intact, the nucleus was clearly visible, the inclusion was sufficient, and the root hair developed well. In addition, the contents of zinc and IAA in the root, as well as the root activity, likewise ascended remarkably. Compared with T3, the spikes per plant, grain per spike, thousand kernel weight and grain yield per plant of T4 increased by 6.25%, 8.01%, 6.87% and 50.00%, respectively. Comprehensive analysis showed that under the ecological conditions of dryland in Western Henan, the application of zinc fertilizer can enhance the stability of wheat root growth and improve the development of wheat root. As a result, the application of zinc fertilizer has an important role in alleviating wheat yield reduction under drought stress.

This study explored the effects of full-width uniform seeding on the canopy light energy utilization characteristics,dry matter accumulation and transport of winter wheat in saline-alkali land,and clarified the physiological mechanism of high yield and high efficiency,to provide theoretical and practical basis for the promotion of full-width uniform seeding of winter wheat in the Yellow River Delta.In the growing season of winter wheat from 2022 to 2024,Jingyou 368 wheat variety was used as the material,and two seeding patterns of full-width uniform seeding and conventional drill seeding were set up.The differences of yield,dry matter accumulation,dry matter transport,canopy photosynthetically active radiation interception amount and radiation use efficiency under different seeding patterns were analyzed,and the correlation analysis was carried out.The results showed that the yield and spike number of wheat under full width uniform seeding were higher than those under conventional drilling seeding.The full-width uniform seeding achieved extremely significant increases of 18.35% and 46.97% from 2022 to 2023,and 18.71% and 47.21% from 2023 to 2024,respectively.Under the full-width uniform seeding,the wheat stem & tillers number was higher than that under the conventional drilling seeding.From 2022 to 2023,full-width uniform seeding significantly increased the tiller number by 58.83%.From 2023 to 2024,full-width uniform seeding extremely significantly increased the tiller number by 57.30%.The dry matter accumulation of wheat at anthesis stage,dry matter accumulation at maturity stage and dry matter translocation of vegetative organs before anthesis under full-width uniform seeding were higher than those under conventional drilling seeding.From 2022 to 2023,full-width uniform seeding achieved extremely significant increases of 75.78%,41.70% and 109.69%,respectively,and from 2023 to 2024,full-width uniform seeding achieved extremely significant increases of 71.23%,40.81% and 98.07%,respectively.The leaf area index,canopy photosynthetic active radiation interception and radiation use efficiency of wheat under full-width uniform seeding were higher than those of conventional drilling seeding.The full-width uniform seeding in 2022—2023 achieved extremely significant increases of 58.36%,4.11% and 47.17%,respectively,and the full-width uniform seeding in 2023—2024 achieved extremely significant increases of 59.78%,4.11% and 44.00%,respectively.In summary,the full-width uniform seeding of wheat in saline-alkali land improves the canopy light energy utilization performance and tiller productivity by shaping a reasonable population structure and improving the seedbed environment,which is conducive to the formation of plant photosynthetic products and the increase of spike number per unit area,and ultimately achieves high yield of wheat.Therefore,full width uniform seeding is a better seeding pattern for stable and high yield of winter wheat in saline-alkali land of the Yellow River Delta.

In order to further excavate the related genes of wheat vernalization,explored the regulation mechanism of wheat vernalization,this study screened and cloned an EST sequence from a high-throughput RNA sequencing analysis comparing the transcriptomes with wheat varieties with different developmental characteristics under vernalization and non-vernalization treatment,and named Trx59. The open reading frame (ORF) of Trx59 gene was 372 bp,ecoding 124 amino acids,and contained one thioredoxin domain structure. Expression analysis was conducted by qRT-PCR and the gene function was verification by using VIGS technique. The result showed that the expression level of Trx59 was gradually up-regulated during vernalizaton process;the expression level and time of Trx59 gene in spring variety LC10 was higher and earlier than that in winter variety J841. BSMV:Trx59 recombinant vector was built and inoculated wheat plants of J841. After 14 days of inoculation,the leaves appeared visible light bleaching phenomenon,and the expression level of Trx59 reduced sharply,indicating that Trx59 gene had been significantly suppressed;the spike differentiation process of plants inoculated by BSMV:Trx59 was later than that of the negative control group,deducing that the Trx59 genes may be related to the wheat developmental characteristics.

In order to understand the photosynthetic physiological characteristics and dry matter accumulation of different wheat varieties in Huanghuai area at early growth stage, which could provide basis for screening high photosynthetic breeding parents, Wenmai 6, Zhoumai 18, Aikang 58, Bainong 418 and Bainong 419 were used as experimental materials, the photosynthetic rate, chlorophyll content(SPAD), chlorophyll fluorescence parameters, leaf area index(LAI) and dry matter accumulation and change rules of the early growth period were studied.The result showed that Bainong 419 exhibited strong photosynthetic and physiological characteristics.The SPAD of Bainong 419 in January 10, January 25, February 10, March 1, was respectively higher 2.75%, 3.55%, 1.43% and 20.50% than Wenmai 6;higher 8.76%, 10.82%, 15.80% and 16.44% than Zhoumai 18;higher 14.19%, 16.16%, 2.05% and 13.74% than Aikang 58 and higher 14.67%, 10.63%, 6.01% and 13.55% than Bainong 418.In four measurement periods, the maximum photochemical efficiency(Fv/Fm) and electron transfer rate(ETR)of Bainong 419 were all the highest, significantly higher than Wenmai 6 and were also significantly higher than Zhoumai 18 on January 10, January 15 and February 10;photosynthetic rate was higher 20.75%, 14.08%, 2.91% and 13.40% than that of Wenmai 6;higher 44.49%, 31.67%, 14.96% and 20.10% than Zhoumai 18;higher 76.11%, 28.30%, 9.43%, 17.51% than Aikang 58;higher 49.95%, 82.29%, 31.40% and 20.35% than Bainong 418;LAI was significantly higher than other varieties.The physiological properties of Bainong 419 finally induced more dry matter accumulation at early growth stage.Light photosynthetic physiological characteristics results of different wheat varieties at early growth stage showed that Bainong 419 had the potential as high photosynthetic breeding parent.