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.

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.

The identification of the wheat lamina joint regulator LIGULELESS 2 (LG2) and analysis of its interacting proteins are of great significance for exploring the molecular mechanisms underlying lamina joint formation and leaf angle regulation, as well as for breeding new varieties with ideal plant architecture. First, two homologous genes of LG2, designated TaLG2 and TaLG2L, were identified in the wheat genome through phylogenetic analysis, each containing three homoeologous copies located in the A, B, and D subgenomes with more than 90% sequence similarity. Transcriptome-based expression profiling during lamina joint development and in different leaf tissues revealed that both TaLG2 and TaLG2L were specifically expressed in the lamina joint. Except for TaLG2-3A, the other five homoeologs exhibited specific expression at the early S1 stage of lamina joint development. The bait vector pGBKT7-TaLG2L-1A was constructed and used for yeast two-hybrid (Y2H) screening yielding 174 positive clones.Sequencing analysis identified 68 candidate interacting proteins of TaLG2L-1A. GO enrichment analysis showed that these proteins were mainly involved in ubiquitin binding, cation binding, and mRNA binding. Further rotation verification and pairwise Y2H assays demonstrated that TaLG2L-1A can interact with the auxin response factor TaARF17 and the blue light receptor cryptochrome TaCRY1, respectively. This study clarifies the tissue-specific expression patterns of wheat LG2 homologs, identifies and obtains key interacting proteins TaARF17 and TaCRY1 of TaLG2L-1A, and reveals the molecular mechanism by which LG2 may coordinate auxin and light signaling pathways to regulate lamina joint formation and leaf angle development.

The objective of this study was to identify novel major QTLs conferring plant height with breeding potential, and to screen favorable gene loci for marker-assisted selection, so as to provide theoretical basis and molecular resources for plant architecture improvement, lodging resistance improvement and high-yield breeding in wheat. A total of 162 doubled haploid (DH) lines derived from wheat cultivars AN1589 and LX6 were used as experimental materials, which exhibited significant phenotypic variation in plant height. The DH population was genotyped with the wheat 55K SNP array, and polymorphic molecular markers were screened to construct a high-density genetic linkage map. Combined with phenotypic data of plant height collected from six environments across three consecutive years, genome-wide QTL mapping was performed for plant height traits. Four environmentally stable major QTLs were detected via inclusive composite interval mapping (ICIM), which were distributed on chromosomes 4B, 4D, 5D and 6D, individually explaining 7.08%-39.31% of the phenotypic variation. Among them, Qph.ahau-4B was steadily identified in all six environments and BLUP analysis, explaining 28.65%-39.31% of the phenotypic variation. This locus covered a physical interval of 20.61-22.26 Mb, flanked by markers AX-109018264 and AX-109968140, with an additive effect ranging from -9.34 cm to -8.68 cm. This QTL presented prominent genetic effect and high environmental stability, and was verified as a novel and previously unreported major dwarfing QTL by literature comparison. In conclusion, a novel major and environmentally stable QTL for plant height was successfully identified on chromosome 4B. It lays a foundation for subsequent fine mapping, gene cloning and molecular marker-assisted breeding in wheat.

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 suitable cultivation practices for enhancing wheat yield and reducing greenhouse gas CO₂ emissions in hilly drylands of Southwest China,this study employed a two-factor split-plot design.The main plots consisted of straw mulching(SM:8 000 kg/ha)and no straw mulching(NSM:0 kg/ha),while subplots included three nitrogen application levels:no nitrogen(N0:0),optimized reduced nitrogen(N1:120 kg/ha),and conventional nitrogen(N2:180 kg/ha),forming six treatments.The results demonstrated that SM increased wheat yield by 29.4% compared to NSM(2 a).The results of two years showed that the wheat yield of N1 treatment increased by 82.9% and 133.8% respectively compared with N0 treatment,and the wheat yield of N2 treatment increased by 84.6% and 148.9% respectively compared with N0 treatment.Compared with the NSM,the soil water content of SM in the jointing stage,flowering stage and mature stage of wheat increased by 3.31,2.78 and 2.40 percentage points(2 a),respectively.Additionally,compared with NSM,the soil bulk density of SM was significantly reduced.Straw mulching significantly elevated soil organic carbon(SOC)and total nitrogen(TN)contents,while nitrogen application increased TN content.Throughout the entire growth period of wheat,straw mulching increased the CO₂ emission flux,and this flux rose in tandem with the increase in the nitrogen application rate.The cumulative CO₂ emissions of the SM treatment were 45.72% higher than those of the NSM treatment.Similarly,the cumulative CO₂ emissions of the N1 and N2 treatments were 48.88% and 71.70% higher than those of the N0 treatment respectively.A further analysis of the CO₂ emission intensity revealed that straw mulching had no significant impact on the CO₂ emission intensity,whereas the N1 treatment exhibited a significantly lower CO₂ emission intensity than the N0 and N2 treatments.Through Mantel analysis,it was discovered that soil moisture,total nitrogen,organic carbon,and wheat yield had a significant influence on CO₂ emissions.The study demonstrates that the integrated practice of straw mulching combined with 120 kg/ha nitrogen application represents the most suitable cultivation approach for wheat in hilly drylands of Southwest China,achieving optimal balance between economic viability and ecological sustainability.

This study aimed to clone the wheat leaf rust resistance-related gene TaRLKS.2 and detect the kinase activity of its expressed protein,in order to lay a foundation for further exploring the mechanism of TaRLKS.2 in wheat resistance against Puccinia triticina infection and to provide new genetic resources for wheat leaf rust resistance breeding.Using cDNA from the leaf rust-resistant near-isogenic line TcLr26 as a template,the full-length coding region of TaRLKS.2 was cloned.The domain structure of the TaRLKS.2 protein was analyzed using GSDS 2.0 software.A pET28a-TaRLKS.2 prokaryotic expression vector was constructed,and the TaRLKS.2-His fusion protein was induced with IPTG,followed by purification using Ni-NTA affinity chromatography.The kinase activity of the expressed TaRLKS.2 protein was detected using the phosphorylation substrate MBP and Western Blotting.The results showed that the coding region of TaRLKS.2 was 2 244 bp in length,encoding a protein containing two kinase domains with conserved kinase active centers and ATP-binding sites,exhibiting typical characteristics of the RLCK family.Under conditions of 28 ℃ and 0.25 mmol/L IPTG,the TaRLKS.2-His recombinant protein was induced to form soluble protein.After adding the substrate MBP,ATP,phosphate buffer,and protease inhibitors to the purified recombinant protein,the reaction was carried out at 30 ℃ for 30 min.Detection with an anti-phospho-Ser/Thr-Pro antibody confirmed that TaRLKS.2 possesses protein kinase activity.It is speculated that TaRLKS.2 may regulate wheat immune pathways by phosphorylating downstream signaling components,thereby enhancing wheat resistance to leaf rust.

Discovery and mapping of disease-resistant genes in wheat varieties can provide resistance sources,genes and markers for the breeding of new wheat cultivars.KU3067/Apav BC₁F₅ population were used to evaluate for leaf rust resistance at seedling and adult plant stage in Baoding,Hebei Province,and leaf rust resistance gene(s)were mapped using molecular marker technology.At the seedling stage,KU3067 was highly susceptible to three leaf rust physiological races while Apav was highly resistant.The 148 BC₁F₅ lines showed a separation ratio of one pair of genes,indicating that there was a dominant gene in Apav.It was confirmed that the gene was the known leaf rust resistance gene Lr13 using molecular marker technology.Both parents showed high resistance at the adult stage,and the population showed continuous distribution,which was consistent with the characteristics of quantitative traits.Combined with the DArT-Seq data of the population,five leaf rust resistance QTLs were mapped in this population.Lr13,from Apav,was detected in two environments and explained 51.60% and 25.08% of the phenotypic variance,respectively.Lr67 from KU3067 was detected in two environments,explaining 4.98%—7.30% of the phenotypic variance,respectively.QLr.hebau-2AS,from Apav,explained 6.68% of the phenotypic variance.QLr.hebau-5DL.1 from Apav,and QLr.hebau-5DL.2 from KU3067 explained 23.74% and 8.41% of the phenotypic variance,respectively,the two gene might be novel.This study clarified the resistance performance characteristics of the KU3067/Apav population in the Baoding environment,mapped multiple genetic loci including Lr13,Lr67,and three potentially novel leaf rust resistance QTLs,and developed closely linked molecular markers.This provides valuable genetic resources and markers for wheat leaf rust resistance breeding in China.

To elucidate the expression characteristics of the effector protein Pt6647 from Puccinia triticina and further reveal its role in host pathogenicity,the candidate effector protein Pt6647,which was previously identified as highly expressed during host-pathogen interaction,was selected for analysis.We performed gene cloning via PCR,sequence alignment using the NCBI database,signal peptide prediction and functional validation to assess its secretory activity,subcellular localization to determine its cellular distribution,and Quantitative Real-time PCR(qRT-PCR)to examine its expression profile during infection.The open reading frame(ORF)of Pt6647,765 bp in length,was successfully cloned.The gene was highly conserved across eight different physiological races of P.triticina,with only two amino acid variations observed.The Pt6647 protein consisted of 254 amino acids,with its N-terminal 1—18 amino acids confirmed as a functional signal peptide for secretion.Subcellular localization analysis revealed that the full-length Pt6647 protein localized to the cell membrane,while the signal peptide-truncated variant(Pt6647^Δsp)was distributed in the nucleus,cytoplasm,and cell membrane.Expression profiling demonstrated that the transcription of Pt6647 peaked at 36 hours post-inoculation(hpi).The effector Pt6647 was successfully cloned and characterized.Its specific subcellular localization and early infection expression peak suggest that Pt6647 plays a critical role in the initial stages of pathogen invasion.

The aim was to reveal the role of effector protein Pt2567 secreted by Puccinia triticina(Pt) in the pathogenesis and to lay a foundation for clarifying the interaction mechanism between effector protein and wheat.Tobacco transient expression technology,bacterial type Ⅲ secretion system,host induced gene silencing (HIGS) and other technologies were employed to carry out the subcellular localization,inhibition of BAX (mouse Bcl-2 family death promoting protein),effects on callose deposition and reactive oxygen species accumulation and preliminary function analysis of Pt2567.The results showed that the effector protein Pt2567 was subcellular located in the nucleus,and could inhibit BAX-induced programed cell death (PCD).Compared with control group,overexpression of effector protein Pt2567 in TcLr28 significantly enhanced the callose deposition and could increase the active oxygen accumulation at 24 h after the overexpression of the effector protein Pt2567 significantly.The silencing of effector protein Pt2567 on the TcLr28 inoculated with physiological race THTT significantly reduced the disease resistance of TcLr28,and increased the number of uredinium of Pt,and histological observation by confocal laser showed that silencing effector protein Pt2567 accelerated the development of wheat leaf rust.These results all suggest that effector protein Pt2567 plays a positive regulatory role in TcLr28,and is presumed to be a candidate avirulent gene for Lr28.

To identify the suitable sowing date and planting density for the synergistic improvement of yield and quality of strong gluten wheat,the strong gluten wheat variety Kexing 3302 was used as the experimental material.Two sowing dates(October 18(S1)and October 28(S2))and five densities(basic seedlings of 180×10⁴ plants/ha(D180),225×10⁴ plants/ha(D225),270×10⁴ plants/ha(D270),315×10⁴ plants/ha(D315),and 375×10⁴ plants/ha(D375))were set.Field experiments were conducted in 2021—2023 to investigate the effects of sowing date and density on physiological indicators,yield,and quality of wheat plants.The results showed that the relative chlorophyll content(SPAD)of wheat leaves generally decreased with the increase of planting density,and reached its maximum at most growth stages under low-density treatment.With the delay of the sowing date,the relative chlorophyll content of leaves showed an upward trend,with S1 sowing date being lower than S2.As planting density increased,the normalized difference vegetation index(NDVI)generally showed an upward trend,and the NDVI value at S2 sowing date was significantly lower than that at S1 sowing date.The number of spikes and grain yield decreased with the delay of the planting density,but increased with the increase of planting density,with the highest yield under D375 treatment.With the delay of the sowing date,both protein content and wet gluten content generally showed a slight downward trend,but the grain protein content of all treatments was above 13.5%.The total starch content of wheat grains generally decreased with the increase of density at S1 sowing date,but increased with the increase of density at S2 sowing date.In addition,the peak viscosity,trough viscosity,final viscosity,and breakdown value generally increased with the increase of density under the two sowing dates.Parameters such as dough stability time and water absorption rate did not exhibit obvious regular pattern under different sowing dates and planting density,but all met the standards for strong gluten wheat.In summary,at sowing date S1,the planting density of Kexing 3302 at 315×10⁴—375×10⁴ plants/ha can achieve high quality and high yield.

To address the challenges of water scarcity and excessive nitrogen fertilizer application in strong gluten wheat production in the low plain areas of Hebei Province,the effects of water-saving and nitrogen-reduction cultivation modes on grain yield and quality of strong-gluten wheat were studied and evaluated,which provided reference for breeding and cultivation management of strong gluten wheat in this region.Field experiments were conducted in Cangzhou from 2016 to 2018,with the conventional treatment(CK:irrigation of 1 500 m³/ha,nitrogen application of 240 kg/ha)as the control,two experimental groups were established:water-saving(W1:750 m³/ha;W0:0 m³/ha)and nitrogen-reduction(N-:120 kg/ha;N0:0 kg/ha).The yield and quality responses of 13 strong gluten wheat varieties were analyzed.The results showed that in the water-saving experiment,treatments W1 and W0 significantly reduced yield by 20.8% and 38.0%,respectively,compared with CK,while W0 exhibited a significant yield reduction of 21.6% compared with W1.The three tested varieties showed strong drought resistance and water-saving characteristics.Treatment W1 significantly prolonged the dough stability time by 8.25 min, while treatment W0 led to a significant decrease in protein content by 1.0 percentage point and a notable reduction in flour water absorption by 2.25 percentage points.Under reduced nitrogen treatment (N-), yield decreased by 3.7% compared to CK, but nitrogen absorption and utilization efficiency increased significantly by 9.8 percentage points.The treatment N0 showed a significant yield reduction of 15.8% and 12.6% compared to CK and N-, respectively. For dough quality, treatment N- increased the stability time by 0.6 min and the extensibility area by 0.35 cm², while treatment N0 caused a significant decrease in protein content by 0.8 percentage points and a reduction in other quality indicators.Principal component analysis showed that the treatment W1 achieved the highest comprehensive quality score(W1>CK>W0),among nitrogen reduction treatments,the ranking was CK>N->N0.Cultivars Shiluan 02-1,Gaoyou 5218,Gaoyou 5766,and Gaoyou 2018 demonstrated stable quality performance across all treatments,and can be used as excellent breeding materials.The conclusions showed that in the low plain areas of Hebei,moderate water stress(W1)could improve certain quality traits despite causing yield reduction;halving nitrogen application(N-)maintained stable yield while significantly improving nitrogen fertilizer absorption and utilization efficiency without affecting quality.The responses of strong gluten wheat to water and nitrogen regulation were asynchronous between yield and quality,and among different quality characteristics.Therefore,both breeding programs and cultivation management should adopt multi-objective synergistic optimization strategies to achieve balanced improvement in both yield and quality.

In order to elucidate the molecular mechanism of flour-quality regulation at the transcriptional level,wheat mutant varieties A94 and A261 were obtained by ⁶⁰Co-γ irradiation mutagenesis of Shimai 15,and the developing seeds at days 7,14,21 and 28 after flowering were subjected to transcriptome sequencing,and water absorption,dough development time,stable time,softening degree and farinogram index of the three varieties were measured.The results showed that farinogram parameters of two mutant varieties were better than those of Shimai 15.Twenty-four samples were sequenced,and after the data were filtered and annotated,a total of 26 714 genes were identified.With respect to Shimai 15,there were 1 042,258,301 and 366 differentially expressed genes(DEGs)at four time points in A94,respectively,and there were 2 178,248,117 and 959 DEGs in A261,respectively.KEGG enrichment showed that DEGs were mainly involved in pathways of starch and sucrose metabolism,protein processing in endoplasmic reticulum.GO enrichment showed that DEGs were mainly involved in glycogen biosynthesis processes,amyloplast and other biological processes.By analyzing the differential genes in these pathways and biological processes,it was hypothesized that the reasons for the improved flour quality in the mutant varieties include the up-regulation of genes related to sucrose and starch synthesis and metabolism in the early stages of filling,the degradation of misfolded proteins in the middle and late stages,and the differential expression of genes regulating protein and starch accumulation.

Wheat leaf rust and wheat powdery mildew are two important diseases in the world.Cultivating and planting disease resistant varieties is the most economical and effective method to control these two diseases.In order to test the distribution of wheat leaf rust resistance gene Lr21,the molecular marker closely linked to Lr21 was used to detect 1 200 wheat varieties(lines),and 23 wheat varieties(lines)were detected to contain Lr21.The molecular markers related to other leaf rust resistance genes were used to detect 23 wheat materials,Lr20 gene was detected in Gaoyou 2018,Lr37 gene was detected in Aifeng 8,Jingdong 22,Zhongmai 175,Luyuan 205 and Tang Y958,and Lr46 gene was detected in Jinan 17.No wheat varietie(line)was detected to contain Lr9,Lr10,Lr19,Lr24 or Lr34.Resistance evaluation of 23 wheat varieties(lines)containing Lr21 was identified using the epidemic races of Puccinia triticina(Pt)and Blumeria graminis f.sp.tritici(Bgt),respectively.The results showed that seven wheat varieties(lines)were resistant to both Pt and Bgt,with a frequency of 30.43%,and six wheat varieties(lines)were susceptible to Pt and Bgt mildew at the same time,and the frequency was 26.09%.Taken together,Lr21 was detected in 1 200 wheat cultivars(lines),as well as the presence of other rust resistance genes,and further evaluated their resistance to Pt and Bgt,which will provide a theoretical basis for the selection of multi-resistant wheat.

Wheat,as one of the world's major food crops,its growth and development,yield,and quality are often constrained by abiotic stresses. To cope with these abiotic stresses,wheat has evolved a series of response mechanisms,including signal perception,signal transduction,and gene expression regulation,to maintain cellular homeostasis and protect the functions of biological macromolecules. Drought stress causes the accumulation of osmotic-adjustment substances and antioxidants in wheat,a decline in the photosynthetic rate,and alterations in morphological structure. Its molecular mechanisms mainly involve pathways such as reactive oxygen species (ROS) signaling,hormone signaling,and gene expression regulation. Saline-alkali stress inhibits seed germination and seedling growth,leading to photosynthetic impairments,osmotic-regulation imbalances,ion-balance disorders,and membrane-lipid oxidation. Under such circumstances,wheat can enhance salt tolerance by activating the salt overly sensitive (SOS) signaling pathway,calcium-ion signaling,hormone signaling,and gene-expression regulation. Extreme temperature stress inhibits photosynthesis,triggers membrane-lipid oxidation,and promotes the accumulation of osmotic-adjustment substances. Its regulatory mechanisms mainly involve hormone signaling,transcriptional activation,and epigenetic regulation. This study reviews the response mechanisms of wheat to drought,saline-alkali,and extreme temperature stresses and looks ahead to future research directions:focusing on the cross-interaction mechanisms of multiple stresses and mining genes responsive to combined stresses; effectively integrating stress-resistant traits into high-yield and high-quality genetic backgrounds to achieve the coordinated improvement of ideal plant types and stress resistance; promoting the in-depth integration of modern biotechnology with conventional breeding methods to enhance breeding efficiency. It aims to provide comprehensive theoretical support and technical references for the genetic improvement of wheat's resistance to abiotic stresses.

It is important for agricultural production to study the spatial and temporal distribution of winter wheat drought in Hebei Province.Based on the meteorological observation data of 119 national meteorological stations in Hebei Province during the growing period of winter wheat from 1991 to 2021,based on the national standard of"Meteorological Drought Grade"(GB/T 20481-2017),we calculated the meteorological drought composite index(MCI)and analyzed the spatial and temporal distribution characteristics of winter wheat drought in Hebei Province in recent 30 years.The results showed that:the frequency of drought decreased gradually with the drought grade from light drought to extreme drought.The average frequency of light drought occurrence in different growth stages of winter wheat in Hebei Province ranges from 22.1% to 22.5%.The average frequency of medium drought occurrence ranges from 11.7% to 14.5%.The average frequency of heavy drought occurrence ranges from 3.6% to 5.5%.The average frequency of extreme drought occurrence ranges from 0.4% to 1.0%.During the whole growth period,the areas with relatively high frequency of occurrence of medium drought and above were mainly distributed in most parts of Hengshui,west and south of Cangzhou,east of Xingtai,and east of Handan,and the frequency of occurrence was more than 20.25%.From 1991 to 2021,the drought intensity and range of winter wheat in Hebei Province showed a significant decreasing trend in the middle and later stages of growth.

It aims to evaluate the storage tolerance of 20 popular wheat varieties from the Huang-Huai wheat region under natural aging conditions and classify them,thereby providing a theoretical basis for the breeding and selection of storage-tolerant wheat varieties.The experiment involved natural aging treatments of 12 and 24 months,with seeds harvested 3 months prior serving as the control.Measurements included seed vigor,seed coat characteristics(color and cell membrane integrity),and physiological and biochemical indicators(soluble sugar,gluten protein,starch content,antioxidant enzyme activity,and malondialdehyde content).The results indicated that as aging time increased,seed vigor of all varieties significantly declined.Germination rate and germination potential decreased by 2.17-10.79 percentage points and 2.80-23.39 percentage points,respectively,after 12 months,and further declined by 15.95-25.88 percentage points and 14.93-41.44 percentage points after 24 months.The hue,saturation,and intensity of seed coat color decreased,while electrical conductivity increased,indicating gradual damage to the seed coat cell membrane.Among the physiological and biochemical indicators,except for malondialdehyde,soluble sugar,protein,starch content,and antioxidant enzyme activity all showed a declining trend,with greater declines observed after 24 months compared to 12 months.Total starch content exhibited the most significant decrease,declining by 6.43-32.13 percentage points and 21.02-44.95 percentage points after 12 and 24 months,respectively.Based on indicators such as germination rate,seed coat color,electrical conductivity,soluble sugar,and antioxidant enzyme activity,the 20 wheat varieties were classified into storage-tolerant,moderately storage-tolerant,and non-storage-tolerant types.Among them,Annong 0711,Luohan 19,and Xinmai 26 demonstrated strong storage tolerance.The findings provide parental materials,evaluation criteria,and theoretical references for the breeding of storage-tolerant wheat varieties.

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.

In order to explore the effects of silicon fertilizer on lodging resistance,growth and development,yield,and quality of winter wheat,Kenmai 58 was used as the experimental material.The treatments included 15 kg/ha (Si1) and 30 kg/ha(Si2)silicon fertilizer applied as basal fertilizer,15 kg/ha (Si3) and 30 kg/ha(Si4) silicon fertilizer applied as topdressing at jointing stage,and no silicon fertilizer (CK).The stem lodging resistance at grain filling stage,plant growth,yield,and quality were measured.The results showed that Si4 significantly reduced the plant height,height of gravity center,and the length of the basal second internode.Compared with CK,Si3 increased the thickness of the basal second and third internodes by over 14.7%.Si2 and Si4 increased the plumpness and breaking resistance of the basal second or third internodes by 8.6%—18.7% and by 12.4%—49.2%,respectively.Nevertheless,silicon fertilizer had no effect on the diameter and dry weight of the basal internode.Moreover,silicon fertilizer increased the chlorophyll content (SPAD) of leaves at jointing stage,but had no effect on tillering,productive tiller percentage,dry matter accumulation,harvest index,yield,and main quality indexes.In summary,the application of silicon fertilizer improved the stem lodging resistance by lowering plant height,gravity center height,and basal internode length,while increasing the basal internode thickness,plumpness,and breaking resistance.Silicon fertilizer also increased chlorophyll content (SPAD) without adversely affecting wheat growth,grain yield,or quality.Silicon fertilizer could be applied either as basal fertilizer or topdressing at jointing stage.

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.

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.

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.

To investigate the effects of delayed sowing on the growth,development,grain yield and quality of wheat,Yunong 907(YN907)and Yunong 922(YN922),two new high yield and high quality wheat varieties,were selected as experimental materials.Three sowing dates were established:October 22nd(S1,the conventional sowing date),October 31st(S2,delayed sowing by 9 days),and November 9th(S3,delayed sowing by 18 days).The study investigated the effects of delayed sowing on the phenological stages,grain yield and flour quality of wheat,and analyzed the relationship between temperature characteristics and wheat yield,and quality under delayed sowing conditions.The results indicated that compared with the conventional sowing date, the full growth period of YN907 and YN922 was shortened with the delay of sowing date in both years. The accumulated temperature before winter and the average daily temperature before heading decreased with the delay of sowing date, while the average daily temperature and effective accumulated temperature after heading increased. The effective accumulated temperature of the full growth period showed a downward trend. The effective accumulated temperature of the full growth period of YN907 and YN922 in S3 treatment was 243.95,222.10 ℃·d lower than that in S1 treatment in 2022—2023, and 136.30,189.40 ℃·d lower in 2023—2024, respectively. The yield and its components decreased with the delay of sowing, with a yield reduction of 6.45% to 17.26%. Compared with the conventional sowing date, the wet gluten content and protein content increased under the delayed sowing conditions.Under the background of climate warming and the scale-up of the agricultural operation,the sowing date of wheat can be adjusted to adapt to the temperature change.YN907 and YN922 had the highest yield on October 22nd.Delaying the sowing date to October 31st could maintain the higher yield level and increase the grain protein content.When the sowing date continues to be postponed,the grain protein content will be significantly increased but the yield will be significantly decreased.

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.

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.

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.

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 explore the potential biological functions of HBD family members in the important cereal crop wheat,it first conducted a bioinformatic analysis of the HBD family members and their sequence characteristics in common hexaploid wheat.Subsequently,transcriptome and Real-time Quantitative PCR(qRT-PCR)analyses were performed to assess their expression patterns and functions.The results identified a total of 90 wheat HBD genes,which contained between 2 and 18 exons and comprised 111 to 1 863 amino acids;they could be divided into six subgroups based on their evolutionary relationships.The tissue expression pattern results showed that most HBD genes were relatively highly expressed in the roots,stems,spikes,and grains of the plants,while their expression in leaves was relatively low,reflecting the diversity of their biological functions.The promoter regions of these HBD members contain 62 types of cis-acting elements,mainly involved in light and hormone regulatory elements that participated in stress responses.Different members of the HBD gene family responded to various abiotic stresses,including phosphorus,salinity,low temperature,high temperature,drought,and heat-drought synergistic stress.Among these,TaHBD23,TaHBD28,TaHBD67,TaHBD78,and TaHBD85 showed significant differential expression under various stresses,serving as important candidate genes for stress response.In response to biotic stress,the number of HBD family genes responding to Fusarium pseudograminearum and Pseudomonas translucens was fewer than those responding to F.graminearum, suggesting their critical role in the response to F. graminearum resistance.Further research on the transcriptome data from wheat Bobwhite materials infected with F.graminearum and treated with water identified 41 HBD genes with significantly changed expression levels.Among them,10 genes overlapped with the database,and quantitative analysis was consistent with the trends in transcriptome data,indicating that TaHBD28/17,TaHBD67,and TaHBD90/84 negatively responded to Fusarium head blight,while TaHBD39/37,TaHBD45,and TaHBD68/79 positively responded to Fusarium head blight.

Cloning the wheat grain superoxide dismutase(SOD)gene and developing competitive allele-specific PCR(KASP)markers related to SOD activity are of great significance for breeding wheat varieties with high SOD activity.According to the gene ID,specific primers were designed to clone the gDNA sequence of TaSOD-B1 gene.The single nucleotide polymorphism(SNP)loci were obtained by comparing the wheat genome genetic variation and Ensembl Plants database,and the KASP markers closely related to the SOD activity of wheat were developed.The practicability of the markers was verified by the correlation analysis between SOD activity and genotypes of 287 winter wheat varieties(lines).The TaSOD-B1 gene fragment of Chinese spring variety was amplified by six pairs of specific primers,and the TaSOD-B1 gene on chromosome 5B was obtained by splicing.The full length of the gene was 6 491 bp,including an open reading frame(ORF)of 1 650 bp,which encoded a total of 549 amino acids.The predicted molecular weight was 60.80 ku,the gene was composed of 12 exons and 11 introns.The intron conformed to the typical GT-AG structure.The KASP marker was developed based on the 44th base of the first exon of the TaSOD-B1 gene,and was verified by sequencing.The results showed that the genotype of the allelic variation type TaSOD-B1a was AA,which was associated with high SOD activity,and was labeled with the fluorescent gene FAM(shown as blue).The genotype of TaSOD-B1b was GG,which was associated with low SOD activity and was marked with the fluorescent gene HEX(shown as red).The detection of 287 winter wheat varieties(lines)at home and abroad showed that the SOD activity of different genotypes was significantly different.Based on the TaSOD-B1 sequence,a set of KASP markers related to SOD activity was successfully developed and could be used for genetic improvement of SOD activity.

In order to investigate the effects of different mulching measures on soil moisture and heat status and yield of winter wheat in northwest dry area,winter wheat Kangzhuang 974 was used as test material.From September 2022 to July 2023,three different coverage treatments including wheat straw strip covering three rows(M3),four rows(M4)and five rows(M5)and plastic film covering(PM)treatment were set up in the experimental base of Gansu Agricultural University,The open field(CK)was used as the control.The results showed that:compared with CK,the soil water storage of 0—200 cm during the whole growth period of winter wheat was significantly increased by mulch,the average increase of straw strip mulch was 13.22%,the increase range was M3>M4>M5,and the PM increased by 19.65%.The soil moisture increasing effect of mulch increased gradually with the progress of growth stage,and the maximum increase was 37.53—87.76 mm at maturity stage.It decreased with the deepening of soil layer,and the increase of 0—20 cm was the largest,ranging from 5.10—9.48 mm.Mulching significantly reduced the total water consumption and total water consumption intensity during the whole growth period,and the influence of mulching on water consumption and total water consumption intensity during the later growth period was most obvious.Compared with CK,wheat straw strip mulching significantly reduced the soil temperature of 0—25 cm during the whole growth period by 1.60—2.70 ℃,and M3 treatment had the largest decrease.The maximum decrease occurred at the grouting stage(3.67 ℃),and the maximum decrease between soil layers(3.01 ℃)occurred at 5 cm.Compared with CK,PM significantly increased the soil temperature from 0 to 25 cm during the whole growth period by 1.50 ℃,and the overwintering period and 5 cm had the largest increase,which were 2.20,1.79 ℃,respectively.The temperature of straw mulch increased at 7:00 at wintering stage,jointing stage and ripening stage,and the temperature increased and decreased at other times.PM temperature increased at all time except at 14:00 in grouting stage and ripening stage.Compared with CK, the yield and water use efficiency of M5 and PM were increased by 8.67%, 26.49% and 0.96, 2.94 kg/(ha·mm), panicle number was the most significant factor(CV=17.67%).Yield was significantly positively correlated with spike number(r=0.754^**),WUE(r=0.891^**)and soil temperature(r=0.723^**),and significantly positively correlated with grain number per spike(r=0.522^*).Banded mulching of wheat stalk can achieve both ecological and economic benefits,and M5 is more conducive to the formation of yield.

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.

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 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.

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.

To investigate the impact of saline water irrigation on greenhouse gas emissions,including CO₂,N₂O,CH₄,and the soil microbial community in winter wheat fields,three types of saline water with different salinity levels(1,3,and 5 g/L,denoted as W1,W3,and W5)were employed.Field experiments were conducted at the Nanpi Eco-Agriculture Experimental Station of the Chinese Academy of Sciences from March to June 2023.The results indicated that CO₂ emissions had similar trends in the different saline water irrigation treatments during the wheat growing stages,which were high in the early stage,low in the middle stage,and high in the late stage.N₂O emissions exhibited a trend of high values in the early period and lower values in the later stages.While,CH₄ showed fluctuations between positive and negative emissions.Comparative analysis revealed that the average CO₂ and N₂O emission rates in W3 treatment were significantly lower than in W1,with reductions of 39.4% and 68.9%,respectively.The average CO₂ and N₂O emission rates in W5 treatment decreased by 21.9% and 40.0%,although the difference was not statistically significant.Saline water irrigation with different concentrations minimally affected soil microbial α-diversity but significantly altered community structure.Cluster analysis demonstrated a significant difference in microbial composition between W1 and W5,with W3 positioned between the two treatments.Correlation analysis showed that there was a significant positive correlation between CO₂ and N₂O emission rates and soil TN,while there was a significant positive correlation between N₂O emission rate and soil TN,TOC,DOC,MBC,respectively.Soil N₂O and CH₄ emission rates correlated positively with the abundance of S0134 terrestrial and Sphingomonas and Subgroup 25,respectively.Redundancy analysis(RDA)identified pH,NH₄⁺,EC,and DOC as key physicochemical factors influencing the abundance of Sphingomonas and Subgroup 25.In conclusion,irrigation with 3 g/L mildly saline water can reduce soil respiration rates and decrease agricultural carbon emissions without significantly increasing soil salinity,providing theoretical support for the development and utilization of mildly saline water resources in the North China Plain.

Vernalization is a unique and necessary physiological stage in the growth and development of winter wheat,which determines the ecological adaptability and yield of winter wheat.This paper briefly summarizes the production and application value of vernalization of winter wheat.By summarizing and analyzing the structure and function of the key genes TaVRN1,TaVRN2 and TaVRN3 in wheat vernalization and their regulatory networks,it is believed that the study of epigenetic regulation of TaVRN1 is the core work of wheat vernalization mechanism analysis.Combined with the existing research on the expression regulation of TaVRN1,the causes of the difference in vernalization demand of wheat,the mechanism of long-term low temperature perception in winter,the research progress of overwintering memory and overwintering memory reset after vernalization,and the effect of vernalization on the regulation of cold tolerance,spikelet development,tillering and other agronomic traits of wheat were mainly introduced.In addition,this study summarizes the unsolved scientific problems in vernalization,and discusses the future research direction of wheat vernalization,which provides reference suggestions for the research of high yield and rapid breeding of wheat.

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.

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 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.

To clarify the effects of sulfur application at different stages on the yield and photosynthetic characteristics of strong-gluten wheat,and to determine the appropriate time for sulfur fertilizer application,from 2019 to 2021 during two wheat growth seasons,using strong-gluten wheat Gaoyou 2018 as the experimental material,three sulfur application periods were set:before sowing (S60-b),topdressing at jointing stage (S60-j),and topdressing at anthesis stage (S60-a),with a sulfur application rate of 60 kg/ha,and no sulfur application (CK) as the control.The effects of leaf area index (LAI),relative chlorophyll content of flag leaf (SPAD),soluble protein content,soluble sugar content,yield and components of strong-gluten wheat under different sulfur application treatments were studied systematically.The results showed that compared to CK,S60-b,S60-j and S60-a could all significantly increase the thousand-grain weight (TGW),maximum grain filling rate and yield of Gaoyou 2018.In the two growing seasons,the average increase of TGW was 6.23%,4.27% and 7.04%,respectively;the increase of TGW was the highest at 35 days post anthesis,which was 5.51%,3.17%and 6.12%,respectively.The average increase of maximum grain filling rate was 2.84%,1.76% and 3.49% and the average increase in yield was 9.20%,2.73% and 5.71%,respectively.However,sulfur application had no significant effect on the number of ears and grains per unit area of Gaoyou 2018.Sulfur application at different stages had significant effects on the photosynthetic characteristics of strong-gluten wheat.The LAI,SPAD value of flag leaves in the middle and late stages of growth,the soluble protein content of flag leaves at 22 and 29 days post anthesis and soluble sugar content in flag leaves at 35 days post anthesis were significantly increased by S60-b and S60-a treatments.The five above indexes increased by more than 26.16%,7.38%,16.90%,55.29% and 81.11%,respectively.According to the results of two years,before sowing and topdressing at the anthesis stage with sulfur fertilizer could significantly increase the LAI of flag leaves in the middle and late growth stage,maintain high SPAD value,delay flag leaf senescence,increase the contents of soluble protein and soluble sugar,TGW and filling rate at the end of grain filling,showing higher yield.In summary,sulfur application have a positive regulatory effect on the yield of strong-gluten wheat,and before sowing and topdressing at the anthesis stage have a good regulatory effect.

In order to investigate the effects of density on individual and population structure characteristics and yield of winter wheat under rainfed and limited water supply conditions,a field experiment was carried out at Gaocheng Experimental Station,Shijiazhuang City during 2022-2023 season using JM22 wheat cultivar under four densities:which were 1.8×10⁶ (D180),3.0×10⁶ (D300),4.2×10⁶ (D420) and 5.4×10⁶ (D540) plants/ha.Two irrigation treatments for each density,which were no irrigation during the whole growth period (W0) and irrigated once at the jointing stage (W1).The influence of planting density and irrigation treatments on leaf area (flag leaf,top 2 nd leaf,top 3 nd leaf,top 4 th leaf),non-leaf green organs (ear,awns,stem sheath) area,leaf area index,non-leaf green organ area index,dry matter accumulation,photosynthetic active radiation interception rate,water use efficiency (WUE) and yield of winter wheat were studied.The results showed that the leaf area of each leaf layer and non-leaf green organs decreased with the increase of density.D300 treatment got the highest leaf area index and non-leaf green organs index,and significantly higher than that in D540.The contribution of post-anthesis dry matter to grain yield was more than 70%.Compared with D540 treatment,reducing plant density decreased the transfer of dry matter before anthesis,but increased the accumulation of dry matter after anthesis and its contribution to grain yield.With the increase of density,WUE increased first and then decreased,D300 treatment achieved the highest WUE.Specifically,the WUE of D300 was 1.2%-14.4% and 2.5%-12.7% higher than that of other densities under W0 and W1,respectively.Compared with W0,W1 treatment increased the area of leaf and non-leaf green organs of different densities,delayed leaf senescence,and improved the photosynthetic active radiation interception rate of canopy.Ultimately,the grain yield increased by 28.1%-39.7%.Under the conditions of this experiment,D300 treatment increased the leaf and non-leaf green organ area,leaf and non-leaf green organ area index,canopy photosynthetically active radiation interception rate,post-anthesis dry matter accumulation and its contribution to final grain yield.The yield of D300 was 2.4%-6.6% and 0.3%-9.7% higher than that of the other densities under W0 and W1,respectively,which was the optimal density in this study.

In order to clarify the effect of fertilizer reduction on wheat yield and starch particle size distribution characteristics, seven fertilization treatments were set up with wheat varieties Longke 1109 and Yangmai 25 as materials.No nitrogen fertilizer (CK),farmer's customary nitrogen application rate (ternary compound fertilizer 750 kg/ha+ topdressing 150 kg/ha urea,CF),slow-release fertilizer 900 kg/ha one-time base application (SF900),slow-release fertilizer 750 kg/ha one-time base application (SF750),slow-release fertilizer 600 kg/ha one-time base application(SF600),slow-release fertilizer 750 kg/ha base application+topdressing 150 kg/ha urea (S750T),slow-release fertilizer 600 kg/ha base application + topdressing 150 kg/ha urea (S600T).The effects of slow-release fertilizers on grain yield and starch particle size distribution of wheat were analyzed.The results showed that under the condition of reducing fertilizer application,the spike number first increased and then decreased,the grain number per spike decreased,the 1000-grain weight increased,and the yield of wheat under SF750 treatment was the highest.The content of wet gluten and protein decreased and the content of starch increased in two stubble.The volume and proportion of surface area of B-type starch in strong and weak grains first increased and then decreased,while the proportion of the volume and surface area of A-type starch grains decreased first and then increased in dry stubble.In rice stubble,While the proportion of the volume and surface area of B-type starch grains increased,while those of A-type starch grains decreased.The gelatinization parameters of the two stubble decreased.In summary,the reduction of fertilizer application mainly affects the grain size distribution of endosperm starch,decreases indicators such as gelatinization parameters,and increases grain yield and starch content,which further decreases the content of wet gluten and protein.Compared with the customary nitrogen application rate of farmers,reducing fertilizer application increases wheat grain yield,increases wet gluten and protein content,and decreases starch content.

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.

In order to further explore the function of TaMAPK5 in the interaction between wheat and Puccinia triticina,the CDS region of TaMAPK5 gene was cloned,and the prokaryotic expression vector pET28a-TaMAPK5 was constructed and transformed into E.coli BL21(DE3).The optimal concentration,induction time and induction temperature of isopropyl β-D-thiogalactoside (IPTG) induced expression of the target protein were explored,and the target protein was purified by Ni-NTA affinity chromatography.The purified recombinant protein was used to immunize New Zealand rabbits to prepare TaMAPK5 polyclonal antibody.The results showed that the full length of the CDS region of TaMAPK5 was 1 110 bp,and the TaMAPK5 recombinant protein was induced with IPTG at a final concentration of 0.050 mmol/L and incubated at 16 ℃ for 48 h.The recombinant protein was used as an antigen to immunize New Zealand rabbits,and a polyclonal antibody capable of specifically recognizing TaMAPK5 was successfully prepared.The antibody titer was 1∶51 200.The results of Western Blot showed that TaMAPK5 was induced by P.triticina infection in wheat and P.triticina incompatible combinations.The recombinant protein TaMAPK5 was successfully expressed and purified,and its polyclonal antibody was prepared.It was revealed that TaMAPK5 protein may positively regulate wheat resistance to leaf rust infection.

Clarifying the effect of spring limited irrigation on the root development and grain yield of winter wheat in Haihe Plain is of great significance to reduce irrigation and improve water use efficiency.This study used Shimai 22 as the test material,irrigation treatments were traditional irrigation twice at jointing and anthesis stage(W2),no irrigation(W0),and single irrigation(W1)with four irrigation-time treatments(3L,4L,5L,and 6L)based on the number of leaves unfolded in spring.The results showed that compared with W2,W0 and W1 yield decreased by 54.6% and 24.4% respectively,the irrigation yield was highest at 4L in W1,and the effect of yield composition reduction was not significant.Limited irrigation reduced the total root weight density and root length density of winter wheat.During the anthesis period, the total root weight density of W1 decreased significantly by 17.2%, while the total root weight density and root length density of W0 decreased significantly by 47.5% and 35.1%, respectively. And under W1 condition, 4L has the highest total root weight density and root length density. The vertical distribution of roots showed that reducing the frequency of irrigation increased the distribution of roots in the soil layer below 40 cm,however,with the postponement of irrigation time,the root distribution of W1 deep soil decreased and root vigor increased.Among them, during the anthesis period, 4L was significantly higher than 6L by 28.8%, 14.2%, and 36.5% in the 120—160 cm, 160—200 cm, and 200—240 cm soil layers, respectively. Correlation and path analysis showed that total root weight density and root length density at joint—anthesis period had a positive effect on yield.The direct contribution of total root length density in 3L and 4L irrigation was the largest.Generally speaking,the root mass of 4L treatment was higher at jointing-anthesis period,the deep root distribution and root activity of 40—240 cm were increased,resulting in higher spike number and kernel number,which was beneficial to alleviate the decrease of winter wheat yield at limited irrigation,it can be used as an effective way of limited irrigation for winter wheat in Haihe Plain.

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.

Calcium and potassium are important mineral nutrient elements in wheat.It is significant to explore the related genetic mechanisms and effects on human nutritional health.To provide a theoretical basis for biofortification breeding of trace elements in wheat grains,we used 164 F₆ recombinant inbred lines(RILs)derived from Avocet/Chilero(AC)and 175 F₆ RILs derived from Avocet/Huites(AH).Our investigation focused on phenotypic variations in grain calcium(GCa)and grain potassium(GK)content in five environments.QTL mapping was conducted with diversity arrays technology(DArT)chip.Nineteen QTLs associated with grain calcium content were identified,distributed on chromosomes 1A,1D,2A,2B,3A,3D,4A,4B,4D,5A,5B,7A,7B,and 7D,explaining 3.23%—16.29% of phenotypic variation.Simultaneously,23 QTLs linked to grain potassium content were identified on chromosomes 1B,2A,2B,3A,3B,4A,4D,5A,6A,6B,and 7D,explaining 3.31%—24.66% of phenotypic variation.QGCa.haust-1A,QGCa.haust-AC-5A and QGK.haust-AC-2A.2 were located in multiple environments.QGCa.haust-1A and QGCa.haust-AC-5A explained 7.82%—12.72% and 9.68%—15.57% of phenotypic variation,and the physical intervals were 498.67—532.21 Mb and 461.52—486.26 Mb,respectively.QGK.haust-AC-2A.2 explained 8.15%—15.20% of phenotypic variation,with a physical range of 354.61—462.37 Mb.The genetic effect analysis of QGCa.haust-1A,QGCa.haust-AC-5A,and QGK.haust-AC-2A.2 showed that each locus effectively increased the calcium and potassium content in wheat grain.Aggregation effect analysis indicated that the lines with QGCa.haust-1A and QGCa.haust-AC-5A effect loci had highly significantly higher calcium content than those with only a single locus.In summary,three stable loci of grain calcium and potassium content are mapped on chromosomes 1A,2A,and 5A,which could significantly increase calcium and potassium content in wheat grain.

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 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.

In order to further explore the primary QTL loci for grain-related traits in wheat and explore the genetic relationships among grain traits,124 DH populations constructed from wheat varieties AN859 and WN988 with large differences in grain traits were utilized as research materials,The phenotypic values of grain length,grain width,and thousand grains weight were measured in seven environments over two years,respectively,to carry out the multiple regression analysis of grain traits,and QTL detection of grain-related traits was performed based on the 55K microarray data of the DH populations.The results showed that grain width contributed most to thousand grains weight in the multiple regression analysis.QTL localization for grain traits by complete interval mapping,a total of 69 QTLs related to grain traits were detected on 19 chromosomes except chromosome 6D and 7B,including 24 QTLs for thousand grains weight,28 QTLs for grain length,and 17 QTLs for grain width,with phenotypic interpretations of individual QTLs ranging from 6.87% to 27.74%.Among them,grain length-associated Qgl.ahau-7A.1 on chromosome 7A was detected under seven environments and BLUP,with a phenotypic interpretation rate of 9.48%—22.26%,an additive effect of 0.11—0.21 mm,and a physical interval of 4.91 Mb(AX-110430243—AX-110442528),for the new primary effector QTL.Therefore,the Qgl.ahau-7A.1 locus can be used as a region of focus for subsequent fine localization and molecular marker-assisted breeding.