Emmer wheat (Triticum dicoccum, 2n = 4x = 28, AABB), as the ancestral species of common wheat, is a crucial gene donor for improving common wheat against powdery mildew, a destructive wheat disease worldwide. Cultivated emmer wheat accession WL509 exhibits broad and high level of resistance to powdery mildew. Using inheritance analysis, bulked segregated RNA sequencing, and molecular marker detection, we identified a dominant gene, tentatively designated PmWL509, and mapped it to 757.2 to 776.4 Mb interval on chromosome arm 2AL based on the reference genome of wild emmer (v2.0). PmWL509 was then mapped to the Pm4 locus using linked and diagnostic markers of Pm4. Homologous cloning and sequence alignment revealed that PmWL509 shares identical amino acid sequences with Pm4a but exhibits distinct resistance spectra and expression patterns. To explore potential regulatory mechanisms and key genes controlling resistance, 1,024 differential expression genes (DEGs) between resistant and susceptible bulks were annotated and analyzed by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment. Six DEGs in the mapping interval and three pathogenesis-related (PR) genes were screened and evaluated by qRT-PCR when invaded by the Blumeria graminis f. sp. tritici isolate E09, and the result indicated that the two DEGs TRIDC2AG078910 and TRIDC2AG081650 and the two PR genes PR5 and PR9 could be considered to play a key role in the resistant pathway of PmWL509. The diagnostic marker JS717/JS718 was confirmed to be available for efficiently transferring PmWL509 into different wheat backgrounds.

Common wheat (Triticum aestivum L.) is a vital source of nutrition for human consumption. However, wheat production is significantly threatened by various diseases, such as powdery mildew, a widespread fungal disease caused by Blumeria graminis f. sp. tritici (Bgt). Utilizing and identifying resistance genes and elucidating the molecular mechanisms underlying this resistance are the most effective and sustainable ways to fight this disease. Lxd-682, a cultivated emmer wheat accession, exhibited resistance to 12 out of 13 tested Bgt isolates at the seedling stage. Genetic analysis revealed that this resistance is conferred by a single dominant gene, tentatively designated as PmLxd-682. Molecular mapping positioned PmLxd-682 between the markers WGRE77413 and WGRC1096, with the Pm4-diagnostic marker JS717/JS718 co-segregating. Homology-based cloning and sequence alignment further confirmed that PmLxd-682 is identical to Pm4a. qRT-PCR analysis showed that the alternative splicing PmLxd-682-V2 exhibited higher expression level than that of PmLxd-682-V1 post-Bgt invasion, suggesting its prominent role in fighting Bgt invasion. Additionally, four pathogenesis-related (PR) genes were significantly up-regulated in both Lxd-682 and susceptible parent Langdon upon infection, revealing possibly unimportant roles in resistance pathway. Furthermore, 1,567 differentially expressed genes (DEGs) between resistant and susceptible bulks were identified through BSR-Seq, with 490 ones located within the candidate interval on chromosome 2AL, and potential biological processes associated with resistance were enriched via gene ontology (GO) and kyoto encyclopedia of genes and genomes (KEGG) pathway analysis. To verify the potential regulatory genes, three key genes, TRITD2 Av1G294940, TRITD2 Av1G036490 and TRITD2 Av1G295220 all encoding disease resistance protein, were selected from six candidates via qRT-PCR following post-Bgt invasion. Molecular markers JS717/JS718 and WGRC1096 were confirmed to be available for marker-assisted selection (MAS) of PmLxd-682 in breeding practices. The study identified key genetic intervals and genes involved in the resistance of a cultivated emmer wheat accession Lxd-682 to powdery mildew. These findings significantly advance our understanding of plant-pathogen interactions and establish a solid foundation for future genetic and functional studies aimed at improving disease resistance in crops.

The impact of sowing date on wheat starch digestibility remains incompletely understood, particularly regarding its fine molecular architecture (chain-length distribution and molecular weight) and the transcriptional regulation of starch synthase genes. This study systematically examined the effects of normal and delayed sowing on starch digestibility, granule morphology, chain-length distribution, crystalline structure, molecular weight, expression of eight key starch synthase genes, and functional characteristics. Delayed sowing elicited cultivar-specific alterations in gene expression, suppressing short amylopectin chains and long amylose chains while promoting long amylopectin chains, thereby increasing overall molecular weight. These structural modifications enhanced crystallinity and compacted the amorphous zone. All four wheat cultivars maintained yield while improving starch quality under delayed sowing. These results provide a mechanistic framework for optimizing showing schedules to enhance starch functionality under climate change.

Blumeria graminis f. sp. tritici (Bgt), the causal agent of wheat powdery mildew, poses a significant threat to global wheat production. In this study, we identified and characterized a broad-spectrum powdery mildew resistance gene, PmL709, in a resistant cultivated emmer wheat (Triticum dicoccum) accession: L709. Using bulked segregant RNA sequencing (BSR-Seq) analysis and molecular markers, PmL709 was mapped to a 1.7 cM interval on chromosome arm 2BS, flanked by markers Xdw05/YTU95-04/YTU95-06/YTU95-08/Xdw10/Xdw11 and YTU692B-094, corresponding to a 21.82–25.94 Mb physical interval (cv. Svevo), using the segregated population crossed by L709 and a susceptible durum wheat cultivar, Langdon. Referring to the origin, the resistance spectra, and the physical position with known resistance genes on chromosome arm 2BS, PmL709 was likely to be an allele of Pm68. Transcriptomic analysis revealed 3923 differentially expressed genes (DEGs) between resistant and susceptible bulks, enriched in pathways such as phenylpropanoid biosynthesis, MAPK signaling, and plant–pathogen interactions. qRT-PCR validated the differential expression of nine candidate genes within the PmL709 interval, highlighting their potential roles in disease resistance. The flanking markers could accurately trace the presence of PmL709 from resistant accession L709 in a survey of 46 susceptible wheat accessions. These findings provide valuable insights into the genetic and molecular mechanisms of powdery mildew resistance in wheat and offer practical tools for marker-assisted breeding to develop resistant cultivars.

Powdery mildew, caused by Blumeria graminis f. sp. tritici (Bgt), is one of the most destructive fungal diseases threatening global wheat production. Exploring powdery mildew resistance (Pm) gene(s) and dissecting the molecular mechanism of the host resistance are critical to effectively and reasonably control this disease. Durum wheat (Triticum turgidum L. var. durumDesf.) is an important gene donor for wheat improvement against powdery mildew. In this study, a resistant durum wheat accession W762 was used to investigate its potential resistance component(s) and profile its expression pattern in responding to Bgt invasion using bulked segregant RNA-Seq (BSR-Seq) and further qRT-PCR verification. Genetic analysis showed that the powdery mildew resistance in W762 did not meet monogenic inheritance and complex genetic model might exist within the population of W762 × Langdon (susceptible durum wheat). After BSR-Seq, 6,196 consistently different single nucleotide polymorphisms (SNPs) were called between resistant and susceptible parents and bulks, and among them, 763 SNPs were assigned to the chromosome arm 7B. Subsequently, 3,653 differentially expressed genes (DEGs) between resistant and susceptible parents and bulks were annotated and analyzed by Gene Ontology (GO), Cluster of Orthologous Groups (COG), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment. The potential regulated genes were selected and analyzed their temporal expression patterns following Bgt inoculation. As a result, nine disease-related genes showed distinctive expression profile after Bgt invasion and might serve as potential targets to regulate the resistance against powdery mildew in W762. Our study could lay a foundation for analysis of the molecular mechanism and also provide potential targets for the improvement of durable resistance against powdery mildew.

BackgroundBread wheat is one of the most important food crops associated with ensuring food security and human nutritional health. The starch quality is an important index of high-quality wheat. It is affected by a complex series of factors; among which, suitable sowing time is a key factor.Aim and methodsTo analyze the integrative effects of sowing time on the starch quality of high-quality wheat, in the present study, we selected a high-quality bread wheat cultivar Jinan 17 and investigated the effect of different sowing times on the starch properties and the related genes by analyzing X-ray diffraction patterns, apparent amylose content, thermal properties, pasting properties, in vitro starch digestibility, and qRT-PCR. Meanwhile, we also investigated the agronomic and yield performance that may be associated with the starch properties.ResultsDelayed sowing had little effect on starch crystalline morphology, but there was a tendency to reduce the formation of crystals within wheat starch granules: (1) delayed sowing for 15 days altered the thermal properties of starch, including onset, peak and termination temperatures, and enthalpy changes; (2) delayed sowing for 30 days changed the thermal characteristics of starch relatively insignificant; (3) significant differences in pasting characteristics occurred: peak viscosity and hold-through viscosity increased, while final viscosity, breakdown viscosity, and setback viscosity tended to increase and then decrease, suggesting that delayed sowing caused changes in the surface of the starch granules resulting in a decrease in digestibility. Analysis of related genes showed that several key enzymes in starch biosynthesis were significantly affected by delayed sowing, leading to a reduction in apparent straight-chain starch content. In addition to starch properties, thousand-kernel weight also increased under delayed sowing conditions compared with normal sowing.ConclusionThe impact of delayed sowing on starch quality is multifaceted and complex, from the fine structure, and functional properties of the starch to the regulation of key gene expression. Our study holds significant practical value for optimizing wheat planting management and maximizing the potential in both quality and yield.

Wheat variety Yannong 999（ YN999） shows stably high yield potential with strong environment adaptability. Unlocking its genetic basis and key chromosomal regions underlying high yield performance will provide theoretical support for the further application. In this study, a 55K wheat SNP array was used for genotyping the YN999, its 46 derived varieties（ lines） and a natural mapping population containing 243 wheat varieties（lines）. The genetic effects of the key chromosomal segments undergone strong selection was elucidated. The genetic cause of high-yielding potential in YN999 was dissected based on the composition of excellent alleles underlying the three yield components. The characteristics of high thousand kernel weight were preferentially selected and present in the derived varieties（lines）. Genotyping using the wheat 55K SNP array revealed that the average genetic similarity coefficient of YN999 if compared to 46 derived varieties（ lines） was 0.87. The genetic contribution of YN999 to its derived varieties（lines） of F3, F5, F6 and F7 were 84.94%, 86.19%, 86.67% and 87.65%, respectively. A total of 222 segments of YN999 with over 95% transmission rate were detected in the offspring of YN999, and the length of the segment varied from 5.04 Mb to 108.75 Mb, among which 2A contained the longest segment with high frequency selection, being 483.37 Mb, and 7D contained the shortest of 13.84 Mb. A total of 135 identified QTL related to yield traits were coincided with the 222 high-frequency selection regions, with 80, 48 and 7 QTL in the A, B and D genome, respectively. A total of 1195, 267, 790 and 678 significant SNPs, which were correlated with yield per plant, kernel number per spike, 1000-grain weight and spike number per plant, respectively, were detected by single marker QTL analysis using a natural mapping population. Among those, approximately 84.02%, 51.69%, 94.18% and 13.42% alleles contributing to the higher yield performance were identified from YN999. These results indicate that YN999 has enriched the superior alleles of yield per plant and 1000-grain weight, which might be the important genetic basis for the high and stable yield in YN999. This study provided theoretical reference in application of YN999 as key parent in molecular breeding programs, and identification and cloning of the genes with high yield performance.

Powdery mildew of wheat (Triticum aestivum), caused by Blumeria graminis f.sp. tritici (Bgt), is a destructive disease that seriously threatens the yield and quality of its host. Identifying resistance genes is the most attractive and effective strategy for developing disease-resistant cultivars and controlling this disease. In this study, a wheat breeding line Yannong 99102-06188 (YN99102), an elite derivative line from the same breeding process as the famous wheat cultivar Yannong 999, showed high resistance to powdery mildew at the whole growth stages. Genetic analysis was carried out using Bgt isolate E09 and a population of YN99102 crossed with a susceptible parent Jinhe 13–205 (JH13–205). The result indicated that a single recessive gene, tentatively designated pmYN99102, conferred seedling resistance to the Bgt isolate E09. Using bulked segregant exome capture sequencing (BSE-Seq), pmYN99102 was physically located to a ~33.7 Mb (691.0–724.7 Mb) interval on the chromosome arm 2BL, and this interval was further locked in a 1.5 cM genetic interval using molecular markers, which was aligned to a 9.0 Mb physical interval (699.2–708.2 Mb). Based on the analysis of physical location, origin, resistant spectrum, and inherited pattern, pmYN99102 differed from those of the reported powdery mildew (Pm) resistance genes on 2BL, suggesting pmYN99102 is most likely a new Pm gene/allele in the targeted interval. To transfer pmYN99102 to different genetic backgrounds using marker-assisted selection (MAS), 18 closely linked markers were tested for their availability in different genetic backgrounds for MAS, and all markers expect for YTU103-97 can be used in MAS for tracking pmYN99102 when it transferred into those susceptible cultivars.

为了明确测墒补灌对冬小麦产量和干物质积累的影响,以高产优质冬小麦'烟农999'为材料,试验设置5个水分处理:W0全生育期不浇水,Wck为传统灌溉处理(对照),W70、W75、W80为测墒补灌处理,于拔节期和开花期分别补灌至土壤相对含水量的70％、75％、80％.结果表明:(1)各处理之间相比较,W75籽粒产量和水分利用效率最高,分别为11438.85 kg/hm2、25.78 kg/(hm2·mm),比传统灌溉处理提高了12.12％、21.2％.(2)W75处理开花期和灌浆期的叶面积指数、灌浆期的旗叶净光合速率、开花期干物质转移率、灌浆期营养器官对籽粒的贡献率显著高于其他处理.综合分析,本试验条件下W75是'烟农999'获得高产高水分利用效率的灌溉方案.

为选育出适宜黄淮冬麦区种植的高产、抗旱、稳产、广适的小麦新品种,采用航天诱变育种与常规育种技术相结合的方法,选育出小麦新品种烟农836,于2010和2014年分别通过山东省和国家农作物品种审定委员会审定.该品种产量水平高、稳产性好,在山东省小麦旱地区域试验中比对照鲁麦21号增产4.45％～9.74％;国家黄淮冬麦区旱肥地区域试验中比对照洛旱7号增产5.3％～6.7％,抗旱性中等,抗病性好,品质优良.烟农836可作为高产抗旱品种在黄淮麦区旱肥地大面积推广应用.

Summary Heat stress (HS) causes substantial damages to worldwide crop production. As a cool season crop, wheat (Triticum aestivum) is sensitive to HS‐induced damages. To support the genetic improvement of wheat HS tolerance (HST), we conducted fine mapping of TaHST1, a locus required for maintaining wheat vegetative and reproductive growth under elevated temperatures. TaHST1 was mapped to the distal terminus of 4AL chromosome arm using genetic populations derived from two BC6F6 breeding lines showing tolerance (E6015‐4T) or sensitivity (E6015‐3S) to HS. The 4AL region carrying TaHST1 locus was approximately 0.949 Mbp and contained the last 19 high confidence genes of 4AL according to wheat reference genome sequence. Resequencing of E6015‐3S and E6015‐4T and haplotype analysis of 3087 worldwide wheat accessions revealed heightened deletion polymorphisms in the distal 0.949 Mbp region of 4AL, which was confirmed by the finding of frequent gene losses in this region in eight genome‐sequenced hexaploid wheat cultivars. The great majority (86.36%) of the 3087 lines displayed different degrees of nucleotide sequence deletions, with only 13.64% of them resembling E6015‐4T in this region. These deletions can impair the presence and/or function of TaHST1 and surrounding genes, thus rendering global wheat germplasm vulnerable to HS or other environmental adversities. Therefore, conscientious and urgent efforts are needed in global wheat breeding programmes to optimize the structure and function of 4AL distal terminus by ensuring the presence of TaHST1 and surrounding genes. The new information reported here will help to accelerate the ongoing global efforts in improving wheat HST.

为全面了解超高产小麦品种‘烟农999’的特征特性,为超高产品种的选育提供借鉴,对‘烟农999’的育种目标、选育过程、特征特性以及选育策略进行了分析。结果表明:‘烟农999’产量表现突出,在小麦高产创建中实打12255.0 kg/hm~2,创山东省小麦单产最高纪录和农业部专家实打验收全国冬小麦单产最高纪录;品质优良,在国家黄淮南片冬水组区域试验中连续2年达到国家强筋小麦标准;适应性广,先后通过山东和国家审定;田间综合抗性好。超高产品种的选育要加强种质创新和多种育种方法的应用,注意高穗粒重的选择,提高生物产量,注重产量与品质的协同提高。

正确选用亲本、合理配制组合是小麦育种取得成效的基础.分析了优良组合"鲁麦14/豫麦13"双亲的突出特点和遗传特性,"鲁麦14/豫麦13"的正反交组合,由江苏、山西、安徽的5个育种单位育成并通过审定品种10个,其中国家审定3次,通过黄淮南片和3省14次审(认)定,充分体现了这一组合的育种价值.讨论了各育种单位推荐最优组合开展多生态选择和异地鉴定的重要性.

烟农999(原代号:烟99102)是烟台市农科院选育的超高产优质广适性小麦新品种,2011年和2016年分别通过山东省和国家审定.该品种增产潜力大,曾在2014年小麦高产创建中亩产817.0 kg,创山东省小麦单产最高纪录和农业部专家实打验收全国冬小麦单产最高纪录.本文作者对烟农999的主要特性、产量表现、品质表现、抗性表现及超高产栽培技术进行了总结,以期为超高产小麦的选育和推广提供借鉴.

The experiment was conducted to study the physiological characteristics of flag leaf of four wheat varieties(Yannong 5158 and its parents Lumai 14,Yannong 15,Yanhangxuan 2)in pots.The results showed that the photosynthetic rate(Pn)of flag leaf of Yannong 5158 and its parents reached their maximal values during anthesis stage,and then declined gradually.The Pnwas significant difference among different wheat varieties during late growth stage.The Pnof Yannong 5158 was higher than those of its parents.Compared with the parents of Yannong 5158,the activities of antioxidant enzymes SOD,POD and CAT in flag leaf of Yannong 5158 declined slowly and maintained the higher level at late growth stage.The activity trends of SOD,POD and APX in flag leaves of Yannong 5158 and its parents increased firstly and then decreased.Yannong 5158 had higher APX activity in flag leaves than its parents during 7to 28 dafter anthesis.The soluble protein content in flag leaf of Yannong 5158 was higher than those of its parents,and MDA content of Yannong 5158 was lower than those of its parents.This study indicated that the characteristics of Yannong 5158 with slow leaf senescence,high photosynthetic rate and strong resistance,may be related to its lower MDA content,higher antioxidant enzyme activities and soluble protein content at late growth stage.

烟农836是烟台市农业科学研究院利用返回式卫星搭载以山农721511为母本、鲁麦21为父本有性杂交选育出的烟9292高代品系,经太空处理8 d后再经系统选育而成的高产、抗旱小麦新品种。2010年通过山东省审定委员会审定,2011年和2012年被列入山东省小麦主导品种。

The field plot experiment was used to study the effects of topdressing nitrogen fertilizer on yield and quality of wheat variety Yannong 5158. The results showed that topdressing nitrogen fertilizer had an apparent influence on effective spike number,and the treatment of basal application of 70% nitrogen and topdressing 30% nitrogen at jointing stage had the highest yield. The grain protein and wet gluten contents and stable time could be significantly improved by delaying nitrogen application stage,and increased with the increase of topdressing nitrogen proportion. With the delay of nitrogen application stage,wheat flour whiteness declined and then raised. Comprehensively considering yield,quality and flour whiteness,the treatment of basal application of 70% nitrogen and topdressing 30% nitrogen at jointing stage had higher yield and quality and better flour whiteness.

In recent years,the wheat production increased year by year in China,but it still failed to meet people's demand for wheat.Establishing super-high yield of wheat had important significance to satisfy people's needs and guarantee the grain security in China.In this paper,the varieties,climate,cultivation patterns and other influencing factors were discussed in order to provide reference for wheat super-high-yielding establishment.

In this paper,the research advances on genetic and non-genetic factors affecting wheat whiteness,new high whiteness wheat breeding and genetic improvement were reviewed.Then the breeding prospect of high whiteness wheat was analyzed.