Virtual Issue

    麦类遗传育种合辑Triticeae Crops Genetics · Breeding · Germplasm Resources

    Default Latest Most Read
    Please wait a minute...
    For Selected: Toggle Thumbnails
    A major and stable QTL for wheat spikelet number per spike validated in different genetic backgrounds
    DING Pu-yang, MO Zi-qiang, TANG Hua-ping, MU Yang, DENG Mei, JIANG Qian-tao, LIU Ya-xi, CHEN Guang-deng, CHEN Guo-yue, WANG Ji-rui, LI Wei, QI Peng-fei, JIANG Yun-feng, KANG Hou-yang, YAN Gui-jun, Wei Yu-ming, ZHENG You-liang, LAN Xiu-jin, MA Jian
    2022, 21 (6): 1551-1562.   DOI: 10.1016/S2095-3119(20)63602-4
    Abstract201)      PDF in ScienceDirect      
    The spikelet number per spike (SNS) contributes greatly to grain yield in wheat.  Identifying various genes that control wheat SNS is vital for yield improvement.  This study used a recombinant inbred line population genotyped by the Wheat55K single-nucleotide polymorphism array to identify two major and stably expressed quantitative trait loci (QTLs) for SNS.  One of them (QSns.sau-2SY-2D.1) was reported previously, while the other (QSns.sau-2SY-7A) was newly detected and further analyzed in this study.  QSns.sau-2SY-7A had a high LOD value ranging from 4.46 to 16.00 and explained 10.21–40.78% of the phenotypic variances.  QSns.sau-2SY-7A was flanked by the markers AX-110518554 and AX-110094527 in a 4.75-cM interval on chromosome arm 7AL.  The contributions and interactions of both major QTLs were further analyzed and discussed.  The effect of QSns.sau-2SY-7A was successfully validated by developing a tightly linked kompetitive allele specific PCR marker in an F2:3 population and a panel of 101 high-generation breeding wheat lines.  Furthermore, several genes including the previously reported WHEAT ORTHOLOG OF APO1 (WAPO1), an ortholog of the rice gene ABERRANT PANICLE ORGANIZATION 1 (APO1) related to SNS, were predicted in the interval of QSns.sau-2SY-7A.  In summary, these results revealed the genetic basis of the multi-spikelet genotype of wheat line 20828 and will facilitate subsequent fine mapping and breeding utilization of the major QTLs.
    Reference | Related Articles | Metrics
    Influence of high-molecular-weight glutenin subunit deletions at the Glu-A1 and Glu-D1 loci on protein body development, protein components and dough properties of wheat (Triticum aestivum L.)
    LIU Da-tong, ZHANG Xiao, JIANG Wei, LI Man, WU Xu-jiang, GAO De-rong, BIE Tong-de, LU Cheng-bin
    2022, 21 (7): 1867-1876.   DOI: 10.1016/S2095-3119(21)63605-5
    Abstract196)      PDF in ScienceDirect      
    High-molecular-weight glutenin subunits (HMW-GSs) play a critical role in determining the viscoelastic properties of wheat.  As the organelle where proteins are stored, the development of protein bodies (PBs) reflects the status of protein synthesis and also affects grain quality to a great extent.  In this study, with special materials of four near-isogenic lines in a Yangmai 18 background we created, the effects of Glu-A1 and Glu-D1 loci deletions on the development and morphological properties of the protein body, protein components and dough properties were investigated.  The results showed that the deletion of the HMW-GS subunit delayed the development process of the PBs, and slowed the increases of volume and area of PBs from 10 days after anthesis (DAA) onwards.  In contrast, the areas of PBs at 25 DAA, the middle or late stage of endosperm development, showed no distinguishable differences among the four lines.  Compared to the wild type and single null type in Glu-A1, the ratios of HMW-GSs to low-molecular-weight glutenin subunits (LMW-GSs), glutenin macropolymer (GMP) content, mixograph parameters as well as extension parameters decreased in the single null type in Glu-D1 and double null type in Glu-A1 and Glu-D1, while the ratios of gliadins (Gli)/glutenins (Glu) in those types increased.  The absence of Glu-D1 subunits decreased both dough strength and extensibility significantly compared to the Glu-A1 deletion type.  These results provide a detailed description of the effect of HMW-GS deletion on PBs, protein traits and dough properties, and contribute to the utilization of Glu-D1 deletion germplasm in weak gluten wheat improvement for use in cookies, cakes and southern steamed bread in China and liquor processing. 
    Reference | Related Articles | Metrics
    Variations in the quality parameters and gluten proteins in synthetic hexaploid wheats solely expressing the Glu-D1 locus
    DAI Shou-fen, CHEN Hai-xia, LI Hao-yuan, YANG Wan-jun, ZHAI Zhi, LIU Qian-yu, LI Jian, YAN Ze-hong
    2022, 21 (7): 1877-1885.   DOI: 10.1016/S2095-3119(21)63651-1
    Abstract141)      PDF in ScienceDirect      
    This study evaluated the quality potential of seven synthetic hexaploid wheats (2n=6x=42, AABBDD) expressing only allelic variation at Glu-D1 of Aegilops tauschii (SHWSD).  Major quality parameters related to dough strength, gluten proteins (including high-molecular-weight glutenin subunits (HMW-GS) and low-molecular-weight glutenin subunits (LMW-GS), gliadins), and their ratios between SHWSD and the weak gluten wheat control Chuannong 16 (CN16) were measured in at least three environments (except STD7).  The zeleny sedimentation value (ZSV), dough development time (DDT), dough stability time (DST), and farinograph quality number (FQN) of SHWSD were considered stable under different environments, with their respective ranges being 8.00–17.67 mL, 0.57–1.50 min, 0.73–1.80 min, and 9.50–27.00.  The ZSV, DDT, DST, and FQN of SHWSD were smaller than those of CN16, suggesting that SHWSD had a weaker dough strength than CN16.  Although SHWSD had a lower gluten index than CN16, its wet and dry gluten contents were similar to or even higher than those of CN16 in all environments tested.  The protein content of grains (12.81–18.21%) and flours (14.20–20.31%) in SHWSD was higher than that in CN16.  The amount of HMW-GS in SHWSD sharply decreased under the expression of fewer HMW-GS genes, and the LMW-GS, gliadins, and total glutenins were simultaneously increased in SHWSD in comparison with CN16.  Moreover, SHWSD had higher ratios of LMW-GS/glutenin and gliadin/glutenin but a lower ratio of HMW-GS/glutenin than CN16.  These results provide necessary information for the utilization of SHWSD in weak-gluten wheat breeding.
    Reference | Related Articles | Metrics
    Identification and validation of novel loci associated with wheat quality through a genome-wide association study
    PU Zhi-en, YE Xue-ling, LI Yang, SHI Bing-xin, GUO Zhu, DAI Shou-fen, MA Jian, LIU Ze-hou, JIANG Yun-feng, LI Wei, JIANG Qian-tao, CHEN Guo-yue, WEI Yu-ming, ZHENG You-liang
    2022, 21 (11): 3131-3147.   DOI: 10.1016/j.jia.2022.08.085
    Abstract162)      PDF in ScienceDirect      
    Understanding the genetic basis of quality-related traits contributes to the improvement of grain protein concentration (GPC), grain starch concentration (GSC), and wet gluten concentration (WGC) in wheat, a genome-wide association study (GWAS) based on a mixed linear model (MLM) was performed on the 236 wheat accessions including 160 cultivars and 76 landraces using 55K single nucleotide polymorphism (SNP) array in multiple environments. A total of twelve stable QTL/SNPs were identified to control different quality traits in this populations at least two environments under stripe rust stress; three, seven and two QTLs associated with GPC, GSC, and WGC were characterized respectively and located on chromosomes 1B, 1D, 2A, 2B, 2D, 3B, 3D, 5D, and 7D with the range of phenotypic variation explained (PVE) from 4.2 to 10.7%. Compared with the previously reported QTLs/genes, five QTLs (QGsc.sicau-1BL, QGsc.sicau-1DS, QGsc.sicau-2DL.1, QGsc.sicau-2DL.2, QWgc.sicau-5DL) were potentially novel. KASP markers for SNPs AX-108770574 and AX-108791420 on chromosome on 5D associated with wet gluten concentration were successfully developed. Phenotype of the cultivars containing the A-allele in AX-108770574 and T-allele in AX-108791420 were extremely significantly (P<0.01) higher than that of the landraces containing the G-allele or C-allele of wet gluten concentration in each of the environments. The developed and validated KASP markers could be utilized in molecular breeding aiming to improve the quality in wheat.
    Reference | Related Articles | Metrics
    Genetic dissection of the grain filling rate and related traits through linkage analysis and genome-wide association study in bread wheat
    YU Hai-xia, DUAN Xi-xian, SUN Ai-qing, SUN Xiao-xiao, ZHANG Jing-juan, SUN Hua-qing, SUN Yan-yan, NING Tang-yuan, TIAN Ji-chun, WANG Dong-xue, LI Hao, FAN Ke-xin, WANG Ai-ping, MA Wu-jun, CHEN Jian-sheng
    2022, 21 (10): 2805-2817.   DOI: 10.1016/j.jia.2022.07.032
    Abstract161)      PDF in ScienceDirect      

    Wheat grain yield is generally sink-limited during grain filling.  The grain-filling rate (GFR) plays a vital role but is poorly studied due to the difficulty of phenotype surveys.  This study explored the grain-filling traits in a recombinant inbred population and wheat collection using two highly saturated genetic maps for linkage analysis and genome-wide association study (GWAS).  Seventeen stable additive quantitative trait loci (QTLs) were identified on chromosomes 1B, 4B, and 5A.  The linkage interval between IWB19555 and IWB56078 showed pleiotropic effects on GFR1, GFRmax, kernel length (KL), kernel width (KW), kernel thickness (KT), and thousand kernel weight (TKW), with the phenotypic variation explained (PVE) ranging from 13.38% (KW) to 33.69% (TKW).  198 significant marker-trait associations (MTAs) were distributed across most chromosomes except for 3D and 4D.  The major associated sites for GFR included IWB44469 (11.27%), IWB8156 (12.56%) and IWB24812 (14.46%).  Linkage analysis suggested that IWB35850, identified through GWAS, was located in approximately the same region as QGFRmax2B.3-11, where two high-confidence candidate genes were present.  Two important grain weight (GW)-related QTLs colocalized with grain-filling QTLs.  The findings contribute to understanding the genetic architecture of the GFR and provide a basic approach to predict candidate genes for grain yield trait QTLs.

    Reference | Related Articles | Metrics
    Identification of QTL and underlying genes for root system architecture associated with nitrate nutrition in hexaploid wheat
    Marcus GRIFFITHS, Jonathan A. ATKINSON, Laura-Jayne GARDINER, Ranjan SWARUP, Michael P. POUND, Michael H. WILSON, Malcolm J. BENNETT, Darren M. WELLS
    2022, 21 (4): 917-932.   DOI: 10.1016/S2095-3119(21)63700-0
    Abstract120)      PDF in ScienceDirect      
    The root system architecture (RSA) of a crop has a profound effect on the uptake of nutrients and consequently the potential yield.  However, little is known about the genetic basis of RSA and resource adaptive responses in wheat (Triticum aestivum L.).  Here, a high-throughput germination paper-based plant phenotyping system was used to identify seedling traits in a wheat doubled haploid mapping population, Savannah×Rialto.  Significant genotypic and nitrate-N treatment variation was found across the population for seedling traits with distinct trait grouping for root size-related traits and root distribution-related traits.  Quantitative trait locus (QTL) analysis identified a total of 59 seedling trait QTLs.  Across two nitrate treatments, 27 root QTLs were specific to the nitrate treatment.  Transcriptomic analyses for one of the QTLs on chromosome 2D, which was found under low nitrate conditions, revealed gene enrichment in N-related biological processes and 28 differentially expressed genes with possible involvement in a root angle response.  Together, these findings provide genetic insight into root system architecture and plant adaptive responses to nitrate, as well as targets that could help improve N capture in wheat.
    Reference | Related Articles | Metrics
    TaIAA15 genes regulate plant architecture in wheat
    LI Fu, YAN Dong, GAO Li-feng, LIU Pan, ZHAO Guang-yao, JIA Ji-zeng, REN Zheng-long
    2022, 21 (5): 1243-1252.   DOI: 10.1016/S2095-3119(20)63480-3
    Abstract273)      PDF in ScienceDirect      
    Bread wheat (Triticum aestivum L.) is one of the most important staple crops worldwide.  The phytohormone auxin plays critical roles in the regulation of plant growth and development.  However, only a few auxin-related genes have been genetically demonstrated to be involved in the control of plant architecture in wheat thus far.  In this study, we characterized an auxin-related gene in wheat, TaIAA15, and found that its ectopic expression in rice decreased the plant height and increased the leaf angle.  Correlation analysis indicated that TaIAA15-3B was associated with plant height (Ph), spike length (SL) and 1 000-grain weight (TGW) in wheat, and Hap-II of TaIAA15-3B was the most favored allele and selected by modern breeding in China.  This study sheds light on the role of auxin signaling on wheat plant architecture as well as yield related traits.
    Reference | Related Articles | Metrics
    Allele mining of wheat ABA receptor at TaPYL4 suggests neo-functionalization among the wheat homoeologs
    WU Bang-bang, SHI Meng-meng, Mohammad POURKHEIRANDISH, ZHAO Qi, WANG Ying, YANG Chen-kang, QIAO Ling, ZHAO Jia-jia, YAN Su-xian, ZHENG Xing-wei, ZHENG Jun
    2022, 21 (8): 2183-2196.   DOI: 10.1016/S2095-3119(21)63699-7
    Abstract137)      PDF in ScienceDirect      
    ABA receptors (PYR/PYL/RCAR) play a central role in the water loss control of plants.  A previous report indicated that TaPYL4 is a critical gene in wheat that improves grain production under drought conditions and increases water use efficiency.  In this study, we analyzed the sequence polymorphisms and genetic effects of TaPYL4s.  Based on isolated TaPYL4 genes from chromosomes 2A, 2B and 2D, three haplotypes were detected in the promoter region of TaPYL4-2A, and two haplotypes were present in TaPYL4-2B and TaPYL4-2D, respectively.  Marker/trait association analysis indicated that TaPYL4-2A was significantly associated with plant height in 262 Chinese wheat core collection accessions, as well as the drought tolerance coefficient (DTC) for plant height in 239 wheat varieties from Shanxi Province in multiple environments.  However, the frequencies of favored drought-tolerant haplotype TaPYL4-2A-Hap2 were considerably low, accounting for only 10%, and lines with this certain Hap could be reserved in the breeding program.  TaPYL4-2B was significantly associated with grain number, and the favored haplotype TaPYL4-2B-Hap1 was the dominant allele of above 90% in the collection.  For TaPYL4-2D, there were no significant differences in these traits between the two haplotypes in either of the two panels.  These results indicate that variation might lead to functional differentiation among the homoeologs and the haplotypes had undergone artificial selection during breeding.  Two molecular markers developed to distinguish these haplotypes could be used for breeding in water-limited regions.

    Reference | Related Articles | Metrics
    Genetic and agronomic traits stability of marker-free transgenic wheat plants generated from Agrobacterium-mediated co-transformation in T2 and T3 generations
    LIU Hui-yun, WANG Ke, WANG Jing, DU Li-pu, PEI Xin-wu, YE Xing-guo
    2020, 19 (1): 23-32.   DOI: 10.1016/S2095-3119(19)62601-8
    Abstract73)      PDF in ScienceDirect      
    Genetically modified wheat has not been commercially utilized in agriculture largely due to regulatory hurdles associated with traditional transformation methods.  Development of marker-free transgenic wheat plants will help to facilitate biosafety evaluation and the eventual environmental release of transgenic wheat varieties.  In this study, the marker-free transgenic wheat plants previously obtained by Agrobacterium-mediated co-transformation of double T-DNAs vector were identified by fluorescence in situ hybridization (FISH) in the T1 generation, and their genetic stability and agronomic traits were analyzed in T2 and T3 generations.  FISH analysis indicated that the transgene often integrated into a position at the distal region of wheat chromosomes.  Furthermore, we show that the GUS transgene was stably inherited in the marker-free transgenic plants in T1 to T3 generations.  No significant differences in agronomic traits or grain characteristics were observed in T3 generation, with the exception of a small variation in spike length and grains per spike in a few lines.  The selection marker of bar gene was not found in the transgenic plants through T1 to T3 generations.  The results from this investigation lay a solid foundation for the potential application of the marker-free transgenic wheat plants achieved through the co-transformation of double T-DNAs vector by Agrobacterium in agriculture after biosafty evaluation.
    Reference | Related Articles | Metrics
    Biotic and abiotic stress-responsive genes are stimulated to resist drought stress in purple wheat
    LI Xiao-lan, Lü Xiang, WANG Xiao-hong, PENG Qin, ZHANG Ming-sheng, REN Ming-jian
    2020, 19 (1): 33-50.   DOI: 10.1016/S2095-3119(19)62659-6
    Abstract92)      PDF in ScienceDirect      
    Triticum aestivum L. cv. Guizi 1 (GZ1) is a drought-tolerant local purple wheat cultivar.  It is not clear how purple wheat resists drought stress, but it could be related to anthocyanin biosynthesis.  In this study, transcriptome data from drought-treated samples and controls were compared.  Drought slightly reduced the anthocyanin, protein and starch contents of GZ1 grains and significantly reduced the grain weight. Under drought stress, 16 682 transcripts were reduced, 27 766 differentially expressed genes (DEGs) were identified, and 379 DEGs, including DREBs, were related to defense response.  The defense-response genes included response to water deprivation, reactive oxygen, bacteria, fungi, etc.  Most of the structural and regulatory genes in anthocyanin biosynthesis were downregulated, with only TaDFR, TaOMT, Ta5,3GT, and TaMYB-4B1 being upregulated. TaCHS, TaF3H, TaCHI, Ta4CL, and TaF3’H are involved in responses to UV, hormones, and stimulus.  TaCHS-2D1, TaDFR-2D2, TaDFR-7D, TaOMT-5A, Ta5,3GT-1B1, Ta5,3GT-3A, and Ta5,3GT-7B1 connect anthocyanin biosynthesis with other pathways, and their interacting proteins are involved in primary metabolism, genetic regulation, growth and development, and defense responses.  There is further speculation about the defense-responsive network in purple wheat.  The results indicated that biotic and abiotic stress-responsive genes were stimulated to resist drought stress in purple wheat GZ1, and anthocyanin biosynthesis also participated in the drought defense response through several structural genes.
    Reference | Related Articles | Metrics
    Genetic progress in stem lodging resistance of the dominant wheat cultivars adapted to Yellow-Huai River Valleys Winter Wheat Zone in China since 1964
    ZHANG Hong-jun, LI Teng, LIU Hong-wei, MAI Chun-yan, YU Guang-jun, LI Hui-li, YU Li-qiang, MENG Ling-zhi, JIAN Da-wei, YANG Li, LI Hong-jie, ZHOU Yang
    2020, 19 (2): 438-448.   DOI: 10.1016/S2095-3119(19)62627-4
    Abstract101)           
    Analysis of genetic progress for lodging-related traits provides important information for further improvement of lodging resistance.  Forty winter wheat cultivars widely grown in the Yellow-Huai River Valleys Winter Wheat Zone (YHWZ) of China during the period of 1964–2015 were evaluated for several lodging-related traits in three cropping seasons.  Plant height, height at center of gravity, length of the basal second internode, and lodging index decreased significantly in this period, and the average annual genetic gains for these traits were –0.50 cm or –0.62%, –0.27 cm or –0.60%, –0.06 cm or –0.63%, and –0.01 or –0.94%, respectively.  Different from other traits, stem strength showed a significant increasing trend with the breeding period, and the annual genetic gains were 0.03 N or 0.05%.  Correlation analysis showed that lodging index was positively correlated with plant height, height at center of gravity, and length of the basal second internode, but negatively correlated with stem strength.  Meanwhile, significantly positive correlations were observed between plant height, height at center of gravity, and length of the basal first and second internodes.  By comparison with the wild types, dwarfing genes had significant effects on all lodging-related traits studied except for length of the basal first internode and stem strength.  Principle component analysis demonstrated that plant height and stem strength were the most important factors influencing lodging resistance.  Clustering analysis based on the first two principle components further indicated the targets of wheat lodging-resistant breeding have changed from reducing plant height to strengthening stem strength over the breeding periods.  This study indicates that the increase of stem strength is vital to improve lodging resistance in this region under the high-yielding condition when plant height is in an optimal range.
     
    Reference | Related Articles | Metrics
    Identification of QTL for adult plant resistance to stripe rust in bread wheat line C33
    LUO Jiang-tao, ZHENG Jian-min, WAN Hong-shen, YANG Wu-yun, LI Shi-zhao, PU Zong-jun
    2020, 19 (3): 624-631.   DOI: 10.1016/S2095-3119(19)62638-9
    Abstract124)      PDF in ScienceDirect      
    Stripe rust, caused by Puccinia striiformis f. sp. tritici, is a serious disease in bread wheat (Triticum aestivum L.).  Identification and use of adult plant resistance (APR) resources are important for stripe rust resistance breeding.  Bread wheat line C33 is an exotic germplasm that has shown stable APR to stripe rust for more than 10 years in Sichuan Province of China.  Here, 183 recombinant inbred lines (RILs) derived from the cross between C33 and a susceptible line X440 were genotyped with diversity arrays technology (DArT) markers to identify resistance quantitative trait locus (QTL).  Field trials were conducted in five years at Chengdu and Xindu of Sichuan Province, using maximum disease severity (MDS) as stripe rust reaction phenotypes.  A total of four quantitative trait loci (QTLs) were detected, respectively designed as QYr.saas-3AS, QYr.saas-5AL, QYr.saas-5BL, and QYr.saas-7DS, explaining 4.14–15.21% of the phenotypic variances.  QYr.saas-5BL and QYr.saas-7DS were contributed by C33.  However, the level for stripe rust resistance contributed by them was not strong as C33, suggesting the presence of other unidentified QTLs in C33.  QYr.saas-7DS corresponded to Yr18 and QYr.saas-5BL remains to be formally named.  The RIL lines carrying combinations QYr.saas-5AL, QYr.saas-5BL, and QYr.saas-7DS showed comparability resistance with C33.  The present study provides resources to pyramid diverse genes into locally adapted elite germplasm to improve the stripe rust resistance of bread wheat.
    Reference | Related Articles | Metrics
    Molecular detection of the powdery mildew resistance genes in winter wheats DH51302 and Shimai 26
    QU Yun-feng, WU Pei-pei, HU Jing-huang, CHEN Yong-xing, SHI Zhan-liang, QIU Dan, LI Ya-hui, ZHANG Hong-jun, ZHOU Yang, YANG Li, LIU Hong-wei, ZHU Tong-quan, LIU Zhi-yong, ZHANG Yan-ming, LI Hong-jie
    2020, 19 (4): 931-940.   DOI: 10.1016/S2095-3119(19)62644-4
    Abstract84)      PDF in ScienceDirect      
    Resistance to powdery mildew is an important trait of interest in many wheat breeding programs.  The information on genes conferring resistance to powdery mildew in wheat cultivars is useful in parental selection.  Winter wheat breeding line DH51302 derived from Liangxing 99 and cultivar Shimai 26 derived from Jimai 22 showed identical infection patterns against 13 isolates of Blumeria graminis f. sp. tritici (Bgt) that causes wheat powdery mildew.  DH51302 and Shimai 26 were crossed to a powdery mildew susceptible cultivar Zhongzuo 9504 and the F2:3 families were used in molecular localization of the resistance genes.  Fourteen polymorphic markers, which were linked to Pm52 from Liangxing 99, were used to establish the genetic linkage maps for the resistance genes PmDH51302 and PmSM26 in DH51302 and Shimai 26, respectively.  These genes were placed in the same genetic interval where Pm52 resides.  Analysis of gene-linked molecular markers indicated that PmDH51302 and PmSM26 differed from other powdery mildew resistance genes on chromosome arm 2BL, such as Pm6, Pm33, Pm51, MlZec1, MlAB10, and Pm64.  Based on the results of reaction patterns to different Bgt isolates and molecular marker localization, together with the pedigree information, DH51302 and Shimai 26 carried the same gene, Pm52, which confers their resistance to powdery mildew.
     
    Reference | Related Articles | Metrics
    Heterologous expression of the ThIPK2 gene enhances drought resistance of common wheat
    ZHANG Shu-juan, LI Yu-lian, SONG Guo-qi, GAO Jie, ZHANG Rong-zhi, LI Wei, CHEN Ming-li, LI Gen-ying
    2020, 19 (4): 941-952.   DOI: 10.1016/S2095-3119(19)62714-0
    Abstract92)      PDF in ScienceDirect      
    ThIPK2 is an inositol polyphosphate kinase gene cloned from Thellungiella halophila that participates in diverse cellular processes.  Drought is a major limiting factor in wheat (Triticum aestivum L.) production.  The present study investigated whether the application of the ThIPK2 gene could increase the drought resistance of transgenic wheat.  The codon-optimized ThIPK2 gene was transferred into common wheat through Agrobacterium-mediated transformation driven by either a constitutive maize ubiquitin promoter or a stress-inducible rd29A promoter from Arabidopsis.  Molecular characterization confirmed the presence of the foreign gene in the transformed plants.  The transgenic expression of ThIPK2 in wheat led to significantly improve drought tolerance compared to that observed in control plants.  Compared to the wild type (WT) plants, the transgenic plants showed higher seed germination rates, better developed root systems, a higher relative water content (RWC) and total soluble sugar content, and less cell membrane damage under drought stress conditions.  The expression profiles showed different expression patterns with the use of different promoters.  The codon-optimized ThIPK2 gene is a candidate gene to enhance wheat drought stress tolerance by genetic engineering.
     
    Reference | Related Articles | Metrics
    Bioinformatic identification and analyses of the non-specific lipid transfer proteins in wheat
    FANG Zheng-wu, HE Yi-qin, LIU Yi-ke, JIANG Wen-qiang, SONG Jing-han, WANG Shu-ping, MA Dong-fang, YIN Jun-liang
    2020, 19 (5): 1170-1185.   DOI: 10.1016/S2095-3119(19)62776-0
    Abstract110)      PDF in ScienceDirect      
    Non-specific lipid transfer proteins (nsLTPs/LTPs) that can transport various phospholipids across the membrane in vitro are widespread in the plant kingdom, and they play important roles in many biological processes that are closely related to plant growth and development.  Recently, nsLTPs have been shown to respond to different forms of abiotic stresses.  Despite the vital roles of nsLTPs in many plants, little is known about the nsLTPs in wheat.  In this study, 330 nsLTP proteins were identified in wheat and they clustered into five types (1, 2, c, d, and g) by phylogenetic analysis with the nsLTPs from maize, Arabidopsis, and rice.  The wheat nsLTPs of type d included three subtypes (d1, d2, and d3) and type g included seven subtypes (g1–g7).  Genetic structure and motif pattern analyses showed that members of each type had similar structural composition.  Moreover, GPI-anchors were found to exist in non-g type members from wheat for the first time.  Chromosome mapping revealed that all five types were unevenly and unequally distributed on 21 chromosomes.  Furthermore, gene duplication events contributed to the proliferation of the nsLTP genes.  Large-scale data mining of RNA-seq data covering multiple growth stages and numerous stress treatments showed that the transcript levels of some of the nsLTP genes could be strongly induced by abiotic stresses, including drought and salinity, indicating their potential roles in mediating the responses of the wheat plants to these abiotic stress conditions.  These findings provide comprehensive insights into the nsLTP family members in wheat, and offer candidate nsLTP genes for further studies on their roles in stress resistance and potential for improving wheat breeding programs.
     
    Reference | Related Articles | Metrics
    dCAPS markers developed for nitrate transporter genes TaNRT2L12s associating with 1 000-grain weight in wheat
    HUANG Jun-fang, LI Long, MAO Xin-guo, WANG Jing-yi, LIU Hui-min, LI Chao-nan, JING Rui-lian
    2020, 19 (6): 1543-1553.   DOI: 10.1016/S2095-3119(19)62683-3
    Abstract92)      PDF in ScienceDirect      
    Nitrate transporters (NRTs) are regulators of nitrate assimilation and transport.  The genome sequences of TaNRT2L12-A, -B and -D were cloned from wheat (Triticum aestivum L.), and polymorphisms were analyzed by sequencing.  TaNRT2L12-D in a germplasm population was highly conserved.  However, 38 single nucleotide polymorphisms (SNPs) in TaNRT2L12-A coding region and 11 SNPs in TaNRT2L12-B coding region were detected.  Two derived cleaved amplified polymorphic sequences (dCAPS) markers A-CSNP1 and A-CSNP2 were developed for TaNRT2L12-A based on SNP-351 and SNP-729, and three haplotypes were identified in the germplasm population.  B-CSNP1 and B-CSNP2 were developed for TaNRT2L12-B based on SNP-237 and SNP-1 227, and three haplotypes were detected in the germplasm population.  Association analyses between the markers and agronomic traits in 30 environments and phenotypic comparisons revealed that A-CSNP2-A is a superior allele of shorter plant height (PH), length of penultimate internode (LPI) and peduncle length (PL), B-CSNP2-G is a superior allele of higher grain number per spike (GNS).  Hap-6B-1 containing both superior alleles B-CSNP1-C and B-CSNP2-A is a superior haplotype of 1 000-grain weight (TGW).  Expression analysis showed that TaNRT2L12-B is mainly expressed in the root base and regulated by nitrate.  Therefore, TaNRT2L12 may be involved in nitrate transport and signaling to regulate TGW in wheat.  The superior alleles and dCAPS markers of TaNRT2L12-A/B are beneficial to genetic improvement and germplasm enhancement with molecular markers-assisted selection. 
     
    Reference | Related Articles | Metrics
    Genome-wide identification and transcriptome profiling reveal great expansion of SWEET gene family and their wide-spread responses to abiotic stress in wheat (Triticum aestivum L.)
    QIN Jin-xia, JIANG Yu-jie, LU Yun-ze, ZHAO Peng, WU Bing-jin, LI Hong-xia, WANG Yu, XU Sheng-bao, SUN Qi-xin, LIU Zhen-shan
    2020, 19 (7): 1704-1720.   DOI: 10.1016/S2095-3119(19)62761-9
    Abstract144)      PDF in ScienceDirect      
    The Sugars Will Eventually be Exported Transporter (SWEET) gene family, identified as sugar transporters, has been demonstrated to play key roles in phloem loading, grain filling, pollen nutrition, and plant-pathogen interactions.  To date, the study of SWEET genes in response to abiotic stress is very limited.  In this study, we performed a genome-wide identification of the SWEET gene family in wheat and examined their expression profiles under mutiple abiotic stresses.  We identified a total of 105 wheat SWEET genes, and phylogenic analysis revealed that they fall into five clades, with clade V specific to wheat and its closely related species.  Of the 105 wheat SWEET genes, 59% exhibited significant expression changes after stress treatments, including drought, heat, heat combined with drought, and salt stresses, and more up-regulated genes were found in response to drought and salt stresses.  Further hierarchical clustering analysis revealed that SWEET genes exhibited differential expression patterns in response to different stress treatments or in different wheat cultivars.  Moreover, different phylogenetic clades also showed distinct response to abiotic stress treatments.  Finally, we found that homoeologous SWEET genes from different wheat subgenomes exhibited differential expression patterns in response to different abiotic stress treatments.  The genome-wide analysis revealed the great expansion of SWEET gene family in wheat and their wide participation in abiotic stress response.  The expression partitioning of SWEET homoeologs under abiotic stress conditions may confer greater flexibility for hexaploid wheat to adapt to ever changing environments.
    Reference | Related Articles | Metrics
    Genetic analysis and QTL mapping of a novel reduced height gene in common wheat (Triticum aestivum L.)
    ZHOU Chun-yun, XIONG Hong-chun, LI Yu-ting, GUO Hui-jun, XIE Yong-dun, ZHAO Lin-shu, GU Jiayu, ZHAO Shi-rong, DING Yu-ping, SONG Xi-yun, LIU Lu-xiang
    2020, 19 (7): 1721-1730.   DOI: 10.1016/S2095-3119(20)63224-5
    Abstract147)      PDF in ScienceDirect      
    Low stature in wheat is closely associated with lodging resistance, and this impacts harvest index and grain yield.  The discovery of novel dwarfing or semi-dwarfing genes can have great significance for dwarf wheat breeding.  In this study, we identified an EMS-induced dwarf wheat mutant JE0124 from the elite cultivar Jing411.  JE0124 possesses increased stem strength and a 33% reduction in plant height compared with wild type.  Gibberellic acid (GA) treatment analysis suggested that JE0124 was GA-sensitive.  Analysis of the frequency distribution of plant height in four F2 populations derived from crosses between JE0124 and the relatively taller varieties Nongda 5181 and WT indicated that the dwarfism phenotype was quantitatively inherited.  We used two F2 populations and 312 individuals from the reciprocal cross of Nongda 5181 and JE0124 to map the quantitative trait locus (QTL) for reduced height to a 0.85-cM interval on chromosome 2DL.  The mapping was done by using a combination of 660K SNP array-based bulked segregant analysis (BSA) and genetic linkage analysis, with logarithm of odds (LOD) scores of 5.34 and 5.78, respectively.  Additionally, this QTL accounted for 8.27–8.52% of the variation in the phenotype.  The dwarf mutant JE0124 and the newly discovered dwarfing gene on chromosome 2DL in this study will enrich genetic resources for dwarf wheat breeding.
     
    Reference | Related Articles | Metrics
    Quantitative trait loci analysis for root traits in synthetic hexaploid wheat under drought stress conditions
    LIU Rui-xuan, WU Fang-kun, YI Xin, LIN Yu, WANG Zhi-qiang, LIU Shi-hang, DENG Mei, MA Jian, WEI Yu-ming, ZHENG You-liang, LIU Ya-xi
    2020, 19 (8): 1947-1960.   DOI: 10.1016/S2095-3119(19)62825-X
    Abstract143)      PDF in ScienceDirect      
    Synthetic hexaploid wheat (SHW), possesses numerous genes for drought that can help breeding for drought-tolerant wheat varieties.  We evaluated 10 root traits at seedling stage in 111 F9 recombinant inbred lines derived from a F2 population of a SHW line (SHW-L1) and a common wheat line, under normal (NC) and polyethylene glycol-simulated drought stress conditions (DC).  We mapped quantitative trait loci (QTLs) for root traits using an enriched high-density genetic map containing 120 370 single nucleotide polymorphisms (SNPs), 733 diversity arrays technology markers (DArT) and 119 simple sequence repeats (SSRs).  With four replicates per treatment, we identified 19 QTLs for root traits under NC and DC, and 12 of them could be consistently detected with three or four replicates.  Two novel QTLs for root fresh weight and root diameter under NC explained 9 and 15.7% of the phenotypic variation respectively, and six novel QTLs for root fresh weight, the ratio of root water loss, total root surface area, number of root tips, and number of root forks under DC explained 8.5–14% of the phenotypic variation.  Here seven of eight novel QTLs could be consistently detected with more than three replicates.  Results provide essential information for fine-mapping QTLs related to drought tolerance that will facilitate breeding drought-tolerant wheat cultivars.
    Reference | Related Articles | Metrics
    The wheat receptor-like cytoplasmic kinase TaRLCK1B is required for host immune response to the necrotrophic pathogen Rhizoctonia cerealis
    WU Tian-ci, ZHU Xiu-liang, LÜ Liang-jie, CHEN Xi-yong, XU Gang-biao, ZHANG Zeng-yan
    2020, 19 (11): 2616-2627.   DOI: 10.1016/S2095-3119(20)63160-4
    Abstract102)      PDF in ScienceDirect      
    Receptor-like cytoplasmic kinases (RLCKs) represent a large family of proteins in plants.  In Arabidopsis and rice, several RLCKs in subfamily VII (RLCKs-VII) have been implicated in pathogen-associated molecular pattern-triggered immunity and basal resistance against bacterial and fungal pathogens.  However, little is known about roles of RLCKs-VII of the important crop common wheat (Triticum aestivum) in immune responses.  Here, we isolated a RLCK-VII-encoding gene from wheat, designated as TaRLCK1B, and investigated its role in host immune response to infection of a necrotrophic fungus Rhizoctonia cerealis that is a major pathogen of sharp eyespot, a destructive disease of wheat.  RNA-sequencing and RT-qPCR analyses showed that transcriptional level of TaRLCK1B was significantly higher in sharp eyespot-resistant wheat cultivars than in susceptible wheat cultivars.  The gene transcription was rapidly and markedly elevated in the resistant wheat cultivars by R. cerealis infection.  The TaRLCK1B protein was closely related to OsRLCK176, a rice resistance-related RLCKs-VII, with 84.03% identity.  Virus-induced gene silencing plus wheat response to R. cerealis assay results indicated that silencing of TaRLCK1 impaired resistance to R. cerealis.  Meantime, silencing of TaRLCK1 significantly elevated both the content of H2O2 (a major kind of reactive oxygen species, ROS) and the transcriptional level of the ROS-generating enzyme-encoding gene RBOH, but repressed the expression of the ROS-scavenging enzyme-encoding gene CAT1 at 18 hours after inoculation (hai) with R. cerealis.  Taken together, these data suggested that TaRLCK1B was required for the early immune response of wheat to R. cerealis through modulating ROS signaling in wheat.
    Reference | Related Articles | Metrics
    Grain proteomic analysis reveals central stress responsive proteins caused by wheat-Haynaldia villosa 6VS/6AL translocation
    ZOU Rong, WU Ji-su, WANG Ruo-mei, YAN Yue-ming
    2020, 19 (11): 2628-2642.   DOI: 10.1016/S2095-3119(19)62846-7
    Abstract84)      PDF in ScienceDirect      
    Haynaldia villosa (2n=14, VV), a wild grass of the subtribe Triticeae, serves as potential gene resources for wheat genetic improvement.  In this study, the proteome characterization during grain development of Yangmai 5 and Yangmai 5-H. villosa 6VS/6AL translocation line was investigated by a comparative proteomic approach.  Two-dimensional electrophoresis identified 81 differentially accumulated proteins (DAPs) during five grain developmental stages in wheat-H. villosa translocation line.  These proteins were mainly involved in stress defense, storage protein, energy metabolism, protein metabolism and folding, carbon metabolism, nitrogen metabolism, and starch metabolism.  In particular, 6VS/6AL translocation led to significant upregulation of 36 DAPs and specific expression of 11 DAPs such as chitinase, thaumatin-like proteins, glutathione transferase, α-amylase inhibitor, heat shock proteins, and betaine aldehyde dehydrogenase.  These proteins mainly involved in biotic and abiotic stress responses.  Further analysis found that the upstream 1 500 promoter regions of these stress-responsive DAP genes contained multiple high-frequency cis-acting elements related to stress defense such as abscisic acid response element ABRE, methyl jasmonate (MeJA)-response element TGACG-motif and CGTCA-motif involved in oxidative stress and antioxidant response element (ARE).  RNA-seq and RT-qPCR analyses revealed the high expression of these stress-defensive DAP genes in the developing grains, particularly at the early-middle grain filling stages.  Our results demonstrated that 6VS chromosome of H. villosa contains abundant stress-defensive proteins that have potential values for wheat genetic improvement.
    Reference | Related Articles | Metrics
    TaSnRK2.4 is a vital regulator in control of thousand-kernel weight and response to abiotic stress in wheat
    MIAO Li-li, LI Yu-ying, ZHANG Hong-juan, ZHANG Hong-ji, LIU Xiu-lin, WANG Jing-yi, CHANG Xiao-ping, MAO Xin-guo, JING Rui-lian
    2021, 20 (1): 46-54.   DOI: 10.1016/S2095-3119(19)62830-3
    Abstract116)      PDF in ScienceDirect      
    Sucrose non-fermenting 1-related protein kinase 2 (SnRK2) is a plant-specific serine/threonine kinase involved in response to adverse environmental stimuli.  Previous studies showed that TaSnRK2.4 was involved in response to abiotic stresses and conferred enhanced tolerance to multiple stresses in Arabidopsis.  Further experiments were performed to decipher the underlying mechanisms and discover new functions.  The genomic sequences of TaSnRK2.4s locating on chromosome 3A, 3B and 3D were obtained.  Sequencing identified one and 13 variations of TaSnRK2.4-3A and TaSnRK2.4-3B, respectively, but no variation was detected in TaSnRK2.4-3D.  The markers 2.4AM1, 2.4BM1 and 2.4BM2 were developed based on three variations.  Association analysis showed that both TaSnRK2.4-3A and TaSnRK2.4-3B were significantly associated with thousand-kernel weight (TKW), and that SNP3A-T and SNP3B-C were favorable alleles for higher TKW.  Yeast two-hybrid and split luciferase assays showed that TaSnRK2.4 physically interacted with abiotic stress responsive protein TaLTP3, suggesting that TaSnRK2.4 enhanced abiotic stress tolerance by activating TaLTP3.  Our studies suggested that TaSnRK2.4 have potential in improving TKW and response to abiotic stress.
     
    Reference | Related Articles | Metrics
    QTL mapping of seedling biomass and root traits under different nitrogen conditions in bread wheat (Triticum aestivum L.)
    YANG Meng-jiao, WANG Cai-rong, Muhammad Adeel HASSAN, WU Yu-ying, XIA Xian-chun, SHI Shu-bing, XIAO Yong-gui, HE Zhong-hu
    2021, 20 (5): 1180-1192.   DOI: 10.1016/S2095-3119(20)63192-6
    Abstract130)      PDF in ScienceDirect      
    Plant nitrogen assimilation and use efficiency in the seedling’s root system are beneficial for adult plants in field condition for yield enhancement.  Identification of the genetic basis between root traits and N uptake plays a crucial role in wheat breeding.  In the present study, 198 doubled haploid lines from the cross of Yangmai 16/Zhongmai 895 were used to identify quantitative trait loci (QTLs) underpinning four seedling biomass traits and five root system architecture (RSA) related traits.  The plants were grown under hydroponic conditions with control, low and high N treatments (Ca(NO3)2·4H2O at 0, 0.05 and 2.0 mmol L−1, respectively).  Significant variations among the treatments and genotypes, and positive correlations between seedling biomass and RSA traits (r=0.20 to 0.98) were observed.  Inclusive composite interval mapping based on a high-density map from the Wheat 660K single nucleotide polymorphisms (SNP) array identified 51 QTLs from the three N treatments.  Twelve new QTLs detected on chromosomes 1AL (1) in the control, 1DS (2) in high N treatment, 4BL (5) in low and high N treatments, and 7DS (3) and 7DL (1) in low N treatments, are first reported in influencing the root and biomass related traits for N uptake.  The most stable QTLs (RRS.caas-4DS) on chromosome 4DS, which were related to ratio of root to shoot dry weight trait, was in close proximity of the Rht-D1 gene, and it showed high phenotypic effects, explaining 13.1% of the phenotypic variance.  Twenty-eight QTLs were clustered in 12 genetic regions.  SNP markers tightly linked to two important QTLs clusters C10 and C11 on chromosomes 6BL and 7BL were converted to kompetitive allele-specific PCR (KASP) assays that underpin important traits in root development, including root dry weight, root surface area and shoot dry weight.  These QTLs, clusters and KASP assays can greatly improve the efficiency of selection for root traits in wheat breeding programmes.
     
    Reference | Related Articles | Metrics
    Heredity and gene mapping of a novel white stripe leaf mutant in wheat
    LI Hui-juan, JIAO Zhi-xin, NI Yong-jing, JIANG Yu-mei, LI Jun-chang, PAN Chao, ZHANG Jing, SUN Yu-long, AN Jun-hang, LIU Hong-jie, LI Qiao-yun, NIU Ji-shan
    2021, 20 (7): 1743-1752.   DOI: 10.1016/S2095-3119(20)63345-7
    Abstract82)      PDF in ScienceDirect      
    Spotted leaf (spl) mutant is a type of leaf lesion mimic mutants in plants.  We obtained some lesion mimic mutants from ethyl methane sulfonate (EMS)-mutagenized wheat (Triticum aestivum L.) cultivar Guomai 301 (wild type, WT), and one of them was named as white stripe leaf (wsl) mutant because of the white stripes on its leaves.  Here we report the heredity and gene mapping of this novel wheat mutant wsl.  There are many small scattered white stripes on the leaves of wsl throughout its whole growth period.  As the plants grew, the white stripes became more severe and the necrotic area expanded.  The mutant wsl grew only weakly before the jointing stage and gradually recovered after jointing.  The length and width of the flag leaf, spike number per plant and thousand-grain weight of wsl were significantly lower than those of the WT.  Genetic analysis indicated that the trait of white stripe leaf was controlled by a recessive gene locus, named as wsl, which was mapped on the short arm of chromosome 6B by SSR marker assay.  Four SSR markers in the F2 population of wsl×CS were linked to wsl in the order of Xgpw1079Xwmc104Xgwm508-wslXgpw7651 at 7.1, 5.2, 8.7, and 4.4 cM, respectively and three SSR markers in the F2 population of wsl×Jimai 22 were linked to wsl in the order of Xgwm508Xwmc494Xgwm518-wsl at 3.5, 1.6 and 8.2 cM, respectively.  In comparison to the reference genome sequence of Chinese Spring (CS), wsl is located in a 91-Mb region from 88 Mb (Xgwm518) to 179 Mb (Xgpw7651) on chromosome 6BS.  Mutant wsl is a novel germplasm for studying the molecular mechanism of wheat leaf development.
    Reference | Related Articles | Metrics
    Physiological response of flag leaf and yield formation of winter wheat under different spring restrictive irrigation regimes in the Haihe Plain, China
    LIU Xue-jing, YIN Bao-zhong, HU Zhao-hui, BAO Xiao-yuan, WANG Yan-dong, ZHEN Wen-chao
    2021, 20 (9): 2343-2359.   DOI: 10.1016/S2095-3119(20)63352-4
    Abstract99)      PDF in ScienceDirect      
    In order to identify the optimum period of spring water-restrictive irrigation for winter wheat (Triticum aestivum L.) in the Haihe Plain, China and elucidate its effects on flag leaf senescence and yield formation, field experiments were conducted at the Xinji Experimental Station of Hebei Agricultural University from 2016 to 2019 by using different irrigation regimes in spring, including the conventional regime involving two irrigation periods (control (CK), the 3-leaf unfolding stage and the anthesis stage) and a series of single, restrictive irrigation regimes (SRI) comprising irrigation at the 3-leaf unfolding stage (3LI), 4LI, 5LI, and 6LI.  There are five major findings: (1) The senescence (determined by the green leaf area, GLA) in the 4LI treatment occurred moderately earlier than that in CK, showed no significant difference with that in 5LI and 6LI, and occurred significantly later than that in 3LI.  (2) Compared with other SRI treatments, the GLA value and photosynthetic rate in 4LI were 14.82 and 20.1% higher, respectively.  Microstructural analysis of flag leaf also revealed that the mesophyll cells and chloroplasts were irregularly arranged under drought stress in 3LI and 6LI; however, drought stress had minimal negative effects on the microstructure in 4LI and 5LI.  (3) Postponed irrigation in spring could significantly increase superoxide dismutase (SOD) and catalase (CAT) activities in the early stage of grain filling; however, these activities would subsequently decrease.  Among the four SRI treatments, the overall enzyme activities were the highest in 4LI, and the combined malondialdehyde (MDA) content in flag leaves in 4LI and 5LI was 14.5% lower on average than that in 3LI and 6LI.  (4) The soluble sugar (SS) and proline (Pro) contents in 4LI were the highest among the four SRI treatments; however, they were lower than those in CK.  The abscisic acid (ABA) hormone content in 4LI and 5LI was lower than that in 3LI and 6LI, respectively, suggesting a smaller drought stress effect in 4LI and 5LI.  (5) In two growing seasons, there was a larger number of spikes per unit area in 4LI (i.e., 13.4% higher than that in 5LI and 6LI) and the 1 000-grain weight in 4LI was the highest among the four SRI treatments (i.e., 6.0% higher than that in the other three SRI treatments).  Therefore, a single restrictive irrigation regime at the 4-leaf unfolding stage is recommended to be effective in slowing down the senescence process of flag leaves and achieving high yield.
     
    Reference | Related Articles | Metrics
    Genetic dissection of wheat uppermost-internode diameter and its association with agronomic traits in five recombinant inbred line populations at various field environments
    LIU Hang, TANG Hua-ping, LUO Wei, MU Yang, JIANG Qian-tao, LIU Ya-xi, CHEN Guo-yue, WANG Ji-rui, ZHENG Zhi, QI Peng-fei, JIANG Yun-feng, CUI Fa, SONG Yin-ming, YAN Gui-jun, WEI Yuming, LAN Xiu-jin, ZHENG You-liang, MA Jian
    2021, 20 (11): 2849-2861.   DOI: 10.1016/S2095-3119(20)63412-8
    Abstract148)      PDF in ScienceDirect      
    Uppermost-internode diameter (UID) is a key morphological trait associated with spike development and yield potential in wheat.  Our understanding of its genetic basis remains largely unknown.  Here, quantitative trait loci (QTLs) for UID with high-density genetic maps were identified in five wheat recombinant inbred line (RIL) populations.  In total, 25 QTLs for UID were detected in five RIL populations, and they were located on chromosomes 1A, 1D (3 QTL), 2B (2), 2D (3), 3B, 3D, 4A, 4B (3), 4D, 5A (5), 5B (2), 6B, and 7D.  Of them, five major and stable QTLs (QUid.sau-2CN-1D.1, QUid.sau-2SY-1D, QUid.sau-QZ-2D, QUid.sau-SC-3D, and QUid.sau-AS-4B) were identified from each of the five RIL populations in multiple environments.  QUid.sau-2CN-1D.1, QUid.sau-2SY-1D and QUid.sau-SC-3D are novel QTLs.  Kompetitive Allele Specific PCR (KASP) markers tightly linked to them were further investigated for developing near-isogenic lines (NILs) carrying the major loci.  Furthermore, candidate genes at these intervals harboring major and stable QTLs were predicted, and they were associated with plant development and water transportation in most cases.  Comparison of physical locations of the identified QTL on the ‘Chinese Spring’ reference genome showed that several QTLs including two major ones, QUid.sau-2CN-1D.1 and QUid.sau-2SY-1D, are likely allelic confirming their validity and effectiveness.  The significant relationships detected between UID and other agronomic traits and a proper UID were discussed.  Collectively, our results dissected the underlying genetic basis for UID in wheat and laid a foundation for further fine mapping and map-based cloning of these QTLs.
    Reference | Related Articles | Metrics
    Identification of genetic locus with resistance to take-all in the wheat-Psathyrostachys huashanica Keng introgression line H148
    BAI Sheng-sheng, ZHANG Han-bing, HAN Jing, WU Jian-hui, LI Jia-chuang, GENG Xing-xia, LÜ Bo-ya, XIE Song-feng, HAN De-jun, ZHAO Ji-xin, YANG Qun-hui, WU Jun, CHEN Xin-hong
    2021, 20 (12): 3101-3113.   DOI: 10.1016/S2095-3119(20)63340-8
    Abstract211)      PDF in ScienceDirect      
    Take-all is a devastating soil-borne disease of wheat (Triticum aestivum L.).  Cultivating resistant line is an important measure to control this disease.  Psathyrostachys huashanica Keng is a valuable germplasm resource with high resistance to take-all.  This study reported on a wheat-P. huashanica introgression line H148 with improved take-all resistance compared with its susceptible parent 7182.  To elucidate the genetic mechanism of resistance in H148, the F2 genetic segregating population of H148×XN585 was constructed.  The mixed genetic model analysis showed that the take-all resistance was controlled by two major genes with additive, dominant and epistasis effects.  Bulked segregant analysis combined with wheat axiom 660K genotyping array analysis showed the polymorphic SNPs with take-all resistance from P. huashanica alien introgression were mainly distributed on the chromosome 2A.  Genotyping of the F2 population using the KASP marker mapped a major QTL in an interval of 68.8–70.1 Mb on 2AS.  Sixty-two genes were found in the target interval of the Chinese Spring reference genome sequence.  According to the functional annotation of genes, two protein genes that can improve the systematic resistance of plant roots were predicted as candidate genes.  The development of wheat-P. huashanica introgression line H148 and the resistant QTL mapping information are expected to provide some valuable references for the fine mapping of disease-resistance gene and development of take-all resistant varieties through molecular marker-assisted selection.
    Reference | Related Articles | Metrics
    Analysis of combining ability for stem-related traits and its correlations with lodging resistance heterosis in hybrid wheat
    YANG Wei-bing, QIN Zhi-lie, SUN Hui, HOU Qi-ling, GAO Jian-gang, CHEN Xian-chao, ZHANG Li-ping, WANG Yong-bo, ZHAO Chang-ping, ZHANG Feng-ting
    2022, 21 (1): 26-35.   DOI: 10.1016/S2095-3119(20)63408-6
    Abstract182)      PDF in ScienceDirect      
    With the application of hybrid wheat, lodging is becoming one of the major factors limiting high yield in its production.  However, few studies have focused on combining ability and heterosis analysis of stem-related traits.  In this study, 24 crosses were made according to NCII genetic design, using the three (photo-sensitive male sterile lines)×eight (restorer lines) incomplete diallel crosses.  The length of basal second internode (LBSI) and breaking strength of basal second internode (BSBSI) as well as other stem-related traits were used to perform the principal component analysis (PCA), combining ability and heterosis analysis.  The PCA results showed that the variables could be classified into two main factors, which were named as the positive factor (factor 1) and the negative factor (factor 2), and accounted for 52.3 and 33.2%, respectively, of the total variance in different variables, combined with the analysis for index weight indicated that the factor 1-related traits play positive roles in lodging resistance formation of hybrids.  Combining ability variance analysis indicated that its genetic performance was mainly dominated by additive gene effects, and the hybrid combinations with higher lodging resistance can be selected by using of 14GF6085 (R1), 14GF6343-2 (R4), 14GF6937 (R6), 14GF7433-1 (R7), and BS1086 (M3), which are with the features with lower general combining ability (GCA) effects of factor 2-related traits whereas higher GCA effects of factor 1-related traits.  The heterosis analysis showed that the wide range of heterosis varied with the traits and combinations, and GCA or specific combining ability (SCA) effects of factor 1-related traits except wall thickness of basal second internode (WTBSI) were positively and closely related to the heterosis of lodging resistance.  Generally, the correlation coefficients of heterosis to GCA effects of sterile lines (GCAm) of factor 1-related traits are significantly higher than that to GCA of restorer lines (GCAr) and SCA, combined with the higher GCAm variance values of factor 1-related traits compared to GCAr, the GCAm of factor 1-related traits should be particularly considered when breeding hybrid combinations.  The heritability analysis showed that the narrow-sense heritability of the diameter of basal second internode (DBSI) and the center of gravity height (TCGH) were obviously lower (<60%) than other traits, suggesting that these two traits were suitable for selection in higher generation for parental breeding.  These could provide a theoretical basis for parental breeding and heterosis utilization of lodging resistance. 

    Reference | Related Articles | Metrics