scholarly journals Current Progress in Understanding and Recovering the Wheat Genes Lost in Evolution and Domestication

2020 ◽  
Vol 21 (16) ◽  
pp. 5836 ◽  
Author(s):  
Shanjida Rahman ◽  
Shahidul Islam ◽  
Zitong Yu ◽  
Maoyun She ◽  
Eviatar Nevo ◽  
...  
Keyword(s):  
Genetic Resource ◽  
Gene Loss ◽  
Evolutionary Process ◽  
Triticum Dicoccoides ◽  
Wheat Breeding ◽  
Biotic And Abiotic Stress ◽  
Wild Progenitor ◽  
Wheat Improvement ◽  
Modern Wheat ◽  
High Level

The modern cultivated wheat has passed a long evolution involving origin of wild emmer (WEM), development of cultivated emmer, formation of spelt wheat and finally establishment of modern bread wheat and durum wheat. During this evolutionary process, rapid alterations and sporadic changes in wheat genome took place, due to hybridization, polyploidization, domestication, and mutation. This has resulted in some modifications and a high level of gene loss. As a result, the modern cultivated wheat does not contain all genes of their progenitors. These lost genes are novel for modern wheat improvement. Exploring wild progenitor for genetic variation of important traits is directly beneficial for wheat breeding. WEM wheat (Triticum dicoccoides) is a great genetic resource with huge diversity for traits. Few genes and quantitative trait loci (QTL) for agronomic, quantitative, biotic and abiotic stress-related traits have already been mapped from WEM. This resource can be utilized for modern wheat improvement by integrating identified genes or QTLs through breeding.

scholarly journals Unravelling the hidden inter and intra-varietal diversity of durum wheat commercial varieties used in Portugal

2019 ◽  
Vol 17 (04) ◽  
pp. 386-389
Author(s):  
Miguel Bento ◽  
Sónia Gomes Pereira ◽  
Wanda Viegas ◽  
Manuela Silva
Keyword(s):  
Durum Wheat ◽  
Repetitive Sequences ◽  
Inter Simple Sequence Repeat ◽  
Wheat Breeding ◽  
Genomic Diversity ◽  
Varietal Diversity ◽  
Wheat Varieties ◽  
Coding Sequences ◽  
Coding Regions ◽  
High Level

AbstractAssessing durum wheat genomic diversity is crucial in a changing environmental particularly in the Mediterranean region where it is largely used to produce pasta. Durum wheat varieties cultivated in Portugal and previously assessed regarding thermotolerance ability were screened for the variability of coding sequences associated with technological traits and repetitive sequences. As expected, reduced variability was observed regarding low molecular weight glutenin subunits (LMW-GS) but a specific LMW-GS allelic form associated with improved pasta-making characteristics was absent in one variety. Contrastingly, molecular markers targeting repetitive elements like microsatellites and retrotransposons – Inter Simple Sequence Repeat (ISSR) and Inter Retrotransposons Amplified Polymorphism (IRAP) – disclosed significant inter and intra-varietal diversity. This high level of polymorphism was revealed by the 20 distinct ISSR/IRAP concatenated profiles observed among the 23 individuals analysed. Interestingly, median joining networks and PCoA analysis grouped individuals of the same variety and clustered varieties accordingly with geographical origin. Globally, this work demonstrates that durum wheat breeding strategies induced selection pressure for some relevant coding sequences while maintaining high levels of genomic variability in non-coding regions enriched in repetitive sequences.

scholarly journals Microevolution within ST11 group Clostridioides difficile isolates through mobile genetic elements based on complete genome sequencing

BMC Genomics ◽  
2019 ◽  
Vol 20 (1) ◽  
Author(s):  
Yuan Wu ◽  
Lin Yang ◽  
Wen-Ge Li ◽  
Wen Zhu Zhang ◽  
Zheng Jie Liu ◽  
...  
Keyword(s):  
Drug Resistance ◽  
Resistance Genes ◽  
Point Mutations ◽  
Evolutionary Process ◽  
Mobile Genetic Elements ◽  
Genetic Elements ◽  
Clostridioides Difficile ◽  
Hospitalized Elderly ◽  
Great Heterogeneity ◽  
High Level

Abstract Background Clade 5 Clostridioides difficile diverges significantly from the other clades and is therefore, attracting increasing attention due its great heterogeneity. In this study, we used third-generation sequencing techniques to sequence the complete whole genomes of three ST11 C. difficile isolates, RT078 and another two new ribotypes (RTs), obtained from three independent hospitalized elderly patients undergoing antibiotics treatment. Mobile genetic elements (MGEs), antibiotic-resistance, drug resistance genes, and virulent-related genes were analyzed and compared within these three isolates. Results Isolates 10,010 and 12,038 carried a distinct deletion in tcdA compared with isolate 21,062. Furthermore, all three isolates had identical deletions and point-mutations in tcdC, which was once thought to be a unique characteristic of RT078. Isolate 21,062 (RT078) had a unique plasmid, different numbers of transposons and genetic organization, and harboring special CRISPR spacers. All three isolates retained high-level sensitivity to 11 drugs and isolate 21,062 (RT078) carried distinct drug-resistance genes and loss of numerous flagellum-related genes. Conclusions We concluded that capillary electrophoresis based PCR-ribotyping is important for confirming RT078. Furthermore, RT078 isolates displayed specific MGEs, indicating an independent evolutionary process. In the further study, we could testify these findings with more RT078 isolates of divergent origins.

scholarly journals Triticum dicoccoides: An important genetic resource for increasing zinc and iron concentration in modern cultivated wheat

2004 ◽  
Vol 50 (7) ◽  
pp. 1047-1054 ◽  
Author(s):  
I. Cakmak ◽  
A. Torun ◽  
E. Millet ◽  
M. Feldman ◽  
T. Fahima ◽  
...  
Keyword(s):  
Genetic Resource ◽  
Iron Concentration ◽  
Triticum Dicoccoides

scholarly journals Alien chromatin but not Fhb7 confers Fusarium head blight resistance in wheat breeding

2021 ◽  
Author(s):  
Xianrui Guo ◽  
Qinghua Shi ◽  
Jing Yuan ◽  
Mian Wang ◽  
Jing Wang ◽  
...  
Keyword(s):  
Fusarium Head Blight ◽  
Fusarium Head Blight Resistance ◽  
Resistance Breeding ◽  
Wheat Breeding ◽  
Glutathione S Transferase ◽  
Head Blight ◽  
Fhb Resistance ◽  
Translocation Lines ◽  
High Level ◽  
Thinopyrum Elongatum

AbstractFusarium head blight (FHB), caused by Fusarium species, seriously threaten global wheat production. Three wheat-Th.elongatum FHB resistant translocation lines have been developed and used for breeding. Transcriptomic analysis identified a derivative glutathione S-transferase transcript T26102, which was homologous to Fhb7 and induced dramatically by Fusarium graminearum. Homologs of Fhb7 were detected in several genera in Triticeae, including Thinopyrum, Elymus, Leymus, Pseudoroegeria and Roegeria. Several wheat-Thinopyrum translocation lines carrying Fhb7 remain susceptible to FHB, and transgenic plants overexpressing the T26102 on different backgrounds did not improve the FHB resistance. Taken as a whole, we show the application of the chromatin derived from diploid Thinopyrum elongatum successfully conferring wheat with high level FHB resistance independent of the Fhb7.One Sentence SummaryThinopyrum elongatum chromatin from 7EL was successfully applied to wheat FHB resistance breeding, but the resistant gene other than the reported Fhb7 remained unknown.

scholarly journals A Survey on Detection, Tracking and Identification in Radio Frequency-Based Device-Free Localization

Sensors ◽  
2019 ◽  
Vol 19 (23) ◽  
pp. 5329 ◽  
Author(s):  
Stijn Denis ◽  
Rafael Berkvens ◽  
Maarten Weyn
Keyword(s):  
Evolutionary Process ◽  
Identification Problem ◽  
Channel State ◽  
Comprehensive Overview ◽  
Research Directions ◽  
High Level ◽  
Active Localization ◽  
Key Techniques ◽  
Device Free ◽  
Current Blocking

The requirement of active localization techniques to attach a hardware device to the targets that need to be located can be difficult or even impossible for certain applications. For this reason, there has been an increasing interest in tagless or device-free localization (DFL) approaches. In particular, the research domain of RF-based device-free localization has been steadily evolving since its inception slightly over a decade ago. Many novel techniques have been developed regarding the three core aspects of DFL: detection, tracking, and identification. The increasing use of channel state information (CSI) has contributed considerably to these developments. In particular, the progress it enabled regarding the exceptionally difficult `identification problem’ has been highly impressive. In this survey, we provide a comprehensive overview of this evolutionary process, describe essential DFL concepts and highlight several key techniques whose creation marked important milestones within this field of research. We do so in a structured manner in which each technique is categorized according to the DFL core aspect it emphasizes most. Additionally, we discuss current blocking issues within the state-of-the-art and suggest multiple high-level research directions which will aid in the search towards eventual solutions.

scholarly journals Advances in Wheat and Pathogen Genomics: Implications for Disease Control

2018 ◽  
Vol 56 (1) ◽  
pp. 67-87 ◽  
Author(s):  
Beat Keller ◽  
Thomas Wicker ◽  
Simon G. Krattinger
Keyword(s):  
Disease Resistance ◽  
Molecular Level ◽  
Resistance Breeding ◽  
Wheat Breeding ◽  
The Past ◽  
Wheat Improvement ◽  
Disease Resistance Breeding ◽  
Near Future ◽  
New Cultivars ◽  
Made In

The gene pool of wheat and its wild and domesticated relatives contains a plethora of resistance genes that can be exploited to make wheat more resilient to pathogens. Only a few of these genes have been isolated and studied at the molecular level. In recent years, we have seen a shift from classical breeding to genomics-assisted breeding, which makes use of the enormous advancements in DNA sequencing and high-throughput molecular marker technologies for wheat improvement. These genomic advancements have the potential to transform wheat breeding in the near future and to significantly increase the speed and precision at which new cultivars can be bred. This review highlights the genomic improvements that have been made in wheat and its pathogens over the past years and discusses their implications for disease-resistance breeding.

scholarly journals Effect of gibberellin-sensitive Rht18 and gibberellin-insensitive Rht-D1b dwarfing genes on vegetative and reproductive growth in bread wheat

2020 ◽  
Author(s):  
Ting Tang ◽  
Tina Botwright Acuña ◽  
Wolfgang Spielmeyer ◽  
Richard A Richards
Keyword(s):  
Dry Matter ◽  
Green Revolution ◽  
Dominant Gene ◽  
Early Growth ◽  
Wheat Breeding ◽  
Dwarfing Genes ◽  
Coleoptile Length ◽  
Backcross Population ◽  
Wheat Improvement ◽  
Vegetative And Reproductive Growth

Abstract Gibberellin (GA)-insensitive dwarfing genes Rht-B1b and Rht-D1b that are responsible for the ‘Green Revolution’ have been remarkably successful in wheat improvement globally. However, these alleles result in shorter coleoptiles and reduced vigour, and hence poor establishment and growth in some environments. Rht18, on the other hand, is a GA-sensitive, dominant gene with potential to overcome some of the early growth limitations associated with Rht-B1b and Rht-D1b. We assessed progeny from both a biparental and a backcross population that contained tall, single dwarf, and double dwarf lines, to determine whether Rht18 differs from Rht-D1b and hence verify its value in wheat improvement. Progeny with Rht18 had an almost identical height to lines with Rht-D1b, and both were ~26% shorter than the tall lines, with the double dwarf 13% shorter again. However, coleoptile length of Rht18 was 42% longer than that of Rht-D1b. We detected no differences in time to terminal spikelet and anthesis, and few differences in stem or spike growth. Both dwarfing genes diverted more dry matter to the spike than tall lines from prior to heading. No differences were detected between Rht18 and Rht-D1b that could prevent the adoption of Rht18 in wheat breeding to overcome some of the limitations associated with the ‘Green Revolution’ genes.

scholarly journals Advances in Genomic Interventions for Wheat Biofortification: A Review

Agronomy ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 62 ◽  
Author(s):  
Dinesh Kumar Saini ◽  
Pooja Devi ◽  
Prashant Kaushik
Keyword(s):  
Qtl Mapping ◽  
Crop Improvement ◽  
Essential Elements ◽  
Wheat Breeding ◽  
Wheat Varieties ◽  
New Horizons ◽  
Hidden Hunger ◽  
Modern Wheat ◽  
Breeding Efficiency ◽  
Molecular Bases

Wheat is an essential constituent of cereal-based diets, and one of the most significant sources of calories. However, modern wheat varieties are low in proteins and minerals. Biofortification is a method for increasing the availability of essential elements in the edible portions of crops through agronomic or genetic and genomic interventions. Wheat biofortification, as a research topic, has become increasingly prevalent. Recent accomplishments in genomic biofortification could potentially be helpful for the development of biofortified wheat grains, as a sustainable solution to the issue of “hidden hunger”. Genomic interventions mainly include quantitative trait loci (QTL) mapping, marker-assisted selection (MAS), and genomic selection (GS). Developments in the identification of QTL and in the understanding of the physiological and molecular bases of the QTLs controlling the biofortification traits in wheat have revealed new horizons for the improvement of modern wheat varieties. Markers linked with the QTLs of desirable traits can be identified through QTL mapping, which can be employed for MAS. Besides MAS, a powerful tool, GS, also has great potential for crop improvement. We have compiled information from QTL mapping studies on wheat, carried out for the identification of the QTLs associated with biofortification traits, and have discussed the present status of MAS and different prospects of GS for wheat biofortification. Accelerated mapping studies, as well as MAS and GS schemes, are expected to improve wheat breeding efficiency further.

scholarly journals 1RS.1BL molecular resolution provides novel contributions to wheat improvement

2020 ◽  
Author(s):  
Zhengang Ru ◽  
Angela Juhasz ◽  
Danping Li ◽  
Pingchuan Deng ◽  
Jing Zhao ◽  
...  
Keyword(s):  
Fertility Restoration ◽  
Wheat Yield ◽  
Biotic And Abiotic Stress ◽  
Protein Coding ◽  
Wheat Improvement ◽  
Gene Alignment ◽  
High Resolution Structure ◽  
Ppr Genes ◽  
Genomic Basis ◽  
Active Centromere

SUMMARYWheat-rye 1RS.1BL translocation has a significant impact on wheat yield and hence food production globally. However, the genomic basis of its contributions to wheat improvement is undetermined. Here, we generated a high-quality assembly of 1RS.1BL translocation comprising 748,715,293 bp with 4,996 predicted protein-coding genes. We found the size of 1RS is larger than 1BS with the active centromere domains shifted to the 1RS side instead of the 1BL side in Aikang58 (AK58). The gene alignment showed excellent synteny with 1BS from wheat and genes from 1RS were expressed well in wheat especially for 1RS where expression was higher than that of 1BS for the grain-20DPA stage associated with greater grain weight and negative flour quality attributes. A formin-like-domain protein FH14 (TraesAK58CH1B01G010700) was important in regulating cell division. Two PPR genes were most likely the genes for the multi fertility restoration locus Rf multi. Our data not only provide the high-resolution structure and gene complement for the 1RS.1BL translocation, but also defined targets for enhancing grain yield, biotic and abiotic stress, and fertility restoration in wheat.

scholarly journals Variation of specific morphological traits and ploidy level of five Aegilops L. species in Morocco.

2003 ◽  
Vol 28 ◽  
pp. 47-58
Author(s):  
Bouchra Belkadi ◽  
Nourredine Assali ◽  
Ouafae Benlhabib
Keyword(s):  
Ploidy Level ◽  
Morphological Traits ◽  
Cytogenetic Study ◽  
Morphological Characters ◽  
Wheat Breeding ◽  
Morphological Data ◽  
Biotic And Abiotic Stress ◽  
Triticum Spp ◽  
Total Variability

ABSTRACT. Variation of specific morphological traits and ploidy level of five Aegilops L. species in Morocco.The genus Aegilops L. represents an important natural source of useful genes for wheat breeding, with particular emphasis on biotic and abiotic stress resistance. For successful crosses, the primarily step is to select appropriate Aegilops accessions. In this paper, we studied five Moroccan species of an Aegilops collection on the basis of spike structure and chromosome number. Twenty-eight specific morphological characters were used to differentiate the species. Statistical analyses, in particular the DFA, allowed the characterization of the genetic variability of the species; the two first standardized axes explained 96,2% of the total variability and 100% of the entities were classified within their own group. In addition, the dendrogram constructed using morphological data reveals a significant variability within and between species. Cytogenetic study revealed four species, A. geniculata Roth, A. triuncialis L., A. ventricosa Tausch and A.peregrina Maire & Weiller, to be tetraploid. However, A. neglecta Req. ex. Bertol., where only two accessions are represented in the collection, revealed to be hexaploid, and can then be classified as A. neglecta subsp. recta Chennav.Key words. Aegilops, Variation, Morphology, Ploidy, Morocco.RÉSUMÉ. Variation des caracteres morphologiques specificities et niveau de plordie de an(' espéces Aegilops L. au Maroc. Le genre Aegilops L. représente une importante source de genes, potentiellement utilisables dans Pamelioration des blés cultivés (Triticum spp.) notamment pour la resistance aux stress biotiques et abiotiques. Le choix des accessions Aegilops á employer, dans un programme d' hybridation interspécifique, necessite une caractérisation taxonomique et une evaluation préalables. L'objectif de ce travail a ete d'étudier des accessions, appartenant á 5 especes marocaines constituant une collection d'Aegilops, sur la base de caracteres morphologiques specifiques de l'épi et du niveau de ploYdie. La caractérisation phénotypique a été basée sur l'étude de 28 caracteres morphologiques qui discriminent entre les especes. Les resultats des analyses statistiques, en particulier de l'AFD, ont permis de caractériser la variabilite génetique de ces especes et ant donne un pourcentage d'appartenance á l'espece de 100%. Aussi, les deux premiers axes standardises expliquent 96,2% de la variabilité totale. Un demlrogramme a éte aussi construit, revelant une variabilite interspecifique. L'étude cytogenétique a révélé une tetraploYdie pour A. geniculata Roth, A. triuncialis L., A. ventricosa Tausch et A. peregrina Maire & Weiller. Quant á A. neglecta Req. ex. Bertol., une hexaploYdie a été mise en evidence pour les deux uniques accessions disponibles dans la collection, permettant de leur attribuer le nom A. neglecta subsp. recta Chennav.Mots clés. Aegilops, Variation, Morphologic, Plolidie, Maroc.

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