Doubled Haploids versus Conventional Breeding in CIMMYT Wheat Breeding Programs

AbstractCommon wheat (Triticum aestivum L.) is one of the three major food crops in the world; thus, wheat breeding programs are important for world food security. Characterizing the genes that control important agronomic traits and finding new ways to alter them are necessary to improve wheat breeding. Functional genomics and breeding in polyploid wheat has been greatly accelerated by the advent of several powerful tools, especially CRISPR/Cas9 genome editing technology, which allows multiplex genome engineering. Here, we describe the development of CRISPR/Cas9, which has revolutionized the field of genome editing. In addition, we emphasize technological breakthroughs (e.g., base editing and prime editing) based on CRISPR/Cas9. We also summarize recent applications and advances in the functional annotation and breeding of wheat, and we introduce the production of CRISPR-edited DNA-free wheat. Combined with other achievements, CRISPR and CRISPR-based genome editing will speed progress in wheat biology and promote sustainable agriculture.

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Revision of the estimates of glutenin gene effects at the Glu-B1 locus from southern Australian wheat breeding programs

Australian Journal of Agricultural Research ◽

10.1071/ar04113 ◽

2004 ◽

Vol 55 (10) ◽

pp. 1093 ◽

Cited By ~ 26

Author(s):

H. A. Eagles ◽

R. F. Eastwood ◽

G. J. Hollamby ◽

E. M. Martin ◽

G. B. Cornish

Keyword(s):

Development Time ◽

Low Frequency ◽

Wheat Breeding ◽

Correct Identification ◽

Gene Effects ◽

Breeding Programs ◽

Multiple Alleles ◽

Intermediate Allele ◽

Dough Extensibility ◽

Dough Development Time

Glutenins are the major determinant of dough characteristics in wheat. These proteins are determined by genes at 6 loci, with multiple alleles present in southern Australian breeding programs. Previously, we estimated the effects of these genes on maximum dough resistance (Rmax), dough extensibility and dough development time. Subsequently, the allele previously classified as Glu-B1b was found to consist of 2 alleles, with one, now considered to be Glu-B1al, producing an overexpression of the Bx7 glutenin subunit. Therefore, there is a potential bias in our previous estimates. An extended dataset was analysed with the 2 alleles now separated. These analyses identified negligible biases in our previous estimates, probably due to a low frequency of Glu-B1al before 1999. However, Glu-B1al produced significantly higher Rmax, dough extensibility, and dough development time values than all other alleles at the Glu-B1 locus. Therefore, at intermediate allele frequencies, substantial bias in estimates of the effects of the Glu-B1 alleles can be expected without correct identification of Glu-B1al.

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Evolution of Physiologic Races and Virulence of Puccinia striiformis on Wheat in Syria and Lebanon

Plant Disease ◽

10.1094/pdis.2002.86.5.499 ◽

2002 ◽

Vol 86 (5) ◽

pp. 499-504 ◽

Cited By ~ 17

Author(s):

A. H. Yahyaoui ◽

M. S. Hakim ◽

M. El Naimi ◽

N. Rbeiz

Keyword(s):

Resistance Genes ◽

Puccinia Striiformis ◽

Yellow Rust ◽

Wheat Breeding ◽

Natural Conditions ◽

Breeding Programs ◽

Land Race ◽

Physiologic Races ◽

Resistant Genotypes

Virulence-avirulence phenotypes of Puccinia striiformis isolates collected in Lebanon and Syria were determined on seedlings of the wheat-yellow rust differential genotypes. We found 25 and 11 physiologic races over 6 years (1994 to 1999) in Syria and Lebanon, respectively. The composition of physiologic races found in Syria and Lebanon differed greatly between 1994 and 1999. Races identified in 1999, such as 230E150 and 230E134, have wider spectra of virulence on resistant genotypes than races collected in 1994. In Lebanon, three races were found in 1994 compared with six races in 1999. Yellow rust differential genotypes were used in a trap nursery to monitor yellow rust populations under natural conditions. Races identified from cultivars in the trap nursery in Syria and Lebanon, and from land race cultivars in Iraq, were recovered among the races identified from farm fields. Yellow rust samples were collected from Yemen, and none of the races identified from Yemen samples were identical to those in Syria and Lebanon. Virulence frequencies in the yellow rust population on the differential genotypes tested in the trap nurseries were above 70% for some resistance genes. Yellow rust populations in Syria and Lebanon have diverse virulence phenotypes. P. striiformis populations appear to be changing over, and this would be an important consideration for wheat breeding programs in the region.

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The limitation of conventional breeding programs and the need and promise of assisted reproduction in nondomestic species

Theriogenology ◽

10.1016/s0093-691x(05)80057-3 ◽

1994 ◽

Vol 41 (1) ◽

pp. 119-132 ◽

Cited By ~ 42

Author(s):

B.L. Lasley ◽

N.M. Loskutoff ◽

G.B. Anderson

Keyword(s):

Assisted Reproduction ◽

Breeding Programs ◽

Conventional Breeding

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Using marker data in conventional breeding programmes: A case of study in selective breeding programs of scallops

Aquaculture ◽

10.1016/j.aquaculture.2007.07.130 ◽

2007 ◽

Vol 272 ◽

pp. S287

Author(s):

V.A. Martinez

Keyword(s):

Selective Breeding ◽

Breeding Programs ◽

Conventional Breeding ◽

Marker Data ◽

Breeding Programmes

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Inheritance of plant height, spike length and number of spikelets per spike in Durum wheat

Zbornik Matice srpske za prirodne nauke ◽

10.2298/zmspn0712027g ◽

2007 ◽

pp. 27-33 ◽

Cited By ~ 1

Author(s):

Biljana Gorjanovic ◽

Marija Kraljevic-Balalic

Keyword(s):

Durum Wheat ◽

Plant Height ◽

Combining Ability ◽

Wheat Breeding ◽

Specific Combining Ability ◽

Spike Length ◽

First Year ◽

Gene Effects ◽

Breeding Programs ◽

Additive Genes

Using the line x tester analysis we studied the combining ability and gene effects of plant height, spike length and number of spikelets per spike in durum wheat. The results of the study show that non-additive genes play more important role than additive genes in the inheritance of plant height, number of spikelets per spike in both years and in inheritance of spike length only in the first year of research. Variety Belfugito, the best general combiner for plant height and number of spikelets per spike, combined well in two best hybrids: Belfugito x Alifen and Belfugito x Yavaros 79, and these hybrids may be used in wheat breeding programs. In the majority of the cases, good specific combining ability (SCA) effects were associated with crosses of two genetically divergent parents having at least one parent as a good general combiner.

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Molecular Characterization and Expression of PFT, an FHB Resistance Gene at the Fhb1 QTL in Wheat

Phytopathology ◽

10.1094/phyto-11-17-0383-r ◽

2018 ◽

Vol 108 (6) ◽

pp. 730-736 ◽

Cited By ~ 15

Author(s):

Yi He ◽

Xu Zhang ◽

Yu Zhang ◽

Dawood Ahmad ◽

Lei Wu ◽

...

Keyword(s):

Defense Responses ◽

Wheat Breeding ◽

Flanking Sequence ◽

Head Blight ◽

Breeding Programs ◽

Diverse Range ◽

Fhb Resistance ◽

Trait Locus ◽

Sumai 3

Fusarium head blight (FHB) is a destructive fungal disease in wheat worldwide. Efforts have been carried out to combat this disease, and the pore-forming toxin-like (PFT) gene at the quantitative trait locus (QTL) Fhb1 was isolated and found to confer resistance to FHB in Sumai 3. In this study, we characterized PFT in 348 wheat accessions. Four haplotypes of PFT were identified. The wild haplotype of PFT had higher resistance than other haplotypes and explained 13.8% of phenotypic variation in FHB resistance by association analysis. PFT was highly expressed during early flowering and increased after Fusarium graminearum treatment in Sumai 3. Analysis of the 5′ flanking sequence of PFT predicted that the cis elements of the PFT promoter were related to hormones and biological defense responses. However, PFT existed not only in the FHB-resistant accessions but also in some susceptible accessions. These results suggested that FHB resistance in a diverse range of wheat genotypes is partially conditioned by PFT. The profiling of FHB resistance and the PFT locus in this large collection of wheat germplasm may prove helpful for incorporating FHB resistance into wheat breeding programs, although more work is needed to reveal the exact role of the QTL Fhb1 in conferring resistance to fungal spread.

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