Eagles H.A.,University of Adelaide |
McLean R.,InterGrain Pty Ltd |
Eastwood R.F.,Australian Grain Technologies |
Appelbee M.-J.,LongReach Plant Breeders |
And 4 more authors.
Crop and Pasture Science | Year: 2014
The Gpc-B1 gene from wild emmer has been proposed as a potential mechanism for improving grain protein in bread wheat without reducing grain yield. Near-isolines with and without the Gpc-B1 gene in three Australian-adapted genetic backgrounds, Gladius, Wyalkatchem and VR1128, were compared in 14 experiments across the south and west of Australia for grain yield, grain protein content and grain weight. The donor parents of Gpc-B1 were the Canadian cultivars Burnside and Somerset. One of the 14 experiments was discarded because of inadequate rust control and confounding effects of Yr36, a gene closely linked to Gpc-B1. Heading date and test weight were measured in five experiments. Across all comparisons, Gpc-B1 increased grain protein content and reduced grain weight, with a negligible effect on grain yield. Selected lines containing Gpc-B1 in a Wyalkatchem background had comparable grain yields to the elite cultivar Mace, but with significantly higher grain protein contents, slightly higher grain weights, similar heading dates and acceptable test weights. The development of agronomically acceptable lines containing Gpc-B1 was partially attributed to the removal of undesirable genes from wild emmer during the breeding of the Canadian donor parents and the use of Australian recurrent parents with high test weights. © 2014 CSIRO.
Mulki M.A.,Max Planck Institute for Plant Breeding Research |
Jighly A.,International Center for Agricultural Research in the Dry Areas |
Ye G.,International Rice Research Institute |
Emebiri L.C.,Graham Center for Agricultural Innovation |
And 3 more authors.
Molecular Breeding | Year: 2013
Soilborne pathogens such as cereal cyst nematode (CCN; Heterodera avenae) and root lesion nematode (Pratylenchus neglectus; PN) cause substantial yield losses in the major cereal-growing regions of the world. Incorporating resistance into wheat cultivars and breeding lines is considered the most cost-effective control measure for reducing nematode populations. To identify loci with molecular markers linked to genes conferring resistance to these pathogens, we employed a genome-wide association approach in which 332 synthetic hexaploid wheat lines previously screened for resistance to CCN and PN were genotyped with 660 Diversity Arrays Technology (DArT) markers. Two sequence-tagged site markers reportedly linked to genes known to confer resistance to CCN were also included in the analysis. Using the mixed linear model corrected for population structure and familial relatedness (Q+K matrices), we were able to confirm previously reported quantitative trait loci (QTL) for resistance to CCN and PN in bi-parental crosses. In addition, we identified other significant markers located in chromosome regions where no CCN and PN resistance genes have been reported. Seventeen DArT marker loci were found to be significantly associated with CCN and twelve to PN resistance. The novel QTL on chromosomes 1D, 4D, 5B, 5D and 7D for resistance to CCN and 4A, 5B and 7B for resistance to PN are suggested to represent new sources of genes which could be deployed in further wheat improvement against these two important root diseases of wheat. © 2012 Springer Science+Business Media B.V.
Gupta S.,Murdoch University |
Li C.,Baron Hay Court |
Loughman R.,Baron Hay Court |
Cakir M.,Murdoch University |
And 2 more authors.
Plant Breeding | Year: 2011
With 2 figures and 4 tables Net type net blotch (NTNB) is an important barley disease in Australia and elsewhere, inducing significant yield reduction. 'WPG8412' was resistant against Australian NTNB isolates 97NB1 and NB73, whereas 'Pompadour' and 'Stirling' showed differential responses to these isolates. Using these lines, three F 1-derived double haploid populations that comprised 194 double haploid lines (DHLs) of 'WPG8412'×'Stirling', 116 DHLs of 'WPG8412'×'Pompadour' and 206 DHLs of 'Pompadour'×'Stirling' were tested against these two isolates. Bimodal segregation indicated a major gene for resistance was operative: in 'WPG8412'×'Stirling' against 97NB1; in 'WPG8412'×'Pompadour' against NB73; and in 'Pompadour'×'Stirling' against either of the isolate. This major gene was mapped using simple sequence repeat (SSR) markers on chromosome 6H in the centromeric region in all three populations. This work demonstrated that 6H region controlling NTNB is a complex locus, where at least three alleles or closely linked genes are possible in these parents against these isolates. This is a first report of 6H complexity for NTNB resistance against Australian isolates. © 2011 Blackwell Verlag GmbH.
Crawford A.C.,Baron Hay Ct |
Crawford A.C.,Murdoch University |
Stefanova K.,Baron Hay Ct |
Lambe W.,Baron Hay Ct |
And 8 more authors.
Theoretical and Applied Genetics | Year: 2011
Flour colour measured as a Commission Internationale de l'Eclairage (CIE) b* value is an important wheat quality attribute for a range of end-products, with genes and enzymes of the xanthophyll biosynthesis pathway providing potential sources of trait variation. In particular, the phytoene synthase 1 (Psy1) gene has been associated with quantitative trait loci (QTL) for flour b* colour variation. Several Psy1 alleles on chromosome 7A (Psy-A1) have been described, along with proposed mechanisms for influencing flour b* colour. This study sought to identify evolutionary relationships among known Psy-A1 alleles, to establish which Psy-A1 alleles are present in selected Australian wheat genotypes and establish their role in controlling variation for flour b* colour via QTL analysis. Phylogenetic analyses showed seven of eight known Psy-A1 alleles clustered with sequences from T. urartu, indicating the majority of alleles in Australian germplasm share a common evolutionary lineage. In this regard, Psy-A1a, Psy-A1c, Psy-A1e and Psy-A1p were common in Australian genotypes with flour b* colour ranging from white to yellow. In contrast Psy-A1s was found to be related to A. speltoides, indicating a possible A-B genome translocation during wheat polyploidisation. A new allele Psy-A1t (similar to Psy-A1s) was discovered in genotypes with yellow flour, with QTL analyses indicating Psy-A1t strongly influences flour b* colour in Australian germplasm. QTL LOD value maxima did not coincide with Psy-A1 gene locus in two of three populations and, therefore, Psy-A1a and Psy-A1p may not be involved in flour colour. Instead two other QTL were identified, one proximal and one distal to Psy-A1 in Australian wheat lines. Comparison of Psy-A1t and Psy-A1p predicted protein sequences suggests differences in putative sites for post-translational modification may influence enzyme activity and subsequent xanthophyll accumulation in the wheat endosperm. Psy-A1a and Psy-A1p were not involved in flour b* colour variation, indicating other genes control variation on chromosome 7A in some wheat genotypes. © 2011 Springer-Verlag.
PubMed | Zhejiang Sci-Tech University, InterGrain Pty Ltd, Government of Western Australia, Murdoch University and Zhejiang Academy of Agricultural Sciences
Type: Journal Article | Journal: BMC genomics | Year: 2016
Barley semi-dwarf genes have been extensively explored and widely used in barley breeding programs. The semi-dwarf gene ari-e from Golden Promise is an important gene associated with some agronomic traits and salt tolerance. While ari-e has been mapped on barley chromosome 5H using traditional markers and next-generation sequencing technologies, it has not yet been finely located on this chromosome.We integrated two methods to develop molecular markers for fine-mapping the semi-dwarf gene ari-e: (1) specific-length amplified fragment sequencing (SLAF-seq) with bulked segregant analysis (BSA) to develop SNP markers, and (2) the whole-genome shotgun sequence to develop InDels. Both SNP and InDel markers were developed in the target region and used for fine-mapping the ari-e gene. Linkage analysis showed that ari-e co-segregated with marker InDel-17 and was delimited by two markers (InDel-16 and DGSNP21) spanning 6.8cM in the doubled haploid (DH) DashVB9104 population. The genetic position of ari-e was further confirmed in the HindmarshW1 DH population which was located between InDel-7 and InDel-17. As a result, the overlapping region of the two mapping populations flanked by InDel-16 and InDel-17 was defined as the candidate region spanning 0.58Mb on the POPSEQ physical map.The current study demonstrated the SLAF-seq for SNP discovery and whole-genome shotgun sequencing for InDel development as an efficient approach to map complex genomic region for isolation of functional gene. The ari-e gene was fine mapped from 10Mb to 0.58Mb interval.
Zhou M.,University of Tasmania |
Johnson P.,University of Tasmania |
Zhou G.,University of Tasmania |
Zhou G.,CSIRO |
And 2 more authors.
Crop Science | Year: 2012
Breeding for waterlogging tolerance is an important and challenging objective in high rainfall areas across many countries in the world, as evaluation of the tolerance in the field is difficult and not reliable. Molecular markers can be effectively used in a breeding program to indirectly select waterlogging tolerance. In this study, 172 doubled haploid (DH) lines originating from a cross of YuYaoXiangTian Erleng (YYXT) and 'Franklin' were used to identify the quantitative trait loci (QTL) controlling waterlogging tolerance. For the purpose of comparing QTL from different DH populations, a consensus map was constructed using six different populations. A total of four QTL were identified, which controlled 6.2 to 30.1% of the phenotypic variation. Among these QTL, one located on chromosome 6H was not identified in previous studies. Two of the QTL were located at similar positions to QTL for salinity tolerance that had been reported earlier. Further analysis showed some relationships between waterlogging and salinity tolerance. Therefore, waterlogging and salinity tolerance can be improved simultaneously by markerassisted selection. © Crop Science Society of America.
Moore C.M.,CSIRO |
Moore C.M.,University of Sydney |
Moore C.M.,Intergrain Pty Ltd |
Richards R.A.,CSIRO |
Euphytica | Year: 2015
The lipid content of wheat is small yet could potentially contribute to increased calorific value of grain delivered for livestock and human consumption. Breeding for greater oil content is required but there is little understanding of the extent or nature of genotypic variation for oil concentration in wheat. A diverse range of commercial and novel spring wheat germplasm was assessed in two years under favourable conditions to understand the extent of genetic variation for lipid content. Genotypic differences were modest in size (4.27–5.32 %) but repeatable across years (rs = 0.71, P < 0.01) reflecting a higher line-mean heritability (0.75). Commercial varieties were intermediate-to-high in their total lipid concentration (mean of 4.82 %) while taller, larger embryo genotypes tended to produce greater lipid concentrations (mean of 4.91 %). Genetic increases in embryo size were associated with moderate increases in oil concentration (rg = 0.38, P < 0.01) while grain yield and oil concentration were uncorrelated (rg = −0.15, P > 0.05). QTL mapping was undertaken in the CD87/Katepwa wheat population phenotyped for grain oil and protein concentration in two years. Both total grain lipid and protein concentrations varied significantly across progeny ranging from 3.87 to 5.77 and 11.3 to 15.6 %, respectively while the ranking of lines for oil content was high (rs = 0.72, P < 0.01) across the 2 years. Nine and 12 QTL were identified for grain lipid and protein concentrations, respectively, with many of the lipid QTL located on the group D chromosomes. Oil and grain protein concentrations were uncorrelated (rg = −0.18, P > 0.05). The identification of diverse wheat sources with higher oil content together with improved genetic understanding suggests potential for genetic improvement of oil content in the development of higher oil wheats. © 2015, Springer Science+Business Media Dordrecht.