Project description:The ditelocentric addition line CS-7EL of the spring wheat (Triticum aestivum) cultivar Chinese Spring (CS) contains the long arm of the chromosome 7E from Thinopyrum elongatum (CS-7EL), which confers high resistance to fusarium head blight. It is of great interest to breeders to integrate the resistance locus (loci) from Th. elongatum into commercial wheat varieties. The objectives of this study were to identify candidate genes expressed from the 7EL chromosome of CS-7EL, to develop 7EL-specific molecular markers, and to validate their usefulness to characterize recombination between one of the group 7 chromosomes of wheat and Th. elongatum. High-throughput sequencing of Fusarium graminearum-infected and control CS and CS-7EL cDNA libraries was performed using RNA-Seq. A stepwise bioinformatics strategy was applied to assemble the sequences obtained from RNA-Seq and to create a conservative list of candidate genes expressed from the foreign chromosome 7EL. PCR primer pairs were designed and tested for 135 candidate genes. A total of 48 expressed molecular markers specific for the chromosome 7EL were successfully developed. Screening of progenies from two BC1F2 families from the cross CS-7E(7D)×2*CSph1b showed that these markers are useful to characterize recombination events between the chromosomes 7D from wheat and 7E from Th. elongatum.
Project description:The ditelocentric addition line CS-7EL of the spring wheat (Triticum aestivum) cultivar Chinese Spring (CS) contains the long arm of the chromosome 7E from Thinopyrum elongatum (CS-7EL), which confers high resistance to fusarium head blight. It is of great interest to breeders to integrate the resistance locus (loci) from Th. elongatum into commercial wheat varieties. The objectives of this study were to identify candidate genes expressed from the 7EL chromosome of CS-7EL, to develop 7EL-specific molecular markers, and to validate their usefulness to characterize recombination between one of the group 7 chromosomes of wheat and Th. elongatum. High-throughput sequencing of Fusarium graminearum-infected and control CS and CS-7EL cDNA libraries was performed using RNA-Seq. A stepwise bioinformatics strategy was applied to assemble the sequences obtained from RNA-Seq and to create a conservative list of candidate genes expressed from the foreign chromosome 7EL. PCR primer pairs were designed and tested for 135 candidate genes. A total of 48 expressed molecular markers specific for the chromosome 7EL were successfully developed. Screening of progenies from two BC1F2 families from the cross CS-7E(7D)×2*CSph1b showed that these markers are useful to characterize recombination events between the chromosomes 7D from wheat and 7E from Th. elongatum. Expression profiling of inoculated rachis from CS and CS-7EL heads sampled at 4 days after inoculation. Inoculation of all developed spikelets on each head at mid-anthesis was done with either water or F. graminearum strain DAOM 180378. Three biological replicates were done for each treatment, and 10 to 12 heads were inoculated per biological replicate.
Project description:Fusarium head blight (FHB) is a major disease of cereal crops caused by the fungus Fusarium graminearum (Fg). FHB affecting the flowering heads (or spikes). A FHB resistance locus has been identified on the chromosome 7E of the wild wheat relative Thinopyrum elongatum (Th.e.). That chromosome (7E) or a long arm fragment of it (7EL) have been transferred as additions in the wheat background 'Chinese Spring' (CS). The two addition lines are resistant to FHB while 'Chinese Spring' is moderately susceptible to it. The mechanism of resistance is not known. The analysis of this work is published in the Canadian Journal of Plant Pathology (Wang et al, 2010).
Project description:Purpose: Next-generation sequencing (NGS) has revolutionized systems-based analysis of cellular pathways. The goals of this study are to compare NGS-derived Triticum aestivum transcriptome (RNA-seq) profiling methods and to evaluate genotypes associated with resistance against the Wheat dwarf virus. Methods: Triticum aestivum mRNA profiles of genotypes associated with resistance against the Wheat dwarf virus were generated by deep sequencing, in four replicates, using Illumina. The sequence reads that passed quality filters were analyzed at the transcript isoform level with two methods: Burrows–Wheeler Aligner (BWA) followed by ANOVA (ANOVA) and TopHat followed by Cufflinks. qRT–PCR validation was performed using TaqMan and SYBR Green assays. Conclusions: Our study represents the first detailed analysis of Triticum aestivum transcriptomes, with biologic replicates, generated by RNA-seq technology. The optimized data analysis workflows reported here should provide a framework for comparative investigations of expression profiles. Our results show that NGS offers a comprehensive and more accurate quantitative and qualitative evaluation of mRNA and miRNA content within a cell or tissue. We conclude that RNA-seq based transcriptome characterization would expedite genetic network analyses and permit the dissection of complex biologic functions.
Project description:Fusarium head blight (FHB) is a major disease of cereal crops caused by the fungus Fusarium graminearum (Fg). FHB affecting the flowering heads (or spikes). A FHB resistance locus has been identified on the chromosome 7E of the wild wheat relative Thinopyrum elongatum (Th.e.). That chromosome (7E) or a long arm fragment of it (7EL) have been transferred as additions in the wheat background 'Chinese Spring' (CS). The two addition lines are resistant to FHB while 'Chinese Spring' is moderately susceptible to it. The mechanism of resistance is not known. The analysis of this work is published in the Canadian Journal of Plant Pathology (Wang et al, 2010). We used the wheat microarray to determine the global expression profil in inoculated spikelets of the addition and parental lines, after water or Fg treatment, with samplings at 2 and 4 days after inoculation (DAI).