2,369 research outputs found

    Discovery, Isolation and Characterisation of Promoters from Perennial Ryegrass (\u3ci\u3eLolium Perenne\u3c/i\u3e)

    Get PDF
    The availability of a suite of promoters with a range of spatial, temporal and inducible expression patterns is of significant importance to enable targeted expression of genes of interest for molecular breeding of forage species. A range of resources and tools have been developed for promoter isolation and characterisation in perennial ryegrass (Lolium perenne L.) including genomic lambda and BAC libraries and a 15 K unigene microarray

    Foliar Expression of Candidate Genes Involved in Condensed Tannin Biosynthesis in White Clover (\u3cem\u3eTrifolium Repens\u3c/em\u3e)

    Get PDF
    Bloat disease in cattle and sheep is caused by the rapid microbial degradation of protein-rich fodder in the rumen. This leads to the production of protein foams that trap gases, causing bloat, a condition that is often fatal to livestock and costly to farmers. Condensed tannins (CTs) are phenolic polymers produced by the phenylpropanoid pathway of plants (Figure 1). CTs bind to proteins under acidic to neutral conditions, such as those present in the rumen, slowing their breakdown. A diet with a CT content of between 2% and 4% by dry weight, which is provided by some pasture legumes (e.g. Lotus corniculatus), protects livestock against bloat and improves the absorption of amino acids from the diet. White clover (Trifolium repens L.), a protein rich legume widely used in temperate regions, has virtually no CTs in leaves, although they are present in flowers

    SNP Discovery and Haplotypic Variation in Full-Length Herbage Quality Genes of Perennial Ryegrass (Lolium Perenne L.)

    Get PDF
    The development of forages with enhanced nutritive value through improvements of herbage quality (digestibility, carbohydrate content) is potentially capable of increasing both meat and milk production by up to 25%. However, the expense and time-consuming nature of the relevant biochemical and biophysical assays has limited breeding improvement for forage quality. The development of accurate high-throughput molecular marker-based selection systems such as single nucleotide polymorphisms (SNPs) permits evaluation of genetic variation and selection of favourable variants to accelerate the production of elite new varieties

    Gene-Associated Single Nucleotide Polymorphism (SNP) Discovery in Perennial Ryegrass (\u3cem\u3eLolium Perenne\u3c/em\u3e L.)

    Get PDF
    Perennial ryegrass (Lolium perenne L.) is the most important grass species for temperate pasture systems world-wide. Varietal improvement programs for this obligate outbreeding species are based on polycrossing of multiple parents to produce heterogeneous synthetic populations. The complexity of breeding systems creates challenges and opportunities for molecular marker technology development and implementation. Previous research has led to: the generation of a comprehensive suite of simple sequence repeat (SSR) markers, reference genetic map construction, comparative genetic studies, QTL identification, and population structure analysis. Emphasis has now shifted from the use of anonymous genetic markers linked to trait-specific genes to the development of functionally-associated genetic markers based on candidate genes. The successful implementation of this approach will allow effective selection of parental plants in germplasm collections based on superior allele content

    Integration of Perennial Ryegrass (L. Perenne) Genetic Maps using Gene-Associated SNPs

    Get PDF
    The reference genetic map of perennial ryegrass was developed by the International Lolium Genome Initiative (ILGI), using the p150/112 one-way pseudo-testcross population. A selection of public domain genetic markers including RFLPs, detected by wheat, barley, oat and rice cDNA probes, and AFLPs were mapped, allowing studies of comparative relationships between perennial ryegrass and other Poaceae species. The map was enhanced through the addition of unique perennial ryegrass genomic DNA-derived SSR (LPSSR) markers, providing the basis of framework genetic mapping in other populations. In addition, a small number of RFLP loci detected by candidate genes involved in herbage quality traits were added to the map. A second-generation reference genetic mapping family was developed based on the F1(NA6 x AU6) two-way pseudo-testcross family, generating two parental genetic maps. These maps were populated by genomic SSR loci, EST-RFLP loci and EST-SSR loci (corresponding to multiple functional categories of agronomic importance). A third genetic mapping population based on an interspecific cross between perennial and annual ryegrass genotypes [F1(Andrea1246 x Lincoln1133)] generated a map based on LPSSR and EST-SSR markers. Linkage groups in the two latter maps were inferred using common LPSSR loci with the p150/112 genetic map

    Brassica ASTRA: an integrated database for Brassica genomic research

    Get PDF
    Brassica ASTRA is a public database for genomic information on Brassica species. The database incorporates expressed sequences with Swiss-Prot and GenBank comparative sequence annotation as well as secondary Gene Ontology (GO) annotation derived from the comparison with Arabidopsis TAIR GO annotations. Simple sequence repeat molecular markers are identified within resident sequences and mapped onto the closely related Arabidopsis genome sequence. Bacterial artificial chromosome (BAC) end sequences derived from the Multinational Brassica Genome Project are also mapped onto the Arabidopsis genome sequence enabling users to identify candidate Brassica BACs corresponding to syntenic regions of Arabidopsis. This information is maintained in a MySQL database with a web interface providing the primary means of interrogation. The database is accessible at http://hornbill.cspp.latrobe.edu.au

    Novel Genotypes of the Subtropical Grass \u3cem\u3eEragrostis Curvula\u3c/em\u3e for the Analysis of Apomixis (Diplospory)

    Get PDF
    Eragrostis curvula (Schrad.) Nees is a variable grass native to Southern Africa. Its several forms, known as lovegrasses, were introduced to Australia, USA and Argentina as forage perennial grasses. Apomixis is a common trait in the genus Eragrostis, with diplospory being the most frequent type. Sexual reproduction also occurs in Eragrostis, although not frequently. Since most tetraploid Eragrostis lines are apomictic, the generation of a sexual tetraploid strain is a requirement for linkage analysis of the gene(s) governing the apomictic character. Furthermore, isogenic lines of the same ploidy, reproducing alternatively by sexuality or apomixes, represent an ideal system for comparative transcriptome analysis. The aim of this work was the generation and characterization of two novel genotypes of E. curvula: a dihaploid strain obtained in vitro from an apomictic cultivar and a tetraploid plant derived from the dihaploid after chromosome duplication
    corecore