Agronomy and Crop Sciences Commons^™

Integration Of Perennial Ryegrass (L. Perenne) Genetic Maps Using Gene-Associated Snps, A. C. Vecchies, R. C. Ponting, M. C. Drayton, N. O. I. Cogan, K. F. Smith, G. C. Spangenberg, J. W. Forster

International Grassland Congress Proceedings

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 …

Construction And Comparison Of Genetic Linkage Maps Of Four F1 Populations Of Italian Ryegrass (Lolium Multiflorum Lam.), M. Vandewalle

International Grassland Congress Proceedings

The objective of this work was to integrate genetic maps and QTL-positions within 4 two-way pseudo-testcross F1 populations (each 110 genotypes) of Italian ryegrass (Lolium multiflorum) To integrate genetic maps and QTL-positions within the 4 populations and to the ILGI reference map, the maps used for initial QTL-analysis and marker assisted selection for yield and for different quality traits were further evaluated.

Qtls For Morphogenetic Traits In Medicago Truncatula, B. Julier, T. Huguet, J. M. Prosperi, P. Barre, Christian Huyghe, G. Cardinet

International Grassland Congress Proceedings

Plant morphogenesis that includes growth, development and flowering date, drives a large number of agronomical important traits in both grain and forage crops. Quantitative trait locus (QTL) mapping is a way to locate zones of the genome that are involved in the variations observed in a segregating population. Co-location of QTLs and candidate genes is an indication of the involvement of the genes in the variation. The objective of this study was to analyse segregation of aerial morphogenetic traits in a mapping population of recombinant inbred lines of the model legume species M. truncatula , to locate QTLs and candidate …

A Comprehensive Analysis Of Gene Expression And Genomic Alterations In A Newly Formed Autotetraploid Of Paspalum Notatum, L. G. Martelotto, J. P. A. Ortiz, F. Espinoza, C. L. Quarin, S. C. Pessino

International Grassland Congress Proceedings

The proportion of angiosperms that have experienced one or more episodes of chromosome doubling is estimated to be of the order of 50-70%. This prominence of polyploidy probably implies some adaptive significance. The emergence of novel phenotypes could allow polyploids to enter new niches or enhance their chances of being selected for use in agriculture. Although the causes of novel variation in polyploids are not well understood, they could involve changes in gene expression through dosage-regulation, altered regulatory interactions and rapid genetic/epigenetic changes. The objective of this work was to carry out an extensive transcript profiling and genome analysis of …

Effects Of Sowing Date And Phosphorus Fertiliser Application On Winter Survival Of Lucerne Cv. Aohan In The Northern Semi-Arid Region Of China, Z. L. Wang, Q. Zh. Sun, Y. W. Wang, Zh. Y. Li, Sh. F. Zhao

International Grassland Congress Proceedings

In the northern semi-arid region of China, winter survival is always a limiting factor for lucerne production, because low temperatures and a dry climate in winter (Zhou et al., 1993; Ma, 2000; Sun & Gui, 2001; Sun et al., 2003). An experiment was conducted to find an appropriate sowing date and P application rate in order to improve lucerne winter survival.

Characterisation Of Perennial Ryegrass Parental Inbred Lines For Generating Recombinant Inbred Lines For Fine Mapping And Gene Cloning, U. C. M. Anhalt, S. Barth, T. Schwarzacher, J. S. Heslop-Harrison

International Grassland Congress Proceedings

Intermated recombinant inbred lines (IRIs) are a powerful tool for fine mapping and cloning of genes. Such population structures have been particularly helpful for cloning of genes in the model genetic plant Arabidopsis thaliana. IRIs or recombinant inbred lines (RILs) would be valuable for perennial ryegrass (Lolium perenne), but its allogamous character means that the construction of RILs is a difficult task. The international Lolium community would benefit from the development of such lines. The aims of the projects are to characterise the parental lines and initial generations at the (1) phenotypic, (2) molecular and (3) molecular …

A High-Density Ssr Linkage Map Of Red Clover And Its Transferability To Other Legumes, S. Isobe, S. Sato, E. Asamizu, I. Klimenko, N. N. Kozlov, K. Okumura, S. Tabata

International Grassland Congress Proceedings

A high-density linkage map of red clover was constructed based on SSR and RFLP markers. In order to construct a linkage map with user (breeder) friendly markers; i.e. informative and easy detection, two policies were adopted for marker development. One was that the markers should be derived from cDNA or gene-rich regions, and the other was that the SSR markers should be detected polymorphisms on agarose gels. We also discuss the transferability of the markers on the map to other red clover germplasm and legumes. Such highly transferable markers could be used to screen anchor markers for both on a …

Development Of Est And Aflp Markers Linked To A Gene For Resistance To Ryegrass Blast (Pyricularia Sp.) In Italian Ryegrass (Lolium Multiflorum Lam.), Y. Miura, C. Ding, R. Ozaki, M. Hirata, M. Fujimori, H. Cai, K. Mizuno

International Grassland Congress Proceedings

Ryegrass blast, caused by the fungus Pyricularia sp. is one of the most serious diseases of Italian ryegrass (Lolium multiflorum Lam.). However, in Italian ryegrass, except for a new cultivar ‘Sachiaoba’, no resistant cultivars were found in Japan (Mizuno et al., 2003). For these reasons, improving the disease resistance of Italian ryegrass is one of the most important goals in the breeding programs. The aim of this study was to identify genes for resistance to ryegrass blast and to develop EST and AFLP markers linked tightly to the resistance genes.

Qtl Analysis And Trait Dissection In Ryegrass (Lolium Spp.), T. Yamada, J. W. Forster

International Grassland Congress Proceedings

Key points

1. Molecular marker-based genetic analysis permits the dissection of complex phenotypes through resolution of the locations of pleiotropic and interacting genetic factors.
2. Several QTLs for agronomically important characters such as flowering time, winter hardiness and forage quality have been identified in perennial ryegrass by molecular marker-based map analysis.
3. Some QTLs were putatively orthologous to those for equivalent traits in cereals.
4. The identification of co-location between QTLs and functionally-associated genetic markers is critical for the future implementation of marker-assisted selection programs.

Construction And Exploitation Of A Bacterial Artificial Chromosome (Bac) Library For Lolium Perenne (Perennial Ryegrass), K. Farrar, A. M. Thomas, M. O. Humphreys, I. S. Donnison

International Grassland Congress Proceedings

BAC libraries are an important tool in genomics, enabling physical maps, genome sequencing, marker development and map based cloning strategies. A BAC library has therefore been generated for the temperate grass species Lolium perenne (perennial ryegrass) which compliments an existing BAC library of the closely related species, Festuca pratensis also generated by IGER. Moreover the L. perenne BAC library will provide a useful tool for grass comparative genomics to compliment the existing BAC libraries of cereal crops including rice, wheat, barley, Sorghum and maize. In particular it will allow a comparison of micro-synteny between this large genome forage crop species …

Introgression Mapping In The Grasses, I. P. King, J. King, I. P. Armstead, J. A. Harper, L. A. Roberts, H. Thomas, H. J. Ougham, R. N. Jones, A. Thomas, B. J. Moore, L. Huang, I. S. Donnison

International Grassland Congress Proceedings

Key points

1. Lolium perenne/Festuca pratensis hybrids and their derivatives provide an ideal system for intergeneric introgression.
2. The Lolium perenne/Festuca pratensis system is being exploited to elucidate genome organisation in the grasses, determination of the genetic control of target traits and the isolation of markers for MAS in breeding programmes.
3. The potential of the system as an aid to contig the Lolium and Festuca genomes and for gene isolation is discussed.

Application Of Molecular Technologies In Forage Plant Breeding, K. F. Smith, J. W. Forster, M. P. Dobrowolski, N. O. I. Cogan, N. R. Bannan, E. Van Zijll De Jong, M Emmerling, G. C. Spangenberg

International Grassland Congress Proceedings

Key points

1. A range of molecular breeding technologies have been developed for forage plant species including both transgenic and non-transgenic methodologies.
2. The application of these technologies has the potential to greatly increase the range of genetic variation that is available for incorporation into breeding programs and subsequent delivery to producers in the form of improved germplasm.
3. Further developments in detailing the phenotypic effect of genes and alleles both through research in target species and through inference from results from model species will further refine the delivery of new forage cultivars.

Application Of Molecular Markers In Genetic Resources Management Of Perennial Ryegrass, R. Van Treuren

International Grassland Congress Proceedings

Key points

1. Molecular markers are effective tools to support traditional approaches in plant genetic resources management.
2. Genetic diversity assessed for perennial ryegrass by AFLP analysis revealed differentiation of populations occurring in traditional Dutch grasslands from commercial varieties, but not from populations occurring in Dutch nature reserves.
3. No specific conservation measures were recommended to maintain the genetic diversity of perennial ryegrass occurring in traditional Dutch grasslands.
4. Pollination rates estimated by microsatellite analysis for a rejuvenated population of a perennial ryegrass genebank accession were very well described by an inverse quadratic function of inter-plant distance between potential mating pairs, while recorded flowering …

A Computational Pipeline For The Development Of Comparative Anchor Tagged Sequence (Cats) Markers, J. Schauser, J. Fredslund, L. Heegaard Madsen, Niels Sandal, Jens Stougaard

International Grassland Congress Proceedings

Key points:

1. Molecular markers that allow the transfer of map information from one species to another are vital in comparative genetics.
2. To identify potential anchor marker sequences more efficiently, we have established a bioinformatic pipeline that combines multi-species EST- and genome- sequence data.
3. Taking advantage of information from a few related species, comparative EST sequence analysis identifies evolutionary conserved sequences in less well-characterised species in the same family.
4. Alignment of evolutionary conserved EST sequences with corresponding genomic sequences defines sets of PCR primer sites flanking introns.
5. Markers identified by this procedure will be readily transferable to other species since they …

Leaves Of High Yielding Perennial Ryegrass Contain Less Aggregated Rubisco Than S23, A. Kingston-Smith, P. W. Wilkins

International Grassland Congress Proceedings

Breeding diploid perennial ryegrass for improved dry matter yield under nitrogen-limiting conditions has reduced the nitrogen (N) concentration of the herbage (Wilkins et al., 2003). Reduced N concentration in the ruminant diet is one potential way to reduce losses of N to the environment by reducing the amount of N that animals excrete. The underlying physiological basis of this increased N-use efficiency in ryegrass was investigated.

Variability In Quantity And Composition Of Water Soluble Carbohydrates Among Irish Accessions And European Varieties Of Perennial Ryegrass, S. Mcgrath, S. Barth, A. Frohlich, M. Francioso, S. A. Lamorte, T. R. Hodkinson

International Grassland Congress Proceedings

The objective of this study was to identify perennial ryegrass accessions displaying high fructose and glucose contents and an improved ratio between fructose and glucose fractions across different time points throughout the year. Fructose and glucose are the main constituents of the water soluble carbohydrate (WSC) fraction in perennial ryegrass. For animal nutrition the amount of WSC is crucial as it is the primary energy source available to metabolise the intake of plant protein. The ratio between fructose and glucose fractions is important since fructosan chains, which are an excellent energy source for ruminants, are built from fructose. Furthermore the …

Introgression Breeding For Improvement Of Winter Hardiness In Lolium /Festuca Complex Using Androgenenesis, T. Yamada, Y. D. Guo, Y. Mizukami

International Grassland Congress Proceedings

Intergeneric hybrids between closely related Lolium and Festuca species are used to broaden the gene pool and provide plant breeders with options to combine complementary traits to develop robust but high quality grass varieties. Androgenesis was found to be an effective procedure for selecting Lolium-Festuca genotypes comprising gene combinations rarely or never recovered by conventional backcross breeding programs. Here we describe the optimisation of androgenesis in Lolium perenne x Festuca pratensis. The male fertility and freezing tolerance of the Festulolium microspore-derived progenies were analysed and these progenies were also analysed by using genomic in situ hybridisation (GISH). The object …

Studies Of Seed Characteristics Of Ecotypes Of Lucerne, Bromus And Agropyron In Response To Fusarium Oxysporum And F. Solani, M. A. Alizadeh

International Grassland Congress Proceedings

Vigorous seeds and seedlings are more resistant to pathogens than non-vigorous seeds and seedlings (Kim, 1994). Therefore, it is necessary to assess seed and seedling performance in response to seed borne fungi.

A New Napier Grass Stunting Disease In Kenya Associated With Phytoplasma, A. B. Orodho, S. I. Ajanga, P. Jones, P. O. Mudavadi

International Grassland Congress Proceedings

Napier grass (Pennisetum purpureum Schum) is a cultivated elephant grass native to Eastern and Central Africa forming the major livestock feed on East African smallholder dairy farms (Valk, 1990) as it is suitable for cut and carry zero-grazing management systems. Although several plant pathogens have been described historically they were seldom severe. However, in the 1970s there was an outbreak of snow mould fungal disease caused by Beniowskia spheroidea that attacked most varieties of napier grass. A napier grass variety (clone 13) was bred which is resistant to the disease. In the 1990s two major outbreaks of napier grass …

Genetic Analysis Of The Interaction Between The Host Perennial Ryegrass And The Crown Rust Pathogen (Puccinia Coronata F.Sp. Lolii), P. M. Dracatos, J. L. Dumsday, R. S. Olle, N. O. I. Cogan, M. P. Dobrowolski, K. F. Smith, J. W. Forster

International Grassland Congress Proceedings

Crown rust (Puccinia coronata f.sp lolii) is the most important fungal pathogen of perennial ryegrass (L.perenne L.). The physiological effects associated with infection include reduction of water soluble carbohydrate (WSC) reserves, causing decreased dry matter yield, digestibility and palatability for herbivores reared for meat, milk and wool production. Phenotypic variability of rust-infection in perennial ryegrass is likely to be due to environmental effects, as well as the interaction of defence and resistance genes in the grass and virulence genes in the pathogen. Classical and molecular genetic marker-based studies have previously detected both qualitative and quantitative resistance, due respectively …