Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 30 of 31
Full-Text Articles in Physical Sciences and Mathematics
Plantain (Plantago Lanceolata L.) Growth Islimited Under Waterlogging, S. S. Wilson, Daniel J. Donaghy, D. J. Horne, Soledad Navarrete, P. D. Kemp
Plantain (Plantago Lanceolata L.) Growth Islimited Under Waterlogging, S. S. Wilson, Daniel J. Donaghy, D. J. Horne, Soledad Navarrete, P. D. Kemp
IGC Proceedings (1997-2023)
Plantain (Plantago lanceolata L.; PL) is becoming an increasingly important component of New Zealand dairy pastures because of its ability to reduce nitrogen losses to the environment. However, widespread suggestions of its poor persistence, have led to industry concern over its suitability for dairy systems. Anecdotal evidence suggests that PL does not cope well in waterlogged soil, yet there is little scientific literature relevant to this issue. Thus, the aim of this study was to investigate the impact of waterlogging stress on PL growth and survival. In a glasshouse, the performance of PL under waterlogging was evaluated against perennial …
Enhancing Water Use Efficiency On Irrigated Dairy Pastures With Nitrogen Fertiliser, Frank R. Mckenzie, J. L. Jacobs, G. N. Ward
Enhancing Water Use Efficiency On Irrigated Dairy Pastures With Nitrogen Fertiliser, Frank R. Mckenzie, J. L. Jacobs, G. N. Ward
IGC Proceedings (1997-2023)
Low summer rainfall in southwest Victoria, Australia, restricts pasture growth and limits milk production. One fifth of dairy farmers in the region have some capacity to irrigate during summer. Irrigated dairy pastures are relatively poor utilisers of water with water use efficiencies (WUE) of about 1 t DM/ML water (Ward et al. 1998). Using nitrogen (N) fertiliser may increase dry matter (DM) yields for a given amount of water. Data on N response efficiencies from irrigated pasture in southwest Victoria are lacking. Two experiments determined the potential of N fertiliser to maximise the conversion of irrigated water to pasture …
Responses Of Irrigated Pasture Nutritive Characteristics To Summer Nitrogen Fertiliser, Frank R. Mckenzie, J. L. Jacobs, G. N. Ward
Responses Of Irrigated Pasture Nutritive Characteristics To Summer Nitrogen Fertiliser, Frank R. Mckenzie, J. L. Jacobs, G. N. Ward
IGC Proceedings (1997-2023)
Low summer rainfall in southwest Victoria, Australia, restricts pasture growth and reduces pasture nutritive value thereby limiting potential milk production. One fifth of dairy farmers in the region have some capacity to irrigate during summer and nitrogen (N) fertiliser is used to enhance pasture dry matter (DM) yield. Data on the effects of N fertiliser on irrigated pasture nutritive characteristics during summer in southwest Victoria are lacking. Two experiments determined the potential of N fertiliser to improve pasture nutritive (crude protein, CP and metabolisable energy, ME) value during summer.
Yield Progress Of Perennial Ryegrass And Silage Maize - Genetic Gain Or Climate Change?, Antje Herrmann, A. Kornher, Friedhelm Taube
Yield Progress Of Perennial Ryegrass And Silage Maize - Genetic Gain Or Climate Change?, Antje Herrmann, A. Kornher, Friedhelm Taube
IGC Proceedings (1997-2023)
Gains in annual dry matter yield (DMY) from breeding achieved during the last decades are reported to range between 2.5 and 6% per decade for perennial ryegrass (Wilkins & Humphreys, 2003). In contrast, accelerated progress in improving DMY has been achieved for silage maize, varying between 8 and 13% per decade (Lauer et al., 2001). These gains are mainly attributed to (i) genetic yield potential increase, (ii) improved crop management and (iii) increased stress tolerance. The potential impact of climate change on yield progress, however, is disregarded in most studies. The objective of this study therefore was to quantify …
The Effect Of Extremes In Soil Moisture Content On Perennial Ryegrass Growth, A. Scott Laidlaw
The Effect Of Extremes In Soil Moisture Content On Perennial Ryegrass Growth, A. Scott Laidlaw
IGC Proceedings (1997-2023)
Seasonal distribution of rainfall in the UK and Ireland is predicted to become more variable (Sweeney, 2003). The problems of excessive soil moisture on grass utilisation and the effect of deficit in soil moisture on grass growth are well known. However the effect of excess rainfall on the growth of sown grass is less clear and is usually not taken into account in grass growth models. This study was carried out to investigate the potential impact of excess moisture on perennial ryegrass growth in the field and to investigate the relative effect of soil moisture varying from deficit to excess …
Water Soluble Carbohydrate Content Of Two Cultivars Of Perennial Ryegrass (Lolium Perenne) At Eight European Sites, Magnus A. Halling, A. C. Longland, S. D. Martens, L. Nesheim, P. O'Kiely
Water Soluble Carbohydrate Content Of Two Cultivars Of Perennial Ryegrass (Lolium Perenne) At Eight European Sites, Magnus A. Halling, A. C. Longland, S. D. Martens, L. Nesheim, P. O'Kiely
IGC Proceedings (1997-2023)
Grasses with high levels of WSC have been shown to enhance livestock production (Miller et al., 1999). This has led to the development of perennial ryegrass (PRG) cultivars that can accumulate high levels of WSC. The aim of this experiment was to determine if the genetic potential to accumulate high levels of WSC was expressed under varying conditions.
Agronomic Value Of Mixture Of Perennial Rye-Grass Cultivars: Preliminary Results, W. G. Do Nascimento, F. Surault, J. C. Emile, Christian Huyghe
Agronomic Value Of Mixture Of Perennial Rye-Grass Cultivars: Preliminary Results, W. G. Do Nascimento, F. Surault, J. C. Emile, Christian Huyghe
IGC Proceedings (1997-2023)
Mixtures of grass and legume species are commonly used in sown grasslands. Mixtures have been shown to be favourable for stable production over cycles and years due to a succession of species over time (Mosimann & Charles, 1996 ; Nie et al, 2004). However, little is known whether the genetic variation in pure stands has an influence on the agronomic value and its variation over seasons.
Black Medick - A Beneficial Companion Crop For Use In Organic Grass Production, R. Macháč, B. Cagaš
Black Medick - A Beneficial Companion Crop For Use In Organic Grass Production, R. Macháč, B. Cagaš
IGC Proceedings (1997-2023)
Organic farmers must use only organically produced seed for establishing new meadows and for, renovation and undersowing of old pastures, in accordance with EC regulations. Therefore an important and difficult goal is to obtain enough seed of grasses without the use of pesticides and inorganic fertilisers. The seed yield is closely related to the number of fertile tillers, which depends on adequate nitrogen in the soil. Growing grasses for seed with a legume, as a companion crop, is one possibility for providing a source of organic nitrogen. Aamlid (1999) claimed that growing timothy together with white clover or alsike clover …
The Effect Of Nitrogen Fertiliser And Season On The In Situ Degradability Of Irish Perennial Ryegrass In Cattle, V. Olsson, J. J. Murphy, F. P. O'Mara, K. O'Connell, J. Humphreys, F. J. Mulligan
The Effect Of Nitrogen Fertiliser And Season On The In Situ Degradability Of Irish Perennial Ryegrass In Cattle, V. Olsson, J. J. Murphy, F. P. O'Mara, K. O'Connell, J. Humphreys, F. J. Mulligan
IGC Proceedings (1997-2023)
In light of increasing environmental and economic pressure on agriculture to utilise resources more efficiently, protein feeding and its effects are fundamentally important. As grazed grass is the predominant feed in Irish dairy and beef cattle production systems, it is necessary to establish protein values for different grass varieties and cultivars fed. It is also important to investigate the extent of ruminal nitrogen (N) degradability for these grasses since this characteristic greatly influences environmentally damaging urinary N excretion.
Fibre Degradation Rate Of Perennial Ryegrass Varieties Measured Using Three Techniques: In Situ Nylon Bag, In Vivo Rumen Evacuation And In Vitro Gas Production, H. Z. Taweel, B. M. Tas, B. A. Williams, A. Elgersma, J. Dijkstra, S. Tamminga
Fibre Degradation Rate Of Perennial Ryegrass Varieties Measured Using Three Techniques: In Situ Nylon Bag, In Vivo Rumen Evacuation And In Vitro Gas Production, H. Z. Taweel, B. M. Tas, B. A. Williams, A. Elgersma, J. Dijkstra, S. Tamminga
IGC Proceedings (1997-2023)
In Western Europe, perennial ryegrass is the most widely used grass species for grazing cattle, because of its high productivity, palatability and nutritive value. However, the low dry matter intake (DMI) of perennial ryegrass pasture has been identified as a major factor limiting milk production of high producing dairy cows. Altering the chemical, physical and mechanical characteristics that contribute to its low DMI through grass breeding and the choice of variety may be a way forward in trying to maximise its DMI. This study aimed to examine whether perennial ryegrass varieties differ in their NDF degradation rates (kdNDF).
Perennial Ryegrass Variety Differences In Nutritive Value Characteristics, T. J. Gilliland, R. E. Agnew, A. M. Fearon, F. E. A. Wilson
Perennial Ryegrass Variety Differences In Nutritive Value Characteristics, T. J. Gilliland, R. E. Agnew, A. M. Fearon, F. E. A. Wilson
IGC Proceedings (1997-2023)
Animal grazing performance at grass is predominately determined by herbage intake rates, with high yielding dairy cows requiring up to 20 kg/d DM within a limited grazing time (Gibb, 1998). Grass nutritional factors such as seasonal patterns in digestibility and water-soluble carbohydrate levels have been linked to animal productivity (Davies et al., 1991), while sward surface height, herbage mass, bulk density and green leaf mass have been shown to promote high grazing intake (Barrett et al., 2001). Furthermore, fatty acid profiles have been shown to improve the unsaturated fatty acid composition of milk, with potential human health benefits …
The Nutritional Value Of Cocksfoot (Dactylis Glomerata L.) And Perennial Ryegrass (Lolium Perenne L.) Under Leaf-Stage Based Defoliation Management, L. R. Turner, D. J. Donaghy, P. A. Lane
The Nutritional Value Of Cocksfoot (Dactylis Glomerata L.) And Perennial Ryegrass (Lolium Perenne L.) Under Leaf-Stage Based Defoliation Management, L. R. Turner, D. J. Donaghy, P. A. Lane
IGC Proceedings (1997-2023)
The perception that cocksfoot is of lower nutritional value and less productive than perennial ryegrass is largely the result of studies in which management was based on perennial ryegrass (to the detriment of cocksfoot) or involved defoliation of both species at the same time (Greenhalgh & Reid, 1969; Johnson & Thomson, 1996). Maintaining plants in a vegetative state through species-specific management is essential to retain the high quality and productivity of cocksfoot. Defoliation at or before 4-5 fully expanded live leaves per tiller is recommended as the ideal physiological regrowth stage for defoliation of cocksfoot, resulting in metabolisable energy (ME) …
Population Genetics Of Perennial Ryegrass (Lolium Perenne L.): Differentiation Of Pasture And Turf Cultivars, M. P. Dobrowolski, N. R. Bannan, R. C. Ponting, J. W. Forster, K. F. Smith
Population Genetics Of Perennial Ryegrass (Lolium Perenne L.): Differentiation Of Pasture And Turf Cultivars, M. P. Dobrowolski, N. R. Bannan, R. C. Ponting, J. W. Forster, K. F. Smith
IGC Proceedings (1997-2023)
Cultivar differentiation using molecular markers to assess genetic variation may be of value in obtaining or protecting plant breeders rights. A knowledge of genetic variation and how it is structured within perennial ryegrass (Lolium perenne L.) populations will also help us understand the consequences to fitness and adaptation when implementing molecular breeding strategies. In a study of the population genetic structure of a number of perennial ryegrass varieties we examined the cultivar differentiation potential of marker technology.
Mapping Water-Soluble Carbohydrate Content In Perennial Ryegrass, L. Turner, J. Gallagher, I. P. Armstead, A. Cairns, M. O. Humphreys
Mapping Water-Soluble Carbohydrate Content In Perennial Ryegrass, L. Turner, J. Gallagher, I. P. Armstead, A. Cairns, M. O. Humphreys
IGC Proceedings (1997-2023)
Perennial ryegrass (Lolium perenne L.) is the main species used in UK agriculture and shows considerable genetic variation for water-soluble carbohydrate (WSC) content (Humphreys, 1989, Turner et al., 2001, 2002). High-sugar grasses have already proved useful in UK livestock production (Miller et al., 2001), but can be unpredictable in the field. Increased understanding of carbon partitioning in ryegrass would benefit future breeding programmes.
Discovery, Isolation And Characterisation Of Promoters From Perennial Ryegrass (Lolium Perenne), A. Lidgett, N. Petrovska, J. Chalmers, N. Cummings, G. C. Spangenberg
Discovery, Isolation And Characterisation Of Promoters From Perennial Ryegrass (Lolium Perenne), A. Lidgett, N. Petrovska, J. Chalmers, N. Cummings, G. C. Spangenberg
IGC Proceedings (1997-2023)
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.
Agrobacterium Tumefaciens-Mediated Transformation Of Perennial Ryegrass (Lolium Perenne L.), H. Sato, M. Fujimori, Y. Mano, T. Kiyoshi, T. Takamizo
Agrobacterium Tumefaciens-Mediated Transformation Of Perennial Ryegrass (Lolium Perenne L.), H. Sato, M. Fujimori, Y. Mano, T. Kiyoshi, T. Takamizo
IGC Proceedings (1997-2023)
An Agrobacterium tumefaciens-mediated transformation method has several advantages. However, this method has no example of success in perennial ryegrass (Lolium perenne L.). Since Lolium species are outcrossing, one cultivar consists of many genotypes. Each genotype can show a different ability for callus formation and plant regeneration (Takahashi et al., 2004). Thus, it is important to select a good genotype for efficient and stable transformation. If the plant is maintained in vitro, we can perform transformation using calli induced from shoot tips of the same genotype at any time. Our objective is to confirm an A. tumefaciens …
Isolation And Characterisation Of Genes Encoding Ice Recrystallisation Inhibition Proteins (Irips) In The Cryophilic Antarctic Hair-Grass (Deschampsia Antarctica) And The Temperate Perennial Ryegrass (Lolium Perenne), U. P. John, R. M. Polotnianka, K. A. Sivakumaran, L. Mackin, M. J. Kuiper, J. P. Talbot, O. Chew, G. D. Nugent, N. O. I. Cogan, M. C. Drayton, J. W. Forster, G. E. Schrauf, G. C. Spangenberg
Isolation And Characterisation Of Genes Encoding Ice Recrystallisation Inhibition Proteins (Irips) In The Cryophilic Antarctic Hair-Grass (Deschampsia Antarctica) And The Temperate Perennial Ryegrass (Lolium Perenne), U. P. John, R. M. Polotnianka, K. A. Sivakumaran, L. Mackin, M. J. Kuiper, J. P. Talbot, O. Chew, G. D. Nugent, N. O. I. Cogan, M. C. Drayton, J. W. Forster, G. E. Schrauf, G. C. Spangenberg
IGC Proceedings (1997-2023)
Antarctic hairgrass (D. antarctica Desv.), the only grass species indigenous to Antarctica, has a well developed tolerance of freezing, strongly induced by cold-acclimation. In response to low temperatures D. antarctica exhibits recrystallisation inhibition (RI) activity, localised to the apoplasm, that prevents further growth of ice crystals following freezing.
Gene Discovery And Molecular Dissection Of Lignin Biosynthesis In Perennial Ryegrass (Lolium Perenne), A. Lidgett, M. Emmerling, R. Heath, R. Mcinnes, D. Lynch, A. Bartkowski, K. Fulgueras, T. Sawbridge, E. K. Ong, K. F. Smith, A. Mouradov, G. C. Spangenberg
Gene Discovery And Molecular Dissection Of Lignin Biosynthesis In Perennial Ryegrass (Lolium Perenne), A. Lidgett, M. Emmerling, R. Heath, R. Mcinnes, D. Lynch, A. Bartkowski, K. Fulgueras, T. Sawbridge, E. K. Ong, K. F. Smith, A. Mouradov, G. C. Spangenberg
IGC Proceedings (1997-2023)
Lignification of plant cell walls has been identified as a major factor limiting forage digestibility. It limits the amount of digestible energy available to livestock, resulting in an incomplete utilisation of cellulose and hemicellulose by ruminant animals. Modification of the lignin profile of ryegrasses (Lolium spp.) and fescues (Festuca spp.) is undertaken through modulating the expression of genes encoding enzymes involved in the biosynthesis of monolignols.
A Proposal For An International Transcriptome Initiative For Forage And Turf: Microarray Tools For Expression Profiling In Ryegrass, Clover And Grass Endophytes, T. Webster, N. Nguyen, C. Rhodes, S. A. Felitti, R. Chapman, D. Edwards, G. C. Spangenberg
A Proposal For An International Transcriptome Initiative For Forage And Turf: Microarray Tools For Expression Profiling In Ryegrass, Clover And Grass Endophytes, T. Webster, N. Nguyen, C. Rhodes, S. A. Felitti, R. Chapman, D. Edwards, G. C. Spangenberg
IGC Proceedings (1997-2023)
Knowledge of the expression pattern of genes provides a valuable insight into gene function and role in determining the observed heritable phenotype. High–density cDNA and oligonucleotide microarrays represent powerful tools for transcriptome analysis to gain an understanding of gene expression patterns for thousands of genes. Internationally coordinated efforts in transcriptome analyses and sharing of microarray resources will benefit the advancement of our understanding of gene function in forage and turf species.
Ryegrass Astra: A Web-Based Resource For Lolium Est Analysis, G. C. Spangenberg, T. Sawbridge, E. K. Ong, C. G. Love, T. A. Erwin, E. G. Logan, D. Edwards
Ryegrass Astra: A Web-Based Resource For Lolium Est Analysis, G. C. Spangenberg, T. Sawbridge, E. K. Ong, C. G. Love, T. A. Erwin, E. G. Logan, D. Edwards
IGC Proceedings (1997-2023)
Perennial ryegrass (Lolium perenne L.) is a major grass species of temperate pastoral agriculture.
Development And Testing Of Novel Chloroplast Markers For Perennial Ryegrass From De Novo Sequencing And In Silico Sequences, S. Mcgrath, T. R. Hodkinson, S. Barth
Development And Testing Of Novel Chloroplast Markers For Perennial Ryegrass From De Novo Sequencing And In Silico Sequences, S. Mcgrath, T. R. Hodkinson, S. Barth
IGC Proceedings (1997-2023)
Chloroplast DNA is uniparentally inherited and non-recombinant in Lolium perenne. These properties make the chloroplast genome a useful tool for studying inter- and intra- specific relationships. Previous genetic studies on L. perenne have used chloroplast sequence data. However, the relative lack of variation in the chloroplast genome limits its usefulness for analysis at the single individual level within a species. However, chloroplast SSR markers have recently been shown to have high levels of polymorphism (Provan et al., 2004). This is the first study to design and employ such markers for L. perenne. The objectives of this study …
Microarray-Based Transcriptome Analysis Of The Interaction Between Perrenial Ryegrass (Lolium Perenne) And The Fungal Endophyte Neotyphodium Lolii, S. Felitti, P. Tian, T. Webster, D. Edwards, G. C. Spangenberg
Microarray-Based Transcriptome Analysis Of The Interaction Between Perrenial Ryegrass (Lolium Perenne) And The Fungal Endophyte Neotyphodium Lolii, S. Felitti, P. Tian, T. Webster, D. Edwards, G. C. Spangenberg
IGC Proceedings (1997-2023)
Neotyphodium lolii, Neotyphodium coenophialum and Epichloë festucae are common symbiotic fungal endophytes of the temperate pasture grasses perennial ryegrass (Lolium perenne), tall fescue (Festuca arundinacea) and red fescue (Festuca rubra), respectively. A genomic resource of 13,964 expressed sequence tags (ESTs), representing 7,585 unique endophyte genes, has been established for Neotyphodium and Epichloë fungal endophytes.
A High-Throughput Gene Silencing Approach For Studying The Interaction Between Perennial Ryegrass (Lolium Perenne) And The Fungal Endophyte Neotyphodium Lolii, S. Felitti, P. Tian, D. Edwards, G. C. Spangenberg
A High-Throughput Gene Silencing Approach For Studying The Interaction Between Perennial Ryegrass (Lolium Perenne) And The Fungal Endophyte Neotyphodium Lolii, S. Felitti, P. Tian, D. Edwards, G. C. Spangenberg
IGC Proceedings (1997-2023)
Perennial ryegrass (Lolium perenne L.) and its fungal endophyte (Neotyphodium lolii) are known to establish a mutualistic association that impacts on the agronomic productivity of endophyte-infected ryegrass pastures. To study this interaction at the molecular level, a genomic resource consisting of 13,964 endophyte ESTs has been generated. However, the functions of a large proportion of these genes remain to be elucidated. Recent work has demonstrated the potential for RNA-mediated gene silencing to suppress gene expression in a sequence specific manner thus allowing for the subsequent analysis of gene function.
Metabolome Analysis Of The Interaction Between Perennial Ryegrass (Lolium Perenne) And The Fungal Endophyte Neotyphodium Lolii, P. Tian, S. Felitti, M. P. Dobrowolski, K. F. Smith, D. Edwards, R. Hall, J. Kopka, G. C. Spangenberg
Metabolome Analysis Of The Interaction Between Perennial Ryegrass (Lolium Perenne) And The Fungal Endophyte Neotyphodium Lolii, P. Tian, S. Felitti, M. P. Dobrowolski, K. F. Smith, D. Edwards, R. Hall, J. Kopka, G. C. Spangenberg
IGC Proceedings (1997-2023)
Perennial ryegrass (Lolium perenne L.) and tall fescue (Festuca arundinacea Schreb.) frequently contain endophytic fungi (Neotyphodium lolii in perennial ryegrass and N. coenophialum in tall fescue). The presence of the endophyte has been shown to improve seedling vigour, persistence and drought tolerance in marginal environments as well as provide protection against some insect pests. Endophyte-infected grasses also produce a wide range of metabolites, including ergopeptine alkaloids, indole-isoprenoid lolitrems, pyrrolizidine alkaloids, and pyrrolopyrazine alkaloids. In contrast to information on alkaloids and animal toxicosis, the beneficial physiological aspects of the endophyte/grass interactions have not been well characterised. The physiological …
Gene Discovery And Molecular Dissection Of Fructan Metabolism In Perennial Ryegrass (Lolium Perenne), J. Chalmers, A. Lidgett, X. Johnson, K. Terdich, N. Cummings, Y. Y. Cao, K. Fulgueras, M. Emmerling, T. Sawbridge, E. K. Ong, A. Mouradov, G. C. Spangenberg
Gene Discovery And Molecular Dissection Of Fructan Metabolism In Perennial Ryegrass (Lolium Perenne), J. Chalmers, A. Lidgett, X. Johnson, K. Terdich, N. Cummings, Y. Y. Cao, K. Fulgueras, M. Emmerling, T. Sawbridge, E. K. Ong, A. Mouradov, G. C. Spangenberg
IGC Proceedings (1997-2023)
Fructans are the main soluble carbohydrate stored in up to a third of the vegetation of the earth, including the economically important temperate grasses. Fructans are polymers of fructose attached to a sucrose precursor. Perennial ryegrass (L. perenne L.) accumulates fructans of the inulin series, inulin neoseries and levan neoseries. Four enzymes are required to produce fructans of this profile: 1-SST (sucrose:sucrose 1- fructosyltransferase), 1-FFT (fructan:fructan 1-fructosyltransferase), 6G-FFT (6-glucose fructosyltransferase) and 6-FFT (fructan:fructan 6-fructosyltransferase) or 6-SFT (sucrose:fructan 6-fructosyltransferase) (Figure 1). Fructan biosynthetic enzymes have evolved from invertases and thus it is argued that fructan metabolism is an extension …
The Investigation Of Flowering Control In Late/Rare Flowering Lolium Perenne, S. Byrne, I. S. Donnison, L. J. Mur, E. Guiney
The Investigation Of Flowering Control In Late/Rare Flowering Lolium Perenne, S. Byrne, I. S. Donnison, L. J. Mur, E. Guiney
IGC Proceedings (1997-2023)
Flowering in Lolium perenne (perennial ryegrass) results in reduced digestibility and its inhibition would enhance forage quality. Flowering regulation has been well studied in Arabidopsis thaliana (Simpson and Dean, 2002) and orthologs of Arabidopsis flowering genes underlying heading date Quantitative Trait Loci (QTL) have been identified in rice (Yano, M et al., 2000). However it is not clear yet how universally applicable such studies are to Lolium. The project goals are to characterise the gene expression profiles of late/rare flowering L. perenne plants to determine factors affecting flowering and to map the genes involved in the flowering process. Initial …
Application Of Molecular Markers In Genetic Resources Management Of Perennial Ryegrass, R. Van Treuren
Application Of Molecular Markers In Genetic Resources Management Of Perennial Ryegrass, R. Van Treuren
IGC Proceedings (1997-2023)
Key points
- Molecular markers are effective tools to support traditional approaches in plant genetic resources management.
- 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.
- No specific conservation measures were recommended to maintain the genetic diversity of perennial ryegrass occurring in traditional Dutch grasslands.
- 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 …
In Situ Rumen Degradability Of Perennial Ryegrass Cultivars Differing In Ploidy And Heading Date In Ireland, V. Olsson, J. J. Murphy, F. P. O'Mara, M. O'Donovan, F. J. Mulligan
In Situ Rumen Degradability Of Perennial Ryegrass Cultivars Differing In Ploidy And Heading Date In Ireland, V. Olsson, J. J. Murphy, F. P. O'Mara, M. O'Donovan, F. J. Mulligan
IGC Proceedings (1997-2023)
Grazed grass is the predominant feed in Irish dairy and beef cattle production systems. Knowledge of the degradability characteristics of protein in Irish forages is necessary for the establishment of protein values (PDIE and PDIN values) for these. This knowledge would also facilitate more accurate formulation of supplements for grass diets with the potential to reduce nitrogen (N) excretion.
Survey Of Tetraploid And Diploid Perennial Pastures In The Waikato For Number Of Spores Produced By The Fungus Pithomyces Chartarum, J. P. J. Eerens, W. W. Nichol, J. Waller, J. M. Mellsop, M. R. Trolove, M. G. Norriss
Survey Of Tetraploid And Diploid Perennial Pastures In The Waikato For Number Of Spores Produced By The Fungus Pithomyces Chartarum, J. P. J. Eerens, W. W. Nichol, J. Waller, J. M. Mellsop, M. R. Trolove, M. G. Norriss
IGC Proceedings (1997-2023)
Facial eczema (FE) is a disease of livestock, caused by a toxin released into the bloodstream after digestion of spores of Pithomyces chartarum, a fungus residing in necrotic plant material in the base of pastures (di Menna & Bailey, 1973). Spore numbers tend to be highest in warm, humid conditions, where high post grazing residuals have lead to a build up of necrotic plant material. Tetraploid perennial ryegrass pastures tend to be more palatable, and with lower post gazing residuals, than equivalent diploid pastures; thus we hypothesised that spore numbers would be lower in tetraploid pastures. A survey of …
Perennial Ryegrass Variety Differences In Nutritive Value Characteristics, T. J. Gilliland, R. E. Agnew, A. M. Fearson, F. E. A. Wilson
Perennial Ryegrass Variety Differences In Nutritive Value Characteristics, T. J. Gilliland, R. E. Agnew, A. M. Fearson, F. E. A. Wilson
IGC Proceedings (1997-2023)
Animal grazing performance at grass is predominately determined by herbage intake rates, with high yielding dairy cows requiring up to 20 kg/d DM within a limited grazing time (Gibb, 1998). Grass nutritional factors such as seasonal patterns in digestibility and water-soluble carbohydrate levels have been linked to animal productivity (Davies et al., 1991), while sward surface height, herbage mass, bulk density and green leaf mass have been shown to promote high grazing intake (Barrett et al., 2001). Furthermore, fatty acid profiles have been shown to improve the unsaturated fatty acid composition of milk, with potential human health benefits …