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Articles 1 - 18 of 18
Full-Text Articles in Physical Sciences and Mathematics
Effect Of Timing And Intensity Of Drought On Perennial Ryegrass Seed Yield, R. J. Martin, R. N. Gillespie, S. Maley
Effect Of Timing And Intensity Of Drought On Perennial Ryegrass Seed Yield, R. J. Martin, R. N. Gillespie, S. Maley
IGC Proceedings (1997-2023)
Perennial ryegrass seed worth about $50 million is produced annually in Canterbury, New Zealand (Rowarth 1998). Ryegrass seed production in New Zealand is often affected by drought, reducing both seed number and seed size (Rolston et al., 1994). Irrigation management recommendations are not currently available for farmers growing ryegrass seed crops. To quantify the effect of water stress on perennial ryegrass seed yield, we carried out an experiment in a rainshelter where rainfall was excluded from experimental plots otherwise exposed to normal weather (Martin et al., 1990).
Using Abandoned Paddy Fields For Grazing In Northern Japan, M. Nashiki, H. Narita, Y. Higashiyama
Using Abandoned Paddy Fields For Grazing In Northern Japan, M. Nashiki, H. Narita, Y. Higashiyama
IGC Proceedings (1997-2023)
The number of abandoned paddy fields is increasing in Japan, because the government has been regulating rice production. It has been recommended that the abandoned paddy fields be used for stock raising. However, there is sometimes a lack of information about the land on the abandoned paddy fields and farmers want to know the cost of fencing and the best grass species to use. This paper seeks to provide farmers with information on how to begin to use the abandoned paddy fields as pastures in hilly rural areas in Japan.
Selection For Tillering In Lolium Multiflorum L. In Texas Usa, L. R. Nelson, G. W. Evers, M. J. Parsons
Selection For Tillering In Lolium Multiflorum L. In Texas Usa, L. R. Nelson, G. W. Evers, M. J. Parsons
IGC Proceedings (1997-2023)
Annual ryegrass is an important cool season forage in Texas and across the southern USA with approximately 2 million ha planted annually. Early tillering will enhance the leaf area index and the amount of photosynthesis which will improve seedling vigor and early forage production. The objective of this study was to determine if it was possible to select for early tiller (shoot) production in a diploid and tetraploid annual ryegrass breeding population. We expect early tiller production would be correlated with improved early season forage production with annual ryegrass.
Ensiling Characteristics And Ruminal Degradation Of Italian Ryegrass With Or Without Wilting And Added Cell Wall Degrading Enzymes, Z. Yu, Jianguo Han, Z. He, X. Qingfang, B. Chunsheng, N. Nishino
Ensiling Characteristics And Ruminal Degradation Of Italian Ryegrass With Or Without Wilting And Added Cell Wall Degrading Enzymes, Z. Yu, Jianguo Han, Z. He, X. Qingfang, B. Chunsheng, N. Nishino
IGC Proceedings (1997-2023)
The previous experiment (Yu zhu et al.,1999) has shown that the efficacy of added enzymes varied greatly according to the DM content of the material crop. The silage DM did not alter the effects of enzymes on the in vitro digestion of NDF (Yu zhu et al.,1999, Yu zhu et al.,2000). The aim of this experiment was to study the effect of wilting and enzymes on fermentation quality, chemical composition and in situ digestion of Italian ryegrass (Lolium multiflorum Lam.) silage.
Use Of Green Sulla Forage For Feeding. 1. Effects On Lamb Growth And Gastrointestinal Nematode Parasite Infestation, D. Giambalvo, A. Di Grigoli, M. L. Alicata, B. Formoso, A. S. Frenda, P. Trapani
Use Of Green Sulla Forage For Feeding. 1. Effects On Lamb Growth And Gastrointestinal Nematode Parasite Infestation, D. Giambalvo, A. Di Grigoli, M. L. Alicata, B. Formoso, A. S. Frenda, P. Trapani
IGC Proceedings (1997-2023)
Recent studies have shown that some forage legumes containing condensed tannins (CT), such as sulla (Hedysarum coronarium L.), can reduce the gastrointestinal nematode burden in sheep (Niezen et al., 1998) and increase post-ruminal protein availability (Waghorn et al., 1994). This study aimed to evaluate the anthelmintic and nutritional properties of sulla forage in relation to its CT content. Thus, the growth performance and the level of nematode infestation of lambs fed sulla were compared with those of lambs fed ryegrass (Lolium multiflorum Lam. subsp. wersterwoldicum), lacking in CT.
Effects Of Simulated High-Sugar Forages On Grazing Behaviour Of Sheep, Gerald P. Cosgrove, A. J. Parsons
Effects Of Simulated High-Sugar Forages On Grazing Behaviour Of Sheep, Gerald P. Cosgrove, A. J. Parsons
IGC Proceedings (1997-2023)
Sustaining an optimum composition in mixed-species pasture and in the diet of grazing animals is constrained by many factors. Altering the concentration of water soluble carbohydrate (WSC) of one species to improve its nutritional value for animals may not deliver the benefits in the assumed manner if it also affects preference and the balance of species in the pasture. Furthermore, associated changes in other constituents (e.g. fibre, protein) make it difficult to attribute animal responses solely to the manipulated trait (e.g. Lee et al. 2000). The objective of this study was to simulate changes in the concentration of water soluble …
The Evaluation Of Kikuyu Oversown With Ryegrass And Clover In Terms Of Milk Production, Robin Meeske, Philip R. Botha, Hennie A. Snyman
The Evaluation Of Kikuyu Oversown With Ryegrass And Clover In Terms Of Milk Production, Robin Meeske, Philip R. Botha, Hennie A. Snyman
IGC Proceedings (1997-2023)
Kikuyu (Pennisetum clandestinum) comprises the greater part of irrigated summer and autumn pasturage for milk production in the Southern Cape. Milk production per cow is limited by low forage quality. The aim of the study was to determine the milk production from kikuyu (K), kikuyu oversown with annual ryegrass (Lolium multiflorum spp. cv Energa) (KR), kikuyu oversown with a mixture of perennial ryegrass (Lolium perenne cv Yatsyn, Dobson) and perennial white clover (Trifolium repens cv Haifa, Waverley) and red clover (Trifolium pratense cv Kenland, Cherokee) (KRC) and kikuyu oversown with a mixture of perennial …
Liveweight Gain Of Lambs Grazing Six Short-Term Ryegrass Cultivars, W. W. Nichol, M. G. Norriss
Liveweight Gain Of Lambs Grazing Six Short-Term Ryegrass Cultivars, W. W. Nichol, M. G. Norriss
IGC Proceedings (1997-2023)
Increasing dry matter (DM) production per ha is a key goal in ryegrass (Lolium) breeding programmes (Easton et al., 2002), based on the assumption that increased DM yield will in turn increase profitability per ha, through an increase in animal productivity. However, the performance of animals grazing pasture can also be modified by the quality of the forage on offer, and the presence of toxins within the pasture. The objective of this study was to compare the liveweight gain per hectare of lambs grazing six short-term ryegrasses, which had been selected for various combinations of improved DM …
Analysis Of Genetic Changes In Single-Variety Ryegrass Swards, C. Straub, G. Boutet, Christian Huyghe
Analysis Of Genetic Changes In Single-Variety Ryegrass Swards, C. Straub, G. Boutet, Christian Huyghe
IGC Proceedings (1997-2023)
Ryegrass varieties are synthetics, with a wide within-variety genetic variance for most traits. Ryegrass swards are likely to experience genetic changes with seasons and years because of plant death, asymmetric vegetative reproduction or plant recruitment through reproduction or seed immigration. These changes may be related to or induce changes in agronomic traits, such as biomass production or dry matter composition. The present research was undertaken to measure genetic changes in swards obtained from sowings of a single variety of ryegrass. These changes were evaluated using both neutral molecular markers and morphological traits. The present paper deals with the molecular markers.
Efficient In Vitro Regeneration System From Seed Derived Callus Of Perennial Ryegrass (Lolium Perenne) And Annual Ryegrass (Lolium Multiflorum), S. Chennareddy, R. V. Sairam, S. L. Goldman
Efficient In Vitro Regeneration System From Seed Derived Callus Of Perennial Ryegrass (Lolium Perenne) And Annual Ryegrass (Lolium Multiflorum), S. Chennareddy, R. V. Sairam, S. L. Goldman
IGC Proceedings (1997-2023)
The commercially important ryegrasses in cool temperate climates throughout the world are annual ryegrass (Lolium multiflorum L.) and perennial ryegrass (Lolium perenne L). Improvements through conventional breeding have been slow as they are usually heterozygous and highly self-infertile. Hence, there is a need to use modern biotechnological tools to the development of improved rye grass cultivars for incorporating value added traits. Successful transformation of rye grasses has been done using suspension cells, which is time consuming and laborious (Spangenberg et al., 1995, 1998). We report here a rapid and highly efficient in vitro plant regeneration system from …
Identification Of Quantitative Trait Loci For Flowering Time In A Field-Grown Lolium Perene X Lolium Multiflorum Mapping Population, R. N. Brown, R. E. Barker, S. E. Warnke, L. A. Brilman, M. A. R. Mian, S. C. Sim, G. Jung
Identification Of Quantitative Trait Loci For Flowering Time In A Field-Grown Lolium Perene X Lolium Multiflorum Mapping Population, R. N. Brown, R. E. Barker, S. E. Warnke, L. A. Brilman, M. A. R. Mian, S. C. Sim, G. Jung
IGC Proceedings (1997-2023)
Perennial ryegrass (L. perenne) and annual, or Italian, ryegrass (L. multiflorum) are considered to be separate species by the seed trade, and are used and bred for distinct purposes. However, the two species are cross-fertile. Seed producers rely on the different flowering times of the two species to produce pure seed. Flowering times can overlap, leading to genetic mixing. Contamination of perennial ryegrass seed lots with annual types is an expensive problem for grass seed producers in western Oregon, USA.
Quantitative Trait Loci For Vegetative Traits In Perennial Ryegrass (Lolium Perenne L.), A. M. Sartie, H. S. Easton, Marty J. Faville, C. Matthew
Quantitative Trait Loci For Vegetative Traits In Perennial Ryegrass (Lolium Perenne L.), A. M. Sartie, H. S. Easton, Marty J. Faville, C. Matthew
IGC Proceedings (1997-2023)
Physiological (EP) research in forage grasses relates traits such as leaf elongation rate (LER), leaf elongation duration (LED), and leaf appearance interval (ALf), to forage yield (Chapman & Lemaire, 1993). This paper reveals preliminary quantitative trait locus (QTL) discovery for eight EP traits in perennial ryegrass. It also investigates the potential role of multivariate analyses such as principal component analysis (PCA) in QTL analysis of EP data.
Development And Field Evaluation Of Transgenic Ryegrass (Lolium Spp.) With Down-Regulation Of Main Pollen Allergens, N. Petrovska, A. Mouradov, Z. Y. Wang, K. F. Smith, G. C. Spangenberg
Development And Field Evaluation Of Transgenic Ryegrass (Lolium Spp.) With Down-Regulation Of Main Pollen Allergens, N. Petrovska, A. Mouradov, Z. Y. Wang, K. F. Smith, G. C. Spangenberg
IGC Proceedings (1997-2023)
Ryegrass (Lolium spp.) pollen is a widespread source of airborne allergens and is a major cause of hayfever and seasonal allergic asthma, which affect approximately 25% of the population in cool temperate climates. The main allergens of ryegrass pollen are the proteins Lol p 1 and Lol p 2. These proteins belong to two major classes of grass pollen allergens to which over 90% of pollen-allergic patients are sensitive. The functional role in planta of these pollen allergen proteins remains largely unknown. The generation, analysis and field evaluation of transgenic plants with reduced levels of the main ryegrass pollen allergens, …
An In Silico Dna Sequence Comparison Of The Perennial Ryegrass And Rice Genomes, Marty J. Faville
An In Silico Dna Sequence Comparison Of The Perennial Ryegrass And Rice Genomes, Marty J. Faville
IGC Proceedings (1997-2023)
Comparative mapping studies in the family Poaceae, which includes rice (a model species for this family) and perennial ryegrass (PRG) have indicated macro-colinearity of genes is generally conserved across different genomes. Genome mapping of simple sequence repeat markers derived from expressed sequence tags (EST-SSRs) for PRG (Faville et al., 2004) provides a vehicle for DNA sequence-based matching of mapped PRG genes to orthologous positions in the rice genome, which can be used to establish comparative relationships between these species’ genomes. We have initiated such an analysis using an EST-SSR-based PRG genome map. Our objective was to assess this in …
The Seasonal Botanical Composition, Calcium And Phosphorus Content Of Kikuyu Oversown With Ryegrass And Clover, Philip R. Botha, Robin Meeske, Hennie A. Snyman
The Seasonal Botanical Composition, Calcium And Phosphorus Content Of Kikuyu Oversown With Ryegrass And Clover, Philip R. Botha, Robin Meeske, Hennie A. Snyman
IGC Proceedings (1997-2023)
Kikuyu (Pennisetum clandestinum) is one of the major grasses used for summer and autumn grazing in the Southern Cape coast area of South Africa. Annual ryegrass (Lolium multiflorum spp.), perennial white (Trifolium repens) and red clover (Trifolium pratense) can be incorporated into an existing kikuyu stand to improve pasture quality and spring production. The aim of this study was to determine the persistence of these species and effects on the calcium and phosphorus content of kikuyu (K), kikuyu oversown with annual ryegrass (KR), kikuyu oversown with a mixture of perennial ryegrass (L. …
The Effect Of Harvest Management On Forage Production And Self-Reseeding Potential Of Italian Ryegrass (Lolium Multiflorum L.), P. W. Bartholomew, R. D. Williams
The Effect Of Harvest Management On Forage Production And Self-Reseeding Potential Of Italian Ryegrass (Lolium Multiflorum L.), P. W. Bartholomew, R. D. Williams
IGC Proceedings (1997-2023)
Italian ryegrass (Lolium multiflorum L.) (IRG) can be managed to produce a seed output sufficient for effective re-establishment, without compromising forage yield, it may provide an alternative to perennial cool-season grasses in the Southern Great Plains of the U.S.A. The reduction in cost of replanting and avoidance of cultivation offered by a self-seeding crop may be particularly useful in low-input production systems. We examined the effect of dates of initial harvest in spring and of partial harvests on forage yield, seed output and re-establishment of Italian ryegrass.
Effect Of Nitrogen On The Radiation Use Efficiency For Modelling Grass Growth, R. Lambert, A. Peeters
Effect Of Nitrogen On The Radiation Use Efficiency For Modelling Grass Growth, R. Lambert, A. Peeters
IGC Proceedings (1997-2023)
When nitrogen (N) is not at a sufficient level to permit maximum growth rate, dry matter production is reduced. Models of plant growth in relation to solar radiation intercepted by the crop have been largely used. According to these models, N deficiency can act on the leaf extension and thus on the quantity of radiation intercepted by the crop, but also by reducing the radiation use efficiency of the crop (RUE) (Bélanger, 1990). The effect of N on the RUE of ryegrass swards is determined and discussed.
Radiation Use Efficiency Of Ryegrass: Determination With Non Cumulative Data, R. Lambert, A. Peeters
Radiation Use Efficiency Of Ryegrass: Determination With Non Cumulative Data, R. Lambert, A. Peeters
IGC Proceedings (1997-2023)
The growth of a crop is generally described as biomass accumulation per unit time. Monteith (1977) developed a model of growth where biomass accumulation is related to solar radiation intercepted by the crop. This model has been largely used for different crops. The conversion factor between radiation absorbed or intercepted by the crop and the biomass production is called “radiation use efficiency” or “dry matter radiation quotient”. Radiation use efficiency (RUE) is usually calculated as the regression coefficient of the linear relationship between crop biomass measured repeatedly during growth and cumulated intercepted or absorbed solar radiation. Demetriades-Shah et al. …