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Full-Text Articles in Physical Sciences and Mathematics

An Overview Of The Physiology And Biochemistry Of N Reserves Mobilization In Forage Species, F Le Dily, A Ourry, J Boucaud Apr 2024

An Overview Of The Physiology And Biochemistry Of N Reserves Mobilization In Forage Species, F Le Dily, A Ourry, J Boucaud

IGC Proceedings (1997-2023)

Recent works focusing on the physiological and biochemical events associated to perennial forages sustainability (re-growth after defoliation, winter survival), provided evidence that vegetative storage proteins (VSPs, ca proteins stored in remaining organs and specifically mobilized) were key organic compounds for shoot regrowth. Attempts to elucidate environmental conditions involved in VSPs deposit ability of different species are under progress today. In contrast, mechanisms of spring- or cut-induced proteolysis are investigated at a lesser extend. This contribution is an opportunity to summarize our knowledge of N-reserves mobilization and to set the question of VSPs breakdown regulation.


Intraspecific Competition In Lucerne And Relationships With Reserve Availability, Jean Christophe Avice, Alain Ourry, Gilles Lemaire, Jeffrey J. Volenec, Jean Boucaud Apr 2024

Intraspecific Competition In Lucerne And Relationships With Reserve Availability, Jean Christophe Avice, Alain Ourry, Gilles Lemaire, Jeffrey J. Volenec, Jean Boucaud

IGC Proceedings (1997-2023)

Below-ground reserves are thought to provide an indication of a forage potential for shoot regrowth after defoliation. The aim of this work was to re-evaluate the causal relationships existing between organic reserves (non-structural carbohydrates and N reserves) and shoot regrowth of alfalfa. The variations brought about by cultivar differences (cv Lodi or Europe), length of the previous regrowth period (30 or 45 d), or by intraspecific competition for light within a dense canopy, were studied. Field grown plants were harvested at weekly intervals, and separated as dominant, intermediate and suppressed plants. Shoot regrowth yield was determined and taproot were analyzed …


Effects Of Nitrogen On The Growth Of Hyparrhenia Diplandra, J Nkandza Apr 2024

Effects Of Nitrogen On The Growth Of Hyparrhenia Diplandra, J Nkandza

IGC Proceedings (1997-2023)

The nitrogen effects on Hyparrhenia diplandra were studied. Plants were grown on nutrient solutions of variable concentrations in nitrogen. The supplied nitrogen increased tillering, leaf production, lamina area, total dry matter accumulation and total nitrogen accumulation in lamina. A detailed examination showed that the effect on tillering was the main cause of the differences observed in dry weights between different treatments. The nitrogen supply elongated significantly the lamina and nitrogen deficiency increased its thickness; but this was not enough to compensate the loss of weight in lower nitrogen treatment. The lamina area as well as nitrogen accumulation in the lamina …


Nitrogen Use Efficiency Of Timothy Populations, G Belanger, C Murray, R Michaud, F Gastal, J E. Richards Apr 2024

Nitrogen Use Efficiency Of Timothy Populations, G Belanger, C Murray, R Michaud, F Gastal, J E. Richards

IGC Proceedings (1997-2023)

The objective of this study was to determine the variability in N use efficiency among field-grown timothy (Phelum pratense L.) populations. Shoot biomass and N uptake were measured at the end of the spring growth cycle on six timothy populations fertilized with three N rates at two sites in Eastern Canada. The variability in shoot biomass among populations was similar under limiting and nonlimiting N conditions. The ranking of the populations, however, differed under limiting and non-limiting N conditions, and also between the two sites under limiting N conditions. The differences in shoot biomass among populations under highly N …


Tree Forages As Nitrogen Source For Ruminants In Sahelian Agro-Silvipastoral Systems, S T. Fall, B M. Doreau Mar 2024

Tree Forages As Nitrogen Source For Ruminants In Sahelian Agro-Silvipastoral Systems, S T. Fall, B M. Doreau

IGC Proceedings (1997-2023)

Tree forages contribute up to 80% DM and 100% nitrogen content in the ruminants diet in the Sahel during the dry season. However, crude protein (CP) concentration in browse within a wide range and variation factors remain to be elucidated for better integration of browses in ruminants feeding systems. Variation factors of CP content and in vivo digestibility of four Sahelian browse species were investigated to appreciate the potential as nitrogen sources in Sahelian ruminant feeding systems. Seasonal variations in nitrogen content were evaluated in different plants part of A. raddiana, B. rufescens, B. aegyptiaca and G. senegalensis harvested in …


The Effects Of Tree Density On Pasture Production Under Acacia Melanoxylon, B S. Thorrold, I L. Power, M B. Dodd Mar 2024

The Effects Of Tree Density On Pasture Production Under Acacia Melanoxylon, B S. Thorrold, I L. Power, M B. Dodd

IGC Proceedings (1997-2023)

Silvi-pastoral systems could contribute to greater total productivity and more sustainable land management of grazed pastures in New Zealand. Despite this potential, little is known of the interactions of tree species and environment on pasture growth. In this paper we report the effects of tree density on pasture yield in an Acacia melanoxylon silvi-pastoral system. The results show decreasing pasture yield with increasing tree density, although the extent of the reduction is less than would be expected under Pinus radiata. Results suggest that shade is the dominant factor causing yield decline in this study, while reduced N availability is …


Research Programme To Improve The Utilization Of Home-Grown Forages In The Netherlands, A.M. Van Vuuren, A H. Bosma, G J. Kaspers, J.J. M.H. Ketelaars, E.N. Van Loo, H J.P. Marvin, H Valk, G.W.J. Van De Ven Feb 2024

Research Programme To Improve The Utilization Of Home-Grown Forages In The Netherlands, A.M. Van Vuuren, A H. Bosma, G J. Kaspers, J.J. M.H. Ketelaars, E.N. Van Loo, H J.P. Marvin, H Valk, G.W.J. Van De Ven

IGC Proceedings (1997-2023)

In The Netherlands a research programme has been initiated by the Ministry of Agriculture, Nature Management and Fisheries to increase the proportion of high-quality home-grown forage in rations for dairy cows. This should result in a more sustainable dairy husbandry by improving the efficiency of utilization of nitrogen and phosphorus from home-grown forages (mainly grass and maize) on farm level. Research disciplines involved are plant breeding, forage harvesting and conservation and nutrition.


Comparison Of Two Low-Input Cow/Calf Production Systems On Temperate Grassland, W. B. Bryan, Mata Padrino, E. Felton, E. C. Prigge, V. W. Temu, O. J. Gekara Feb 2024

Comparison Of Two Low-Input Cow/Calf Production Systems On Temperate Grassland, W. B. Bryan, Mata Padrino, E. Felton, E. C. Prigge, V. W. Temu, O. J. Gekara

IGC Proceedings (1997-2023)

Two systems of grass farming were compared in an eight-year experiment in West Virginia, USA. The grassland consisted primarily of cocksfoot (Dactylis glomerara L.), Kentucky bluegrass (Poa pratensis L.), tall fescue (Festuca arundinacea Schreb.), and red (Trifolium pretense L.) and white clover (T. repens L.). The objective was to compare two systems of beef cow calf production. The experiment was a randomized complete block with two replicated treatments. The grassland of treatment 1 (system 1) was overseeded with legumes, grazing started 1 wk earlier and continued 1 wk later than treatment 2 (system 2) and …


A Novel Technique To Label Cover Crop Biomass Using Stable Isotopes, L. M. D. Queiroz, José C. B. Dubeux Jr., Lynn E. Sollenberger, M. Wallau, D. R. S. Loures, M. A. Bernardini, I. L. Bretas, S. F. Novo, K. R. Trumpp, K. T. Oduor, J. D. Pereira Neto, M. Ruiz-Moreno Feb 2024

A Novel Technique To Label Cover Crop Biomass Using Stable Isotopes, L. M. D. Queiroz, José C. B. Dubeux Jr., Lynn E. Sollenberger, M. Wallau, D. R. S. Loures, M. A. Bernardini, I. L. Bretas, S. F. Novo, K. R. Trumpp, K. T. Oduor, J. D. Pereira Neto, M. Ruiz-Moreno

IGC Proceedings (1997-2023)

Stable isotopes can be used as tracers for carbon and nitrogen pathways being a great tool to track nutrients in integrated systems. The objective of this experiment was to understand the partitioning of 15N and 13C within cover crop plants when they were labeled with stable isotopes, using chambers under field conditions. Cover crops were planted at the University of Florida, North Florida Research and Education Center-Marianna, located in Marianna, FL. Treatments were four cover crops, in which one was considered a typical cover crop system and the other three consisted of an integrated crop-livestock system with or without the …


Towards Sociobiogeochemistry: Critical Perspectives On Anthropogenic Alterations To Soil Nitrogen Chemistry Via U.S. Urban And Suburban Development, Christopher D. Ryan Feb 2024

Towards Sociobiogeochemistry: Critical Perspectives On Anthropogenic Alterations To Soil Nitrogen Chemistry Via U.S. Urban And Suburban Development, Christopher D. Ryan

Dissertations, Theses, and Capstone Projects

The ecological impacts of changes to land use are relevant to concerns about climate change, eutrophication of waterbodies, and reductions in biodiversity. As a foundational component of ecosystem functioning, changes to soil biogeochemistry have significant effects on overall ecosystem health. With cities continuing to grow and develop in extent, the impacts of urbanization and suburbanization on soils are of particular concern. Despite a wide range of natural climatic and geologic conditions, several factors have driven similar patterns of land transformation and management across the United States. In particular, federal initiatives including the Home Owners Loan Corporation, the Federal Housing Administration, …


Herbage Accumulation And Mass In Massai Grass Plots Mixed With Forage Peanut And Fertilized With Nitrogen, Carlos A. B. Carvalho, M. O. Leal Junior, P. P. Carneiro, J. V. B. Ramos, N. Schultz, J. C. C. Almeida, A. J. Paiva Jan 2024

Herbage Accumulation And Mass In Massai Grass Plots Mixed With Forage Peanut And Fertilized With Nitrogen, Carlos A. B. Carvalho, M. O. Leal Junior, P. P. Carneiro, J. V. B. Ramos, N. Schultz, J. C. C. Almeida, A. J. Paiva

IGC Proceedings (1997-2023)

The objective of this work was to evaluate herbage accumulation and mass during the growing season of Massai grass mixed with peanut forage and fertilized with nitrogen. The work was carried out at Federal Rural University of Rio de Janeiro, Brazil, from 11/2021 to 03/2022. A randomized block experimental design was used, in plots of Massai grass Megathyrsus maximus, in a factorial arrangement, with seven replications. Four treatments formed by the combination of the presence or absence of Archis pintoi and nitrogen fertilization (0 and 50 kg ha-1 of N). Canopy heights of the plots were evaluated weekly …


Application Of Fall Nitrogen Increased Spring Tall Fescue Yield, B. L. Hendrix, Christopher D. Teutsch, J. Duckworth Jan 2024

Application Of Fall Nitrogen Increased Spring Tall Fescue Yield, B. L. Hendrix, Christopher D. Teutsch, J. Duckworth

IGC Proceedings (1997-2023)

Late season nitrogen fertilization is a practice that has long been implemented in turfgrass production. This practice involves applying nitrogen from September through December and results in an extended green period in the fall without stimulating excessive shoot growth. The longer green period results in higher levels of carbohydrate reserves and enhanced root growth compared with a spring-summer fertilization program. In addition to these benefits, sods fertilized in late fall have been shown to green up two to six weeks earlier in the spring. Limited research has considered the impact of late fall nitrogen applications on grass growth in hayfields …


Chlorophyll And Mineral Dynamics Of Perennial Grass Species Found In Semi- Arid Rangelands Of South Africa, N. H. Msiza, K. E. Ravhuhali, H. K. Mokoboki, Sydney Mavengahama, L. E. Motsei Jan 2024

Chlorophyll And Mineral Dynamics Of Perennial Grass Species Found In Semi- Arid Rangelands Of South Africa, N. H. Msiza, K. E. Ravhuhali, H. K. Mokoboki, Sydney Mavengahama, L. E. Motsei

IGC Proceedings (1997-2023)

Minerals are essential for ruminants and are mostly provided by grass species. Their growth stage is vital in the supply of these minerals. Perennial grass species have been mostly undervalued, owing to the scarce information concerning their potential feeding value and little documentation about their potential nutritive value in different growth stages. This study was conducted to investigate the chlorophyll and mineral concentration of grass species at different growth stages under greenhouse conditions at the North-West University Experimental farm, North West province, South Africa. The soil, collected from different villages, was mixed and samples were drawn for chemical analysis before …