Physical Sciences and Mathematics Commons^™

Legume-Rhizobia Relationship In The Nitrogen Fixation Of A New Mediterranean Pasture Legume (Biserrula Pelecinus L.), A Loi, J G. Howieson, P S. Cocks, S J. Carr

IGC Proceedings (1997-2023)

Biserrula pelecinus (biserrula) is a pasture legume of Mediterranean climates. Because of its ability to survive on acidic and infertile soils, it has been introduced to southern Australia as a potential alternative or companion plant to serradella and subterranean clover. The successful introduction of this species will be reliant upon the selection of an appropriate inoculant strain of its root-nodule bacteria and understanding of its ecology. A selection of five rhizobial strains isolated from biserrula nodules collected in Sardinia and Greece were examined for their ability to nodulate and fix nitrogen with 3 genotypes of biserrula. Although all rhizobial strains …

New Insights For Benefit Of Legume Inclusion In Grazing Systems, David M. Jaramillo, José C. B. Dubeux Jr., L. M. D. Queiroz, L. Garcia

IGC Proceedings (1997-2023)

The benefits and challenges of legume inclusion in grazing systems have been well documented over time and across different regions. Recent investigations have provided novel insights into the benefits of legume inclusion in grazing systems. Our objective is not to provide a wide overview of the benefits of legume inclusion but to explore novel insights of recent advancements made from studies evaluating legume inclusion in grazing systems. Efficiency of resource use through legume inclusion in grazing systems can reduce the water footprint associated with beef production through improvements in forage nutritive value and animal performance. These efficiencies also translate into …

Climate Change And Legume Performance In Grassland Agroecosystems, Lynn E. Sollenberger, M. M. Kohmann

IGC Proceedings (1997-2023)

We reviewed the literature to assess the effect of climate change factors on forage legumes. Whether growing in monoculture or mixtures with grasses, exposing legumes to elevated CO₂ (eCO₂) generally leads to sustained increases in forage accumulation (FA) and N fixation, but elevated temperature (eT) in conjunction with eCO₂ usually reduces magnitude of these responses. In legumes, nodules represent large C sinks, precluding photosynthetic acclimation to eCO₂ observed in non-N fixing plants. Greater N fixation in legume-grass mixtures exposed to eCO₂ is due to greater percentage of legume N derived from symbiotic fixation and …

Plant Arrangement Effects On Dry Matter Production And Nitrogen Fixation Of Berseem Clover: Annual Ryegrass Mixture, C. Attardo, G. Di Miceli, A. S. Frenda, D. Giambalvo, C. Scarpello

IGC Proceedings (1997-2023)

Agronomic factors affect the productivity and efficiency of cereal-legume intercropping systems (Ofori & Stern, 1987). This research aimed to determine the effects of different plant arrangement on hay yield, nitrogen (N) content and N fixation of berseem clover-annual ryegrass mixture in a Mediterranean semi-arid environment.

Selection Of Australian Root Nodule Bacteria For Broad-Scale Inoculation Of Native Legumes, R. G. Bennett, R. J. Yates, E. L. J. Watkin, Graham W. O'Hara, M. J. Dilworth

IGC Proceedings (1997-2023)

The unique and diverse native Australian perennial legumes are under current investigation for use as pastures in Australian agriculture. Identification of root nodule bacteria (RNB) that can fix nitrogen effectively for the plant is a critical factor for the success of a legume species in agriculture (Howieson et al., 2000). Some legumes under investigation are relatively promiscuous (Lange, 1961). This trait may allow the development of a single, broad-scale inoculant that could allow inoculation of multiple species of agricultural importance, whilst more effective, specific RNB are developed in time. Aimed to identify strains that can form effective symbioses with …

Adoption Of Tropical Legume Technology Around The World: Analysis Of Success, H. M. Shelton, Steven Franzel, M. Peters

IGC Proceedings (1997-2023)

1. Examples of successful adoption of forage legumes are reported from all continents, where they delivered profitability and often provided multipurpose benefits to farmers.
2. Factors vital to successful adoption were: meeting the needs of farmers; building relevant partnerships; understanding the socio-economic context and skills of farmers; participatory involvement with rural communities; and long-term involvement of champions.
3. Organisation of seed supply, achieving scale-up and forming partnerships to implement adoption are key features.
4. Legumes remain an important but under-exploited resource for tropical farming systems. The alternative to legumes will be greater and more costly use of N-fertilisers and purchased protein concentrates.
5. The R&D …

Adoption Of Tropical Legume Technology Around The World: Analysis Of Success, H. M. Shelton, S. Franzel, M. Peters

IGC Proceedings (1997-2023)

Key points

1. Examples of successful adoption of forage legumes are reported from all continents, where they delivered profitability and often provided multipurpose benefits to farmers.

2. Factors vital to successful adoption were: meeting the needs of farmers; building relevant partnerships; understanding the socio-economic context and skills of farmers; participatory involvement with rural communities; and long-term involvement of champions.

3. Organisation of seed supply, achieving scale-up and forming partnerships to implement adoption are key features.

4. Legumes remain an important but under-exploited resource for tropical farming systems. The alternative to legumes will be greater and more costly use of N-fertilisers …

Mapping Nitrogen Fixing Shrubs In Dry Unimproved Tussock Grassland, C. C. Boswell, W. L. Lowther, P. D. Espie

IGC Proceedings (1997-2023)

Global Positioning System (GPS) was used to both map the positions of individual nitrogen-fixing shrub plants and record individual plant height and breadth dimensions, within a small catchment of dry sub-humid unimproved short tussock grassland. The distributions of different species of shrubs varied with different landscape units within the catchment. The information will provide the base data for a first approximation of the role of the shrubs in the nitrogen balance of the ecosystem, which is pivotal to the sustainability of pastoral farming in the tussock grasslands.

Importance Of Haresfoot Clover (Trifolium Arvense) As A Nitrogen Fixer In Semi-Arid Grasslands Of New Zealand, C. C. Boswell, W. L. Lowther, P. R. Espie

IGC Proceedings (1997-2023)

The aim of the study was to determine the distribution of annual haresfoot clover (Trifolium arvense) in a depleted indigenous short tussock grassland catchment in the dry subhumid MacKenzie Basin, South Island, New Zealand. Haresfoot clover was present on all landscapes, and widely distributed on lower sunny aspects, suggesting that it is an important component of the nitrogen cycle in these environments even in the absence of fertiliser application. The study was conducted during an atypically moist summer when a bloom of the annual clover occurred. Nitrogen inputs will vary with landscape and spring/summer rainfall and it is …

Estilosantes Campo Grande: An Economical And Environmental Success Forage Legume For The Tropics, Celso D. Fernandes, Bela Grof, Rosangela M. S. Resende, Jaqueline R. Verzignassi, Cesar Heraclides Behling Miranda

IGC Proceedings (1997-2023)

No abstract provided.

Understanding The Effects Of Complex Topography On Cover Crop Dynamics And Maize Production In Kentucky Agroecosystems, Samuel John Leuthold

Theses and Dissertations--Plant and Soil Sciences

In Central Kentucky, rolling hill cropland presents a number of challenges related to soil sustainability. Increased topographic complexity can lead to increased erosion, inefficient crop nutrient use and increased nutrient loss. Further, grain crop yields can be variable across both space and time in rolling hill fields and are less resilient to changes in weather conditions than flatter, more homogeneous areas. More than 30% of cropland in Kentucky has a slope greater than 3⁰, which means a large swath of the row crop production land in the state is at increased risk of contribution to soil and water resource degradation. …

Establishment And Growth Of Legumes In Acid Soils In The Falkland Islands, Sergio Radic, James H. Mcadam

IGC Proceedings (1997-2023)

No abstract provided.

Rhizobium-White Clover Symbiosis And Nitrogen Fixation Along A Soil Organic Carbon Gradient, Pieter A. Swanepoel, Philip R. Botha, Wayne F. Truter, A. Karen J. Surridge-Talbot, Alicia Van Der Merwe

IGC Proceedings (1997-2023)

Sustainable cultivated pasture production in the southern Cape region of South Africa requires management practices that will support soil quality (Swanepoel and Botha 2012). Soil organic carbon (C_org) sequestration is regarded as one of the most important ways to promote soil quality. Dairy farmers in the southern Cape attempt to increase C_org by following minimum-tillage practices. These irrigated dairy-pastures require high levels of nitrogen (N) to maintain highly productive pastures. Nitrogen fertilisers have be-come very expensive and severely strain profitability of these dairy-pastures. Forage legumes are frequently incorporated into the grass pastures to overcome economic and environmental …

Plant And Microbial Responses To Repeated Cu(Oh)2 Nanopesticide Exposures Under Different Fertilization Levels In An Agro-Ecosystem, Marie Simonin, Benjamin P. Colman, Weiyi Tang, Jonathan D. Judy, Steven M. Anderson, Christina M. Bergemann, Jennifer D. Rocca, Jason M. Unrine, Nicolas Cassar, Emily S. Bernhardt

Plant and Soil Sciences Faculty Publications

The environmental fate and potential impacts of nanopesticides on agroecosystems under realistic agricultural conditions are poorly understood. As a result, the benefits and risks of these novel formulations compared to the conventional products are currently unclear. Here, we examined the effects of repeated realistic exposures of the Cu(OH)₂ nanopesticide, Kocide 3000, on simulated agricultural pastureland in an outdoor mesocosm experiment over 1 year. The Kocide applications were performed alongside three different mineral fertilization levels (Ambient, Low, and High) to assess the environmental impacts of this nanopesticide under low-input or conventional farming scenarios. The effects of Kocide over time were …

The Soybean Rfg1 Gene Restricts Nodulation By Sinorhizobium Fredii Usda193, Yinglun Fan, Jinge Liu, Shanhua Lyu, Qi Wang, Shengming Yang, Hongyan Zhu

Plant and Soil Sciences Faculty Publications

Sinorhizobium fredii is a fast-growing rhizobial species that can establish a nitrogen-fixing symbiosis with a wide range of legume species including soybeans (Glycine max). In soybeans, this interaction shows a high level of specificity such that particular S. fredii strains nodulate only a limited set of plant genotypes. Here we report the identification of a dominant gene in soybeans that restricts nodulation with S. fredii USDA193. Genetic mapping in an F2 population revealed co-segregation of the underlying locus with the previously cloned Rfg1 gene. The Rfg1 allele encodes a member of the Toll-interleukin receptor/nucleotide-binding site/leucine-rich repeat class of …

Soil Acidity And Legume Nodulation, J G. Howieson, M. A. Ewing

Journal of the Department of Agriculture, Western Australia, Series 4

Nitrogen is a basic constituent of protien and is essential to all forms of life. Many agricultural plants are legumes - a group of plants which, in co-operation with specialised soil bacteria, fix their own nitrogen from the air. When the legume dies, the organic matter breaks down anf the nitrogen becomes available to the following crops.

Soil acidity is a major factor limitimg the successful association between legumes and their beneficial soil bacteria in Western Australia.

Bulletin No. 114 - The Movement Of Nitric Nitrogen In Soil And Its Relation To "Nitrogen Fixation", Robert Stewart, J. E. Greaves

UAES Bulletins

In the spring of 1903, we commenced at the Utah Experiment Station a series of experiments, the purpose of which was to study the development and movement of nitrates in irrigated soil. The work was so outlined that it should give some very definite results, both as to the influence of water and the plant, upon the nitric nitrogen content of the soil.