Plant Sciences Commons^™

Cycling Of N And P In Grass-Alone (Brachiaria) And Mixed Grass/Legume (Brachiaria/ Desmodium Ovalifolium) Grazed Pastures In The Atlantic Forest Region Of Brazil, R. M. Boddey, R. Tarré, R. Macedo, C. De P. Rezende, J. M. Pereira, B. J. R. Alves, S. Urquiaga

International Grassland Congress Proceedings

There are estimated to be > 80 M ha of Brachiaria pastures in the tropical regions of Brazil. When continuously grazed with only modest fertiliser inputs (and no N) these pastures can maintain reasonable cattle weight gains (> 200 kg LWG/ha per year). However, without fertiliser and when overgrazed, LWGs fall rapidly to low levels. Recent studies have shown that N and P deficiency are the most important factors limiting productivity. The objective of this study was to study fluxes of N and P in the pasture system in order to understand resilience to poor management and minimum nutrient requirements to …

Estimating Nitrogen Fixation By Pastures On A Regional Or Continental Scale, Murray Unkovich

International Grassland Congress Proceedings

With fertiliser N inputs dramatically increasing in Australia in recent years (Angus, 2001), regional and continental scale estimates of biological nitrogen fixation (BNF) are now required for assessing the risks of terrestrial and surface water eutrophication, groundwater contamination, and gaseous N emissions.

Integrating Below-Ground Ecology Into Sustainable Grassland Management, R. D. Bardgett

International Grassland Congress Proceedings

Key points

1. Grasslands produce soils that sustain an abundant and diverse soil food web, providing tremendous opportunity for below-ground interactions to influence nutrient cycling processes and plant production.

2. Fast developing areas of ecological science offer scope to harness positive outcomes of below-ground ecology for enhancing efficient cycling of nutrients in sustainable grassland systems.

The Influence Of Burning On Soil Microbial Biomass And Activity Along The Boro Route In The Okavango Delta Of Botswana, Tabo Mubyana-John, A. Banda

International Grassland Congress Proceedings

The Okavango Delta, a protected area in northeastern Botswana because of its annual flooding pattern, is the main source of water in an otherwise arid environment with a high diversity of plants and animals and forms the main tourist area in the region. However, the area is under threat from range fires. The objective of this study was to assess the influence of fire on soil microbial activity, biomass C, fungal population and diversity, and some soil properties along the Boro route of the Okavango Delta (Botswana).

Chemical Components And Effects On Soil Quality In Temperate Grazed Pasture Systems, M. H. Beare, D. Curtin, S. Thomas, P. M. Fraser, G. S. Francis

International Grassland Congress Proceedings

Key points

1. Legume/grass pastures retain feedbacks on N supply that may help to reduce losses of N to the wider environment.

2. Intensive use of N fertilisers tends to increase SOM turnover and increase losses of N to the environment.

3. Increased use of fertilisers has contributed little to soil organic matter storage in grazed pastoral systems.

Physical Constraints In Grassland Ecosystems, I. M. Young, K. Ritz, C. S. Sturrock, R. Heck

International Grassland Congress Proceedings

Key points

1. Grassland system management must account adequately for biophysical and biochemical processes.

2. Amenity turf, especially sports turf, provides an excellent case study on how biology and physics interact to impact on the functioning of a grass ecosystem.

3. Microorganisms produce hydrophobic compounds that act to decrease water ingress and alter the function of the soil-grass ecosystem.

Paraquat-Resistant Italian Ryegrass (Lolium Multiflorum) Confirmed In Louisiana, Alphonse B. Coco Iii

LSU Master's Theses

Paraquat is the only herbicide labeled for postemergence control of Italian ryegrass in sugarcane. In 2017, sugarcane farmers in Louisiana reported Italian ryegrass control failures with paraquat applications. Seeds were collected from sugarcane fields in White Castle, St. Gabriel, and Bunkie, Louisiana where control was not achieved (reduced susceptibility). Additionally, Italian ryegrass seeds were collected from a sugarcane field in Welcome, LA with a history of paraquat use and with no reported control issues (susceptible population). A dose-response study was conducted at the Louisiana State University Agricultural Center’s Sugar Research Station in February 2021 and was repeated in November 2021. …

Adoption Of Brachiaria Grasses In Mexico And Central America: A Successful Story, F. Holmann, Pedro Argel, C. E. Lascano

International Grassland Congress Proceedings

In Latin America and the Caribbean (LAC) there has been a major effort to develop new pastures technologies, to increase livestock productivity for the extensive systems prevailing in the tropical lowlands. This multi-national and inter-institutional effort was initiated through the International Network for the Evaluation of Tropical Pastures (RIEPT, by its name in Spanish), which operated from 1976 to 1996 under CIAT leadership. This network became a platform for institutions to train technicians, share forage material from existing gene banks, study the behaviour of new germplasm under different environments, and established the exchange of scientific information to extrapolate research results …

Improved Livelihoods From Grasslands; The Case Of Napier Grass In Smallholder Dairy Farms In Kenya, David Miano Mwangi, D. Romney, S. Staal, I. Baltenweck, S. Mwendia

International Grassland Congress Proceedings

In Kenya, smallholder farmers produce about 80% of the marketed milk. The farming systems vary from mixed farms with up to 10 ha of land and < 10 dairy cows (Gitau et al., 1994; Anon., 1985), to intensive smallholder dairy producers in the high human population central Kenya region with 0.9 to 2 ha of land and 3-4 dairy cows (Staal et al., 2001a). Milk production depends heavily on the cultivation of forages, with Pennisetum purpureum (Napier grass) by far the most important. An estimated 350,000 of the 600,000 smallholder farms in Kenya grow and utilize P. purpureum on their farms.

There are …

Role Of Information And Information Providers In Technology Transfer, D. Undersander

International Grassland Congress Proceedings

Technology transfer is an essential component of economic change in society. Developers of new technology often fail to realize that there is a science to technology transfer. This lack of appreciation for the skills involved in information dissemination and in activities necessary to affect a change of action in an audience often severely limits the rate and amount of technology transfer that occurs. Significant differences exist between doing a news release or writing a publication and causing audience acceptance of a new technology. The old standards of expecting adoption of a new technology simply because it “will profit farmers” or …

The Contribution Of Participatory Research: On-Farm Research, P. F. Fennessy, N. J. Daniels, S. A. Chadwick, P. A. Speck

International Grassland Congress Proceedings

Participatory research in agriculture may range from research and technology development (R&D), carried out on a research station with some involvement of farmers, through to genuine participatory research involving researchers and farmers working together. The latter involves the end-user in actually carrying out aspects of the research and/or in the development and evaluation of technology that is appropriate to commercial enterprises. Researchers often question the validity of the ‘findings of on-farm participatory research’ as they are more comfortable with the ‘controlled’ environment of the research station. However if research is to be applied appropriately on farms, it must go through …

Participatory Research For Smallholder Livestock Systems: Applying Common Sense To Complex Problems, P. M. Horne, Werner Stür

International Grassland Congress Proceedings

Key Points:

1. Participatory approaches to research (PAR) bring researchers closer to farmers, the intended users of research outputs.

2. Active, functional participation of farmers in the evaluation and development of new technologies requires researchers to make an important commitment: respecting the knowledge, skills and opinions of farmers while maintaining confidence in their own scientific knowledge.

3. Farmer experimentation is not usually suitable to provide quantitative biophysical data (this can be achieved more effectively in researcher controlled experiments), but to provide qualitative information and improve understanding. This type of information can be collected systematically to enable rigorous analysis.

4. While …

Computer-Based Forage Management Tools: Historical, Current, And Future Applications, David B. Hannaway, C. Daly, D. F. Chapman, B. B. Baker, A. S. Cooper

International Grassland Congress Proceedings

Forage management has been an important human activity since the beginning of civilization. By comparison, the personal computer has been available only in the immediate past. The software developed to deal with the complexity of climate, soil, plant, animal, and socioeconomic factors has seen huge changes in a few decades. Mainframe computers facilitated numerical calculations for exploring relationships among dozens of variables. Personal computers opened the door for more individual scientist creativity and routine communication. Web-based communication globalised the option for multidisciplinary teams to tackle problems. Forage-related computer applications abound, allowing farmers, ranchers, and others to more effectively manage the …

Soil Biology And The Emergence Of Adventive Grassland Ecosystems, T. R. Seastedt

International Grassland Congress Proceedings

The last few years have seen an explosion of information on the responses and feedbacks of soil biota to species and environmental changes. Soil biologists, plant ecologists, and biogeochemists have been searching for patterns, generality and predictability in these relationships. A few brave souls have had the courage to assemble comprehensive assessments of soil biology in our rapidly changing world. Several years ago, I reviewed Wardle’s (2002) book emphasising the links between above- and belowground components of ecosystems. That activity – as well as the present one – provided me with the opportunity to survey recent findings in soil biology. …

Paying For Our Keep: Grasslands Decision Support In More-Developed Countries, Andrew D. Moore

International Grassland Congress Proceedings

“Models in grassland science have come to stay, and so they must be made to pay for their keep. To do that, it will be necessary to improve their scientific sophistication and their management relevance...” (Seligman, 1993).

Decision support (DS) tools in grassland agriculture have also come to stay. This review will examine the ways and means by which DS tools are being made to pay for their keep, with a focus upon DS efforts from the last decade and on the lessons that arise for those who develop DS tools for grasslands. A survey of the present state of …

Decision Support For Grassland Systems In Developing Countries, P. K. Thornton

International Grassland Congress Proceedings

Key points

1. Information flows in complex systems are often themselves highly complex, and decision support approaches based on linear input-output processes may have only limited impact.

2. How decisions are made, and how they can be appropriately supported, is often incompletely understood, in part because of inadequate understanding of the objectives and attitudes of all the decision makers involved.

3. Much of the developing world faces daunting problems in the coming 30 years, and appropriate information could play a critical role in dealing with these.

4. System complexity, household variability, and institutional intricacies have to be embraced rather than …

Forage News [2022-11], Department Of Plant And Soil Sciences, University Of Kentucky

Forage News

No abstract provided.

Effects Of Intercropping On Garlic Growth In A Green Roof Setting, Kennedy Warden, Thomas Loose, Max Stone

Science University Research Symposium (SURS)

Growing crops together in the same plot, also known as intercropping, can increase soil nutrient quality and growth patterns for plants of different species. The purpose of this experiment was to determine the effect of intercropping on the growth of garlic planted on a green roof, specifically the question, “does garlic grow better in a mixed group of different species, or better in a primarily single-species group?” We divided a 2-meter plot in half, one half was devoted to garlic only while the second plot was garlic mixed with strawberries and chili peppers. We predicted that the garlic in the …

Lingnan Gardeners Newsletter (No. 64) = 彩園通訊 (第64期), Lingnan Gardeners, Centre For Cultural Research And Development, Lingnan University

Lingnan Gardeners Newsletter 嶺南彩園通訊

No abstract provided.

Near-Atomic, Non-Icosahedrally Averaged Structure Of Giant Virus Paramecium Bursaria Chlorella Virus 1, Qianqian Shao, Irina V. Agarkova, Eric A. Noel, David D. Dunigan, Yunshu Liu, Aohan Wang, Mingcheng Guo, Linlin Xie, Xinyue Zhao, Michael G. Rossmann, James L. Van Etten, Thomas Klose, Qianglin Fang

Papers in Plant Pathology

Giant viruses are a large group of viruses that infect many eukaryotes. Although components that do not obey the overall icosahedral symmetry of their capsids have been observed and found to play critical roles in the viral life cycles, identities and high-resolution structures of these components remain unknown. Here, by determining a near-atomic-resolution, five-fold averaged structure of Parameciumbursaria chlorella virus 1, we unexpectedly found the viral capsid possesses up to five major capsid protein variants and a penton protein variant. These variants create varied capsidmicroenvironments for the associations of fibers, a vesicle, and previously unresolved minor capsid proteins. Our structure …