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Citizen Scientists: Efforts By The Tri-Societies To Inject Science Into Us Policymaking, E. Bergfeld, K. Glasener

IGC Proceedings (1977-2023)

The Tri-Societies (American Society of Agronomy, Crop Science Society of America and Soil Science Society of America), the largest life science professional societies in the United States (US) dedicated to the agronomic, crop and soil sciences, encompass approximately 18,000 members globally and include approximately 14,000 certified professionals who are a direct conduit to the farming communities across the US. The Tri-Societies' US-based federal science policy programmes have been active for decades. There is a Washington, DC-based Director of Science Policy, Congressional Science Fellows (CSF) and Science Policy Interns.

Sustainability Of Permanent Grassland On A Low Moor Soil With Different N And K Nutrient Management, K. Orlovius, J. Pickert

IGC Proceedings (1977-2023)

After the reunification of Germany fertilisation with P and K was strongly reduced in the eastern states of Germany due to the poor financial situation of the farms. Particularly on sites with a low nutrient delivery capacity, such a nutrient management strategy implies the risk of decreasing soil fertility. On a low moor soil with permanent grassland a 4 - year trial with different N and K fertilisation was set up to study the development of dry matter production and K concentrations in the grass.

A Protein Kinase Coordinates Cycles Of Autophagy And Glutaminolysis In Invasive Hyphae Of The Fungus Magnaporthe Oryzae Within Rice Cells, Gang Li, Ziwen Gong, Nawaraj Dulal, Margarita Marroquin-Guzman, Raquel O. Rocha, Michael Richter, Richard A. Wilson

Department of Plant Pathology: Faculty Publications

The blast fungus Magnaporthe oryzae produces invasive hyphae in living rice cells during early infection, separated from the host cytoplasm by plantderived interfacial membranes. However, the mechanisms underpinning this intracellular biotrophic growth phase are poorly understood. Here, we show that the M. oryzae serine/threonine protein kinase Rim15 promotes biotrophic growth by coordinating cycles of autophagy and glutaminolysis in invasive hyphae. Alongside inducing autophagy, Rim15 phosphorylates NADdependent glutamate dehydrogenase, resulting in increased levels of α- ketoglutarate that reactivate target-of-rapamycin (TOR) kinase signaling, which inhibits autophagy. Deleting RIM15 attenuates invasive hyphal growth and triggers plant immunity; exogenous addition of α-ketoglutarate prevents these …

A Protein Kinase Coordinates Cycles Of Autophagy And Glutaminolysis In Invasive Hyphae Of The Fungus Magnaporthe Oryzae Within Rice Cells, Gang Li, Ziwen Gong, Nawaraj Dulal, Margarita Marroquin-Guzman, Raquel O. Rocha, Michael Richter, Richard Wilson

Department of Plant Pathology: Faculty Publications

The blast fungus Magnaporthe oryzae produces invasive hyphae in living rice cells during early infection, separated from the host cytoplasm by plantderived interfacial membranes. However, the mechanisms underpinning this intracellular biotrophic growth phase are poorly understood. Here, we show that the M. oryzae serine/threonine protein kinase Rim15 promotes biotrophic growth by coordinating cycles of autophagy and glutaminolysis in invasive hyphae. Alongside inducing autophagy, Rim15 phosphorylates NADdependent glutamate dehydrogenase, resulting in increased levels of α- ketoglutarate that reactivate target-of-rapamycin (TOR) kinase signaling, which inhibits autophagy. Deleting RIM15 attenuates invasive hyphal growth and triggers plant immunity; exogenous addition of α-ketoglutarate prevents these …

A Protein Kinase Coordinates Cycles Of Autophagy And Glutaminolysis In Invasive Hyphae Of The Fungus Magnaporthe Oryzae Within Rice Cells, Gang Li, Ziwen Gong, Nawaraj Dulal, Margarita Marroquin-Guzman, Raquel O. Rocha, Michael Richter, Richard Wilson

Department of Plant Pathology: Faculty Publications

The blast fungus Magnaporthe oryzae produces invasive hyphae in living rice cells during early infection, separated from the host cytoplasm by plantderived interfacial membranes. However, the mechanisms underpinning this intracellular biotrophic growth phase are poorly understood. Here, we show that the M. oryzae serine/threonine protein kinase Rim15 promotes biotrophic growth by coordinating cycles of autophagy and glutaminolysis in invasive hyphae. Alongside inducing autophagy, Rim15 phosphorylates NADdependent glutamate dehydrogenase, resulting in increased levels of α- ketoglutarate that reactivate target-of-rapamycin (TOR) kinase signaling, which inhibits autophagy. Deleting RIM15 attenuates invasive hyphal growth and triggers plant immunity; exogenous addition of α-ketoglutarate prevents these …

Molecular Identification Of Oomycete Species Associated With Woody Plants In Louisiana And Survey Of Oomycete Species Associated With Live Oak Trees Planted On The Louisiana State University Campus, Hamilton Crockett

LSU Master's Theses

Three Oomycetes genera, Phytophthora, Phytopythium and Pythium, contain many important plant pathogens. Historically, Phytophthora infestans, responsible for the great Irish potato famine, and Phytophthora ramorum, causal agent of sudden oak death disease, are the two better-known high impact pathogens. The LSU AgCenter Plant Diagnostic Center (PDC) has been isolating putative Phytophthora and related species from combined root and soil samples collected from various woody ornamentals and trees for over a decade. In August of 2016, Louisiana received torrential rains, which resulted in historic flooding in several southern parishes. During subsequent years, the PDC staff isolated a …

Arkansas Corn And Grain Sorghum Research Studies 2022, Victor Ford, Jason Kelley, Nathan Mckinney Ii

Arkansas Agricultural Experiment Station Research Series

The 2022 edition of the Arkansas Corn and Grain Sorghum Research Studies Series includes research results on topics pertaining to corn and grain sorghum production, including weed, disease, and insect management; economics; sustainability; irrigation; post-harvest drying; soil fertility; mycotoxins; cover crop management; and research verification program results. Our objective is to capture and broadly distribute the results of research projects funded by the Arkansas Corn and Grain Sorghum Board. The intended audience includes producers and their advisors, current investigators, and future researchers. The Series serves as a citable archive of research results.

Reports in this publication are 2–3 year summaries. …

Maintaining Grassland Plant Diversity While Controlling Woody Plant Encroachment, James Stubbendieck, Kay L. Kottas, S. J. Tunnell, S. J. Palazzolo

IGC Proceedings (1977-2023)

The tallgrass prairie region of the United States is a fragmented grassland ecosystem. Much of the 1 to 2% of the remaining prairie is being degraded by invading woody plants, which frequently results in a shift from grassland to woodland. Smooth sumac (Rhus glabra L.), a shrub native to the region, can rapidly increase in density and become dominant in the plant community. Prescribed fire alone is not a constraint to this resprouting species (Stubbendieck et al., 2003). Herbicides are useful tools for managing woody plants in grasslands, but the negative response of desirable plants to herbicides is …

Do Species And Functional Diversity Indices Reflect Changes In Grazing Regimes And Climatic Conditions In Northeastern Spain?, F. De Bello, J. Leps, M. T. Sebastià

IGC Proceedings (1977-2023)

Understanding the mechanisms that maintain biodiversity in various ecosystems enables the development of management practices that prevent degradation (Canals & Sebastia, 2000). Each diversity index reflects some compositional properties and could be influenced differently by stress and disturbance factors (Magurran, 2004). In this study, we aim to reveal 1) which management practices and environmental factors affect biodiversity in rangelands of northeastern Spain and 2) the relationship between species diversity and functional diversity (SD and FD).

Impact Of Grazing Regimes On Mean Sward Height: Implications For The Management Of Bird Habitats In Agricultural Landscapes, M. Tichit, D. Durant, E. Kernéïs

IGC Proceedings (1977-2023)

Grazing in wet grasslands is a key process to manage foraging and nesting habitats for waders. Grazing has positive and negative effects related to the importance of sward conditions for these species and to nest-trampling by cattle. For settlement and nesting, lapwings need a short sward ( ≤ 10cm; see Durant et al., this congress). However, when lapwings settle in early spring, grasslands seldom are grazed yet, due to low soil carrying capacity. We studied the effect of autumn and winter grazing regimes on sward structure in early spring, and the effect of grazing regime in early spring on …

Soil Carbon Sequestration Under Three Years Of No-Till Forage Cropping Systems, D. H. Min, J. D. Deyoung, Richard Leep

IGC Proceedings (1977-2023)

The effects of reduced tillage on soil organic carbon (SOC) are generally well established (Chan et al., 2002; Cabardella & Elliott, 1992). The effects of different crops are also somewhat understood (Drinkwater et al., 1998). However, many of these studies are done in the laboratory to study the effects of crop residues on SOC. Many forage-based systems have very little crop residue returned to the field. What residue does return is often in the form of manure or compost, which is usually broken down much more rapidly than most crop residues. The objective of this study is to …

Number And Viability Of Seeds Recovered From Faeces Of Ruminant Animals, Alaba O. Jolaosho, Olufemi S. Onifade, O. M. Arigbede, Jimoh A. Olanite, T. O. Akinola

IGC Proceedings (1977-2023)

Ruminants play a significant role in the dissemination of plant seeds as a result of ingested seeds during grazing on pasture escaping digestion that are voided with the faeces and returned to the seed bank (Russi et al., 1992).

Population Changes Of Invasive Annuals In California Annual And Perennial Grasslands, Richard King

IGC Proceedings (1977-2023)

Some non-native annual forbs and grasses can be invasive in California's annual grassland region. Taeniatherum caput-medusae (L.) Nevski and Centaurea solstitialis L. can spread quickly, become nearly monospecific stands, and reduce carrying capacity for livestock and wildlife. Centaurea also can be toxic to horses. Lathyrus hirsutus L. is less invasive, but the seed is toxic to various livestock. Since 1991, the author has raised beef cattle on 16 ha of predominantly annual grassland where these 3 species occur, and a family member has raised cattle on approximately 40 ha of adjacent property. Surface soils in this hilly land are …

The Effect Of Sheep Grazing At Two Stocking Rates On The Seedling Recruitment Of Grassland Forbs, Johannes Isselstein, Markus Kowarschik, S. Bonn, M. Hofmann

IGC Proceedings (1977-2023)

Limitations for seedling recruitment are major constraints to maintain and enhance plant species diversity in productive grasslands (Bakker & Berendse 1999). Grass sward condition plus species-specific requirements for germination and survival determine the recruitment success. Therefore, a field experiment investigated the establishment of oversown seeds from wildflower forbs in relation to grass sward management.

A Basis For Designing Policies To Optimize Soil Carbon Sequestration In Southeastern Us Grasslands, Joel R. Brown, D. L. Faulkner

IGC Proceedings (1977-2023)

Increasing the amount of carbon (C) stored in terrestrial ecosystems is an important part of most national greenhouse gas (GHG) management strategies. Among the policy and program options available to achieve increased C sequestration, improved management of grasslands offers an attractive option to both reduce atmospheric concentrations of C and enhance environmental co-benefits (soil quality, water quality, food and fibre production, and wildlife habitat). In the United States, incentives for applying improved land management practices come primarily via federal government conservation programs administered by the United States Department of Agriculture (USDA). While private sector markets offer opportunities to increase the …

The Nature Of Sequestered Carbon In Different Irish Mineral Soils, C. M. Byrne, D. Fay, J. A. Ferreira, M. H. B. Hayes

IGC Proceedings (1977-2023)

Humic substances (HS) provide the major sinks for carbon (C) in soils. Although HS have a degree of resistance to microbial degradation, they are degraded in time. Humin, the HS component in association with the soil mineral colloids, has greatest resistance to degradation. To understand the extent to which soil can be a sink for C it is important to know the soil mineralogy, and to be aware of aspects of the structures of the humic components. Enhanced biological oxidation occurs in soils in long term cultivation. Its effects can be observed by comparing the amounts and compositions of the …

The Effect Of Dairy Cow Genotype On Modelled Greenhouse Gas Emissions Derived From Pasture Based Milk Production Systems, Dan K. Lovett, L. Shalloo, P. Dillon, Frank O'Mara

IGC Proceedings (1977-2023)

A three-year systems comparison study was undertaken to see if progressively increasing the genetic potential for milk production of the dairy cow is desirable within pastoral based systems of spring milk production (Kennedy et al., 2002). The production data was inputted into the Moorepark Dairy System Model (MDSM) (Shalloo et al., 2004) to describe the economic, biological and production efficiency of each system. Output was then used to model whole farm greenhouse gas (GHG) emissions (Lovett et al., in press) from the nine systems studied (three concentrate levels by three genotype levels). Only the genotype effects are …

Methane Of Animal Origin In Cattle Fed High Or Low Tannin Sorghum Silage, T. T. Berchielli, S. G. Oliveira, M. P. Pedreira, O. Primavesi, M. A. Lima, R. Frighetto

IGC Proceedings (1977-2023)

The harmful or beneficial effects associated with the presence of tannin in plants depends on its concentration and form. One of these beneficial effects is the reduction of the production of methane in the rumen (Woodward et al., 2001). This study financed by FAPESP aimed to evaluat the effect of diets containing low or high tannin sorghum silage supplements on dry matter intake (DMI) and methane production in cattle.

Field Measurements Of Ruminal Methane Of Cattle Grazing Tropical Grasses, M. P. Pedreira, O. Primavesi, M. A. Lima, R. Frighetto, T. T. Berchielli

IGC Proceedings (1977-2023)

Ruminal methane production represents energy losses from ingested feed that should be utilised to maintain body weight or to generate products. Quantitatively, daily methane production varies according to amount and quality of ingested dry matter (DM), as well as physiological status of the animal.

Hedgerow Systems And Livestock In Philippine Grasslands: Ghg Emissions, D. B. Magcale-Macandog, E. Abucay, R. G. Visco, R. N. Miole, E. L. Abas, G. M. Comajig, A. D. Calub

IGC Proceedings (1977-2023)

Hedgerow systems are widely adopted in the smallholder farms in the sloping grassland areas of Claveria, Mindanao, Philippines. The system is effective in addressing soil erosion problems and in conserving the topsoil. Gmelina arborea and Eucalyptus deglupta are two fast-growing timber species that are planted in hedgerow systems while maize is planted in the alley areas in between the hedgerows. Livestock holdings are widespread in Claveria, with 74% of the households having livestock. Cattle and carabao are the most common livestock in smallholder farms providing draught power for land preparation and transportation. In hedgerow systems, fodder tree leaves and crop …

The Effect Of Soil Type And Climate On Modelled Greenhouse Gas Emissions Derived From Pasture Based Milk Production Systems, Dan K. Lovett, L. Shalloo, P. Dillon, Frank O'Mara

IGC Proceedings (1977-2023)

The ability of spring calving dairy farmers to exploit herbage production can be limited by soil type and climatic conditions. Previous work, using the Moorepark Dairy System Model (MDSM) (Shalloo et al., 2004) demonstrated differences in terms of biological and production efficiency for two contrasting sites. This study models whole farm greenhouse gas (GHG) emissions (Lovett et al., in press) from two dairy systems, the Moorepark Standard System (MSS, Co. Cork) and the Kilmaley Standard System (KSS,Co. Clare), classified as lower and high rainfall (1025 and 1614 mm yr) and free draining versus poor draining respectively.

Quantification Of Co2 Exchange In Grassland Ecosystems Of The World Using Tower Measurements, Modeling And Remote Sensing, Tagir Gilmanov, M. W. Demment, B. K. Wylie, K. Akshalov, D. D. Baldocchi, L. Belelli, J. A. Bradford, G. G. Burba, R. L. Coulter, W. A. Dugas, W. E. Emmerich, L. B. Flanagan, A. B. Frank, J. Fuher, M. R. Haferkamp, M. B. Jones, D. A. Johnson, T. Laurila, A. Lohila, T. P. Meyers, P. C. Mielnick, J. A. Morgan, M. Nasyrov, C. E. Owensby, M. S. Pekour, K. Pilegaard, A. Raschi, N. Z. Saliendra, M. J. Sanz, P. L. Sims, R. H. Skinner, J. F. Sousanna, A. E. Suyker, L. L. Tieszen, Z. Tuba, R. Valentini, S. B. Verma, E. A. Laca

IGC Proceedings (1977-2023)

Grasslands cover significant areas in nontropical regions, perform essential biogeochemical functions and represent important natural and agricultural resource. Nevertheless, in contrast to forests and agroecosystems, no flux measurement-based global summary of their CO₂ exchange, sequestration potential, and role in mitigation of the greenhouse effect were available.

The Influence Of Local Immigration And Extinction Of Species On Spatial Heterogeneity Of Vegetation In Semi-Natural Grasslands In Japan, Taisuke Yasuda, Masae Shiyomi, T. Egawa, K. Sei, R. Ishikawa, S. Takahashi

IGC Proceedings (1977-2023)

Spatiotemporal variation in the local immigration and extinction of species in a community may form and change the spatial heterogeneity (SH) of vegetation but few studies have evaluated the influences of these processes on SH. SH often occurs in grassland grazed by cattle and sheep. Understanding the formation and dynamics of SH is important because SH profoundly affects local and regional ecological processes. We propose a new way to quantify the effect of the local immigration and extinction of species on SH, and try to clarify the influence of the processes on SH

Cattle Slurry Amended With Nitrification Inhibitors: Effects On Nitrous Oxide, Dinitrogen And Methane Emissions, J. P. Carneiro, L. Cardenas, D. Hatch, H. Trindade, J. Hawkins, David Scholefield, D. Chadwick

IGC Proceedings (1977-2023)

In recent decades, a very intensive dairy farming system has been developed in northern Portugal. Considering the appreciable amounts of slurry generated and the small farm areas for spreading, this activity involves large annual inputs of N with the risk of undesirable consequences for the environment. Emission of greenhouse gases from agricultural sources, such as N₂O (originating from nitrification and denitrification) and CH₄, therefore need to be reduced. The aim of this laboratory experiment was to evaluate the effectiveness of two nitrification inhibitors (dicyandiamide (DCD) and 3,4-dimethylpyrazole phosphate (DMPP)) in reducing nitrification and subsequent denitrification after …

Methane Production By Cattle Grazed At Two Stocking Rates On A Semi-Natural Grassland, Cesar S. Pinares-Patiño, Y. Rochette, M. Fabre, J.-P. Jouany, C. Martin

IGC Proceedings (1977-2023)

Global warming induced by the human-enhanced concentrations of greenhouse gases (GHG) in the atmosphere is a major environmental concern of our day. Enteric methane (CH₄) is the most important GHG associated with grazing livestock. The emissions of methane may be influenced by environmental conditions and grazing management. Stocking rate (SR), the number of animals per unit of land area, remains the simplest management tool in pastoral farming. However, little is known about the influence of SR on CH₄ emission. The objective of this study was to compare the CH₄ emissions from cattle managed under low and …

Carbon Accumulation Under Brachiaria Pastures In The Brazilian Cerrado In Relation To Their Productivity, R. M. Boddey, S. P. Braz, R. S. M. Dos Santos, B. J. R. Alves, S. Urquiaga

IGC Proceedings (1977-2023)

Vast areas of land within Brazil has been converted from either the native vegetation of the Amazon and Atlantic forests or the native vegetation (NV) of the central savanna region (the Cerrado) to Brachiaria spp pastures. Productive pastures (PPs) in these regions eventually accumulate soil carbon (C) in excess of levels under native vegetation. However the effect of pasture degradation on soil C stocks has not been reported. We compared soil C stocks under both NV and Brachiaria pastures varying in productivity according to the indicators of Oliveira et al. (2004) over 5 sites in the Cerrado region.

Comparison Of Methodological Tools In Tropical Soil Carbon Sequestration Field Research, Bram Van Putten, M. C. Amézquita

IGC Proceedings (1977-2023)

Models play a crucial role in studying complex systems like soil Carbon sequestration processes (Hanson et al., 2001). A Carbon sequestration research project is currently under way in pasture and silvopastoral systems of four Tropical American ecosystems. A main research question is the identification of Land Management Systems (LMS) that exhibit optimal soil Carbon sequestration capacity (identification question). Another main issue is the extrapolation of data in space and time (extrapolation question).

Effects Of Tropical Legumes With Contrasting Tannin Contents And Mixtures Of Them On In Vitro Ruminal Fermentation And Methanogenesis, H. D. Hess, F. L. Valencia, P. Avila, C. E. Lascano, Michael Kreuzer

IGC Proceedings (1977-2023)

Previous in vitro experiments have showed that the supplementation of a low-quality grass diet with Arachis pintoi or Cratylia argentea (legumes low in tannins) enhanced ruminal fermentation and methane release, whereas the supplementation with Calliandra calothyrsus (rich in tannins) decreased methane release and suppressed organic matter (OM) degradation and N turnover (Hess et al., 2003). It was hypothesised that a mixture of tanniniferous legumes with legumes free of or low in tannins would result in a methane-suppressing effect but without impairing ruminal nutrient degradation.

A Simulation Study Of Nitrous Oxide Emissions From A Fertilised, Grazed Grassland Site In Ireland, Michael J. Hawkins, J. Connolly, B. Hyde, M. Ryan, R. P. O. Schulte

IGC Proceedings (1977-2023)

Nitrous oxide (N₂O) emissions from grazed grassland are understood to be strongly influenced by the availability of a mineral N source, soil temperature and soil water content (Skiba & Smith, 2000). We derive an empirical model of emissions based on these factors and use it to simulate daily emissions from a fertilised, grazed grassland site in Wexford, Ireland, under different application schedules and climatic conditions for the period 1994 to 2001, inclusive (Table 1).

Cattle Overwintering Areas In Middle-European Conditions - Important “Point” Sources Of Nitrous Oxide Emissions, M. Šimek, J. Hynšt, P. Brůček, J. Čuhel, D. Elhottová, H. Šantrůčková, V. Kamír

IGC Proceedings (1977-2023)

Nitrous oxide (N₂O) emissions in grazed grasslands are strongly influenced by animal excreta (Fowler et al., 1997). In addition, soil compaction caused by animal traffic significantly influences soil physical conditions and thus directly or indirectly impacts on the microbial processes producing N₂O. In the Czech Republic pastures are mostly located in hilly and mountain areas. During the growing season, cattle are typically grazing, while during the winter the animals are concentrated near the animal house on a relatively small plot called an "overwintering area". The objective of this study was to estimate the fluxes of …