Agricultural Science Commons^™

Front Matter [23rd International Grassland Congress Proceedings], National Organizing Committee, International Grassland Congress

IGC Proceedings (1977-2023)

No abstract provided.

School Gardens: Cultivating A Child’S Nutritional Habits, Environmental Knowledge, And Sustainability Practices, Jeffrey Meltzer

Honors Theses

School gardens have existed since the late nineteenth century and today are becoming increasingly popular in many parts of the world, including where I studied in Maine and Australia (AUS). Multiple organizations support school gardens in Maine, including the Maine School Garden Network, which has over 125 registered school gardens. In AUS, the Stephanie Alexander Kitchen Garden Foundation primarily supports the school garden movement and has over 800 registered school gardens. While many researchers have studied school gardens, few have compared two countries, focused on environmental sustainability, or investigated Maine in particular. This thesis combines information from literature reviews, and …

Target-Directed Biosynthetic Evolution: Redirecting Plant Evolution To Genomically Optimize A Plant’S Pharmacological Profile, Dustin Paul Brown

Theses and Dissertations--Neuroscience

The dissertation describes a novel method for plant drug discovery based on mutation and selection of plant cells. Despite the industry focus on chemical synthesis, plants remain a source of potent and complex bioactive metabolites. Many of these have evolved as defensive compounds targeted on key proteins in the CNS of herbivorous insects, for example the insect dopamine transporter (DAT). Because of homology with the human DAT protein some of these metabolites have high abuse potential, but others may be valuable in treating drug dependence. This dissertation redirects the evolution of a native Lobelia species toward metabolites with greater activity …

The Effect Of Turning Frequency On In-Vessel Compost Processing And Quality, Paige E. Boyle, Mary C. Savin, Lisa S. Wood

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Composting can contribute to the zero waste initiative on the University of Arkansas (UA) campus. In-vessel systems like Earth Tubs™ are purported to provide better control of temperature and moisture during the composting process. Turning materials helps facilitate microbial activity and thermophilic composting. The goal of this research was to determine if turning frequency affects processing or final quality of compost made with pre- and post-consumer food waste feedstock and a wood chip bulking agent. Turning frequencies (treatment) of 3 days/week and 7 days/ week were evaluated simultaneously throughout three sequential runs. Temperature, pH, electrical conductivity (EC), and moisture content …

Fall Seed Guide 2015, Teshome Regassa, P. Stephen Baenziger, Stephen N. Wegulo, Greg Kruger, Dipak K. Santra

Department of Agronomy and Horticulture: Faculty Publications

Crops included in this guide are winter wheat, winter barley, and triticale. You may receive this guide in the mail or through the University of Nebraska Extension network. The data and other information this guide is can be found at our web site: http://cropwatch.unl.edu/varietytest/ and http://www.unl.edu/ncia. Additional information is available at the wheat variety virtual tour web site http://cropwatch.unl.edu/wheat/virtual or the winter wheat variety selection tool page http:// citnews.unl.edu/winter_wheat_tool/index.shtml. The last season was hard on Nebraska winter wheat. Emergence was poor in the west due to dry conditions. On the other hand, some plots in the east had to be …

Model And Sensor-Based Recommendation Approaches For In-Season Nitrogen Management In Corn, L. J. Thompson, R. B. Ferguson, N. Kitchen, D. W. Frazen, M. Mamo, H. Yang, J. S. Schepers

Department of Agronomy and Horticulture: Faculty Publications

Nitrogen management for corn (Zea mays L.) may be improved by applying a portion of N in-season. This investigation was conducted to evaluate crop modeling (Maize-N) and active crop canopy sensing approaches for recommending in-season N fertilizer rates. These approaches were evaluated during 2012–2013 on 11 field sites, in Missouri, Nebraska, and North Dakota. Nitrogen management also included a no-N treatment (check) and a non-limiting N reference (all at planting). Nitrogen management treatments were assessed for two hybrids and at low and high seeding rates, arranged in a randomized complete block design. In 9 of 11 site-years, the sensor-based …

Front Matter [Preface And List Of Contributors], National Organizing Committee, International Grassland Congress

IGC Proceedings (1977-2023)

No abstract provided.

Promising Forage Options To Enhance Livestock Production In Mediterranean Climate Agricultural Systems, Serkan Ates, Hayley C. Norman, Hichem Ben Salem, Bradley Nutt, Harun Cicek

IGC Proceedings (1977-2023)

The increasing demand for food, fibre and animal products inevitably requires intensifying agricultural production worldwide. This can present a number of environmental and farming systems challenges in Mediterranean climate areas of the world. Developments of novel strategies, employing ecologically sound intensification practices, are crucial to enhance production in the Mediterranean agropastoral production systems. In this paper, we have discussed forage based systems that improve productivity, profitability, environmental quality and resilience of the farming systems. Key opportunities include better use and integration of diverse genetic resources, new agronomic techniques and the utilization of perennial forage plants that are adapted to land …

New Methodologies For Grasslands Monitoring, Katarzyna Dabrowska-Zielinska, Piotr Goliński, Marit Jorgensen, Jørgen Mølmann, Gregory Taff, Monika Tomaszewska, Barbara Golińska, Maria Budzynska, Martyna Gatkowska

IGC Proceedings (1977-2023)

Monitoring grassland areas to assess changes in their condition over time has been the subject of a lot of research at different scales. Initially the techniques focused on field-based measurements, and modelling. However, several obtained data were site specific. Based on the increase in availability of remote sensing data and products, there is an expectation that remote sensing can provide rapid and definite answers to the challenges of detecting and monitoring grassland conditions and associated changes in productivity. At the time of European Copernicus Programme, the new possibilities of satellite data from the group of Sentinel satellites give the new …

Grazing Management Options For Maintaining Optimum Pasture Composition And Utilization, Glen E. Aiken

IGC Proceedings (1977-2023)

Global demand for meat and dairy products will continue to increase over the 21st century, however, the global forage-based livestock industry will be challenged in meeting production goals with minimal impact of the environment. Sustainable production of grazing livestock will depend on the use of carefully planned grazing management strategies. Development of a grazing management plan involves making two decisions: determining the livestock density at which pastures are stocked and settling on the method used to graze the pastures. Stocking rate indirectly affects output per animal and per hectare through its direct effect on forage mass and pasture composition. A …

Enhancing Grassland Productivity Through Disease Management Of Grass And Forage Species, Tingyu Duan, Chunjie Li, Yanzhong Li, Binhua Yu, Zhibiao Nan

IGC Proceedings (1977-2023)

The total area of grassland in China is about 400 million hectares, accounting for 41.7% of the country’s land area, which plays important role in ecological construction and food security assurance of the national. However, diseases of grass and forage limited the development of the pastoral agriculture. There are more than1500 new diseases were reported in the past 16 years with more and more new diseases were discovered. The damage to grassland is becoming more severe with the known diseases prevalent areas expanding.

Management Of Pasture Soils: Biochar Stability, Carbon Storage Potential And Its Effect On Production And Quality, Bhupinder Pal Singh, Yunying Fang, Mark Boersma, Damian Collins, Lukas Van Zwieten, Lynne M. Macdonald

IGC Proceedings (1977-2023)

The use of biochar has been proposed as a stable carbon (C) amendment with long-term carbon (C) storage potential in agricultural soils while improving primary productivity. However, this concept has not been widely tested in contrasting soils under temperate pasture systems. To address this knowledge gap, a ¹³C-labelled biochar, produced from Eucalyptus saligna biomass by slow pyrolysis (450° C; d¹³C -36.7‰) was surface (0"10 cm) applied in C₃ dominated, annual temperate pasture systems across Arenosol, Cambisol and Ferralsol. The results show that only 2% of the applied biochar-C was mineralised in a relatively clay- and C-poor …

Grassland Renovation And Consequences For Nutrient Management, Johannes Isselstein, Manfred Kayser

IGC Proceedings (1977-2023)

Sward degradation is a serious threat to the functioning of grassland and the provision of ecosystem services. Renovation measures are frequently applied in order to restore degraded swards. However, the success is highly variable and substantial tradeoffs are often found following renovation such as among agronomic and environmental services. Starting from a general classification of renovation measures the paper investigates the processes induced by renovation that lead to a change of the vegetation and that affect carbon and nitrogen fluxes. These processes are strongly interrelated and dependent on site, climate and management condition as well as on the time scale. …

Arkansas Cotton Variety Test 2014, Fred Bourland, A. Beach, C. Kennedy, L. Martin, A. Rouse, B. Robertson

Arkansas Agricultural Experiment Station Research Series

The primary goal of the Arkansas Cotton Variety Test is to provide unbiased data regarding the agronomic performance of cotton varieties and advanced breeding lines in the major cotton-growing areas of Arkansas. This information helps seed companies establish marketing strategies and assists producers in choosing varieties to plant.

Potential For Crop Production Increase In Argentina Through Closure Of Existing Yield Gaps, Fernando Aramburu Merlos, Juan Pablo Monzon, Jorge L. Mercau, Miguel Taboada, Fernando H. Andrade, Antonio J. Hall, Esteban Jobbagy, Kenneth Cassman, Patricio Grassini

Department of Agronomy and Horticulture: Faculty Publications

Favorable climate and soils for rainfed crop production, together with a relatively low population density,results in 70–90% of Argentina grain production being exported. No assessment to date has tried to estimate the potential for extra grain production for soybean, wheat and maize, which account for 78%of total harvested area, by yield gap closure on existing cropland area and its impact at a global scale.The objectives of this paper are (i) to estimate how much additional grain could be produced without expanding crop area by closing yield gaps in Argentina, (ii) to investigate how this production and yield gaps varies across …

Plants Coping Abiotic And Biotic Stresses: A Tale Of Diligent Management, Hatem Rouached, Sikander Pal, Shimon Rachmilevitch, Marc Libault, Lam-Son Phan Tran

Department of Agronomy and Horticulture: Faculty Publications

Plants unlike other living forms are sessile thereby facing severe biotic and abiotic stresses. Plants have evolved different efficient defence responses which thrive upon a number of intrinsic factors, such as genotypic and phenotypic constitutions and developmental circumstances, and extrinsic factors like severity and duration of the stresses. Stress management uses molecular and biochemical level controls, the competence, and speed, at which a stress signal is perceived and transmitted to generate stress signal molecules and activate stress-protective mechanisms. A well-concerted action of the plants’ competence at morphological, physiological, biochemical, and molecular strata regulates numerous adaptive responses to biotic and abiotic …

Calibration And Validation Of The Hybrid-Maize Crop Model For Regional Analysis And Application Over The U.S. Corn Belt, Xing Liu, Jeff Andresen, Haishun Yang, Dev Niyogi

Department of Agronomy and Horticulture: Faculty Publications

Detailed parameter sensitivity, model validation, and regional calibration of the Hybrid-Maize crop model were undertaken for the purpose of regional agroclimatic assessments. The model was run at both field scale and county scale. The county-scale study was based on 30-yr daily weather data and corn yield data from the National Agricultural Statistics Service survey for 24 locations across the Corn Belt of the United States. The field-scale study was based on AmeriFlux sites at Bondville, Illinois, andMead, Nebraska. By using the one-at-a-time and interaction-explicit factorial design approaches for sensitivity analysis, the study found that the five most sensitive parameters of …

Grassland Resources And Protections In The Yellow River Source Zone On The Qinghai-Tibet Plateau, Xilai Li, Gary J. Brierley, Youming Qiao, George L. W. Perry, Jay King Gao

IGC Proceedings (1977-2023)

This paper summarises resources and protections of the Yellow River Source Zone on the Qinghai-Tibet Plateau. A concerted effort has been made to address concerns for overgrazing on the alpine steppe and alpine meadow landscapes in the source zone of the Yellow River. An assessment of the impacts of overgrazing includes consideration of the role of small mammals (on the one hand they are considered as a critical ecosystem engineer, on the other they are perceived as a major threatening pest). Analyzed in this paper are management options in the restoration of degraded grasslands.

Importance Of Livestock Production From Grasslands For National And Local Food And Nutritional Security In Developing Countries, Iain A. Wright

IGC Proceedings (1977-2023)

Grazing lands cover more than a quarter of the world’s land surface, often on land that is unsuitable for other forms of use. Despite the perception that productivity is inherently low, the contribution of grasslands in food security in developing countries is significant. However the challenges of spatial and temporal variability of primary productivity need to be managed and mobility of livestock is key to this. Appropriate land management and governance arrangements are essential for facilitating this mobility and for creating the circumstances in which technical options for reducing variability and risk in livestock keeping can be deployed and to …

Selection And Basis For 2,4-D (2,4-Dicholorphenoxyacetic Acid) Tolerance In Red Clover (Trifolium Pratense), Tara L. B. Lewis

Theses and Dissertations--Plant and Soil Sciences

A red clover (Trifolium pratense) population (UK), from a cross between the cultivar Kenland and a 2,4-D tolerant population (Florida), was recurrently selected for 2,4-D tolerance with evaluations after the 6^th, 7^th, and 8^th selection cycles. All UK populations were more 2,4-D tolerant than Kenland. The 2,4-D tolerance following the 6^th selection cycle was similar to the Florida population and tolerance was increased following 7 and 8 cycles of selection by removing plants showing 2,4-D injury and doubling the rate of 2,4-D used for selection.

Yield and forage quality were evaluated in …

Nutrient Availability And Dynamics Of Compost Bedded Pack Dairy Barn Waste, Leslie Hammond

Theses and Dissertations--Plant and Soil Sciences

Increased adoption of compost bedded pack dairy barns (CBP), a relatively new housing and manure handling strategy, warrants study to facilitate proper use of CBP waste as a soil amendment. This study: 1) characterized in situ nutrient content and availability of CBP waste in terms of nitrogen (N) and phosphorus (P); 2) examined the decomposition of surface-applied CBP waste compared to an alternative processed solid waste amendment; 3) examined nutrient dynamics of incorporated CBP waste in high and low soil test phosphorus (STP) environments. Quick anaerobic mineralization assays revealed that bed management affects nutrient content and availability of CBP waste. …

Production, Persistence And Diversity Of Species In Temperate Grasslands, Meredith L. Mitchell, Brendan P. Christy

IGC Proceedings (1977-2023)

Temperate grassland areas are considered to be semi-arid, with rainfall typically between 250 and 500 mm, much of it occurring in the late spring and early summer. Grazing plays an important role in all these grasslands with impacts on diversity and persistence. Against this assumption that seasonal productivity would be more uniform within a pasture that was diverse, the research suggested that species rich pastures were less stable, because this species richness was composed of non-perennial, volunteer and weed species. This paper explores the concept that systems diversity of temperate grassland does not always equate to production. In these systems …

Using Various Lactic Acid Bacteria Strains During Forage Conservation Towards Fermentation, Storage, Nutritive Value And Safety Improvement, Jonas Jatkauskas, Vilma Vrotniakiene

IGC Proceedings (1977-2023)

Many research efforts have been devoted to find ways how to produce silages with maximum nutritive value, good fermentation and low mould and yeast counts. While there are different objectives in using silage additives, the main objectives are to improve fermentation and reduce dry matter loss, and to prevent secondary fermentation at feed out time. This paper presents our most significant and recent investigations on forage inoculation before ensiling that have a potential for beneficial application on grassland and ruminant nutrition.

Traditional Livestock Production And Growth Opportunities In India, S. M. Deb

IGC Proceedings (1977-2023)

Livestock and animal health development projects need to be based on an understanding of livestock production systems because different systems need different approaches particularly in view of degradation of environment combined with population pressure. In India, the livestock production system is primarily traditional, consisting of mixed-farming and pastoral systems, therefore, development of marginal and smallholder mixed farms must aim at intensification of the total production system. Resource-poor farming systems may aim at the improved management of the various livestock species in backyards. Pastoral systems must focus on effective management of grazing pressure. Community pasture management involves application of technologies, land …

Nutrient Movements Through Ruminant Livestock Production Systems, Adegbola T. Adesogan, Jose C. B. Dubeux, Lynn E. Sollenberger

IGC Proceedings (1977-2023)

Considerable attention has been paid to reducing nutrient emissions from ruminant livestock in the last few decades. This area will continue to attract considerable research in the future due to increasing farm sizes in some developed countries as well as the increasing demand for meat and dairy products, particularly in developing countries. This paper discusses the deposition and losses of carbon and nitrogen in soils and plants in grazed and harvested forage systems as well as utilization and losses of both nutrients by ruminants in both systems. The paper also outlines several soil, plant, and animal-focused strategies that can be …

Rainwater Harvesting And Its Impact On Farming Systems, J. S. Samra

IGC Proceedings (1977-2023)

Landless, small holders and other poors supplement their livelihood and adapt to climate change by grazing, stall feeding with crop residues and fodder cultivated under rainfed and irrigated conditions. Improving productivity by conserving rainfall, ground water recharging, harvesting and recycling of rainwater especially in degraded open access or shared land with community participation was quite successful over a wide range of precipitation and ecological situations. Various types of trenches, bunding, vegetative barriers, gully plugs, ponds, check dams, land slides and mine spoils stabilization etc. retained more soil moisture, seeds, vegetative propagules etc. in situ and prevented soil erosion. It regenerated …

Strengthening Livelihood Of Rural Farmer Populations Through Improved Grasslands, Sujatha Premaratne, S. C. Somasiri

IGC Proceedings (1977-2023)

This paper reviews the current background of the grassland resource with a purpose of livestock perspective to improve the livelihood of rural farmers. The use of grasslands for livestock rearing by rural farmers has been a long tradition. In climate and vegetation contrast, these grasslands are much more diverse. They are likely to play an economical role in increasing the milk production in many Asian countries. With an increase of human population, the traditional feeding, breeding and surviving habitats for livestock have been acutely restricted in many countries. Therefore, a continued effort is needed to maintain production for sustainable management …

Problems And Prospects Of Grassland Development: Policy Issues, S. Ray Smith

IGC Proceedings (1977-2023)

There are a range of government and non-government policies that affect grassland development around the world. The objective of this paper is to provide examples of successful policies which have been instrumental in the preservation and maintenance of grasslands and to highlight policies which have resulted in negative consequences. This paper will not attempt to provide a complete overview of policies, but instead will provide examples from representative countries. Policies which affect grasslands can be classified into two broad categories: government policies that cover comprehensive landscape issues like the Grassland Household Contract System (GHCS) in China or the Federal Land …

Management Of Grazing Lands Through Educating Communities, D. Ariungerel, Graeme Hand, Annabel Walsh

IGC Proceedings (1977-2023)

The Mongolian steppe is one of the world’s largest grassland and it is an arid to semiarid land with a strong climate gradient. Biodiversity loss leading to desertification and land degradation is estimated to be impacting around 65% of the total area of Mongolia. The preliminary objective of this project was to trial the Positive Deviance Methodology to determine if this method assists herders to design behaviors to reverse this biodiversity loss. This project is a partnership between Mongolian Herders, Mongolian rangeland scientists and Australian based Stipa Native Grasses Association. The Positive Deviance Methodology has five basic steps based around …

Livestock And Local Development: Going To A New Humananimal Relationship, Jean François Tourrand, Laurent Dobremez, Benoit Dedieu, Guillaume Duteurtre, M. G. Piketty, P. Lescoat, B. Hubert

IGC Proceedings (1977-2023)

Along the past ten years, the French National Agency for Research (ANR) has financed projects regarding livestock. Results of five projects were gathered to understand the long-term livestock trends. At the end of the 19th century, animal breeding was oriented towards the production of goods to meet the local, regional, national and global demand, according to the zone. The market gradually became the key-factor to norm both production and consumption. It is now integrating environmental norms and is starting to invest in the social domain. However, this economical vision of animal production does not take into account the other functions …