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Full-Text Articles in Agricultural Science

Importance Of Livestock Production From Grasslands For National And Local Food And Nutritional Security In Developing Countries, Iain A. Wright Jan 2015

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 Jan 2015

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 6th, 7th, and 8th selection cycles. All UK populations were more 2,4-D tolerant than Kenland. The 2,4-D tolerance following the 6th 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 …


Production, Persistence And Diversity Of Species In Temperate Grasslands, Meredith L. Mitchell, Brendan P. Christy Jan 2015

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 Jan 2015

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 Jan 2015

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 Jan 2015

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 Jan 2015

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 Jan 2015

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 Jan 2015

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 Jan 2015

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 Jan 2015

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 …


Genomic Approaches For Dissecting Complex Traits Related To Quality Production Of Range Grasses, Masumi Ebina Jan 2015

Genomic Approaches For Dissecting Complex Traits Related To Quality Production Of Range Grasses, Masumi Ebina

IGC Proceedings (1977-2023)

Tropical grasses have been widely used as warm-season forage grasses in the warm temperate zone since the early 20th century because of their high yields; they have also been used as perennial forages in their native tropical areas. Increasing demand for animal production sparked by economic development in tropical countries is requiring breeders to improve native forage grasses in these countries. Considerable efforts have been made to breed accessions with improved characteristics and to develop new cultivars. However, cross-breeding is not common, owing to a lack of genetic information and to complexities related to polyploidy, high sterility rates, outcrossing, and …


Emission Of Green House Gases From Grasslands And Their Mitigation, Prem N. Sharma, Shyam Khadka Jan 2015

Emission Of Green House Gases From Grasslands And Their Mitigation, Prem N. Sharma, Shyam Khadka

IGC Proceedings (1977-2023)

The concentrations of green house gases (GHG) in the atmosphere began in pre-industrial times and it continues to increase. This could result into an alarming increase in temperature of up to 5.4 oC by year 2100 due to a net global annual GHG emission of H 4.5-6.5 Gt C equivalent. About 18% of the world’s GHG are contributed by livestock and related activities on grasslands that are spread over almost 35 million Km2.These grasslands give livelihood to over a billion people most of who are poor. Twenty to 70% of the land surface area is degrading often …


High-Altitude Grassland Management And Improvement Of Pastoral Livelihoods In The Hindu Kush Himalayan Region, Eklabya Sharma Jan 2015

High-Altitude Grassland Management And Improvement Of Pastoral Livelihoods In The Hindu Kush Himalayan Region, Eklabya Sharma

IGC Proceedings (1977-2023)

The Hindu Kush Himalayan (HKH) region is the largest mountain systems in the world, spanning over 4.3 million km2 and covering 3500 km long fragile environment. Grasslands in the HKH region are the source of livelihoods for approximately 25 to 30 million pastoralists and agro-pastoralists. High altitude grasslands play a significant role in storage and regulation of water; storage of carbon in soil and peat lands; permafrost storage; and stabilization of climate, soil, and nutrients. They foster a rich biodiversity with endemic species of fauna and flora; provide clean air and open spaces for recreational purposes, and bolster a rich …


Xrf Analyses Of Prehanford Orchards, Komal Rana Aug 2014

Xrf Analyses Of Prehanford Orchards, Komal Rana

STAR Program Research Presentations

Subsequent to 1943, the use of Lead Arsenic was banned from the Orchards standing on the Hanford site. This use of Lead Arsenate pesticide was popular among the orchard owners and was dispersed over the site in a myriad of ways. The presence of the traces of lead and arsenic are found today, more than half a century later. Using a portable X-ray florescence analyzer (XRF), the values of lead and arsenic are evaluated while determining the efficiency of the equipment itself. Samples from different decision sites were collected, with lead arsenic values in the low, high and medium range …


Glyphosate Resistant Weeds - Beat Them Before They Beat You, Sally Peltzer Jan 2014

Glyphosate Resistant Weeds - Beat Them Before They Beat You, Sally Peltzer

Grain and other field crops published reports

Herbicide resistance develops if the weeds exist in the population and set fertile seed. Being vigilant, keeping weed populations low and stopping seed set is the best way to prevent glyphosate resistance development:

  • know the herbicide use history of each paddock. If glyphosate has been the dominant knockdown and spray-topping product used, it's time to change
  • conduct herbicide resistance testing to determine what herbicides are effective on key weeds
  • aim for maximum control
  • establish a more diverse rotation to increase the number of control tactics available
  • use non-herbicide control tactics at every opportunity
  • always monitor the success of each control …


Development Of An Optical Sensor For Real-Time Weed Detection Using Laser Based Spectroscopy, Arie Jacobus Paap Jan 2014

Development Of An Optical Sensor For Real-Time Weed Detection Using Laser Based Spectroscopy, Arie Jacobus Paap

Theses: Doctorates and Masters

The management of weeds in agriculture is a time consuming and expensive activity, including in Australia where the predominant strategy is blanket spraying of herbicides. This approach wastes herbicide by applying it in areas where there are no weeds. Discrimination of different plant species can be performed based on the spectral reflectance of the leaves. This thesis describes the development of a sensor for automatic spot spraying of weeds within crop rows. The sensor records the relative intensity of reflected light in three narrow wavebands using lasers as an illumination source.

A prototype weed sensor which had been previously developed …


Distribution And Control Of Glyphosate-Resistant Johnsongrass (Sorghum Halepense) In Arkansas Soybean, Dennis Brent Johnson Aug 2013

Distribution And Control Of Glyphosate-Resistant Johnsongrass (Sorghum Halepense) In Arkansas Soybean, Dennis Brent Johnson

Graduate Theses and Dissertations

Johnsongrass, once the most persistent and troublesome grass weed of row crops throughout the southern U.S., has previously been confirmed resistant to the acetolactate synthase (ALS) and acetyl-coenzyme A carboxylase-inhibiting herbicides in the Midsouth and has recently evolved resistance to glyphosate in Arkansas. The goal of this research was to establish the geographical distribution of herbicide-resistant johnsongrass in Arkansas and to develop herbicide programs for controlling glyphosate-resistant johnsongrass in Arkansas soybean. Johnsongrass accessions were collected from 14 counties in the Mississippi River Delta region of Arkansas and screened for resistance to four of the most commonly used postemergence herbicides for …


Genetic Diversity Of Seed Dormancy And Molecular Evolution Of Weedy Red Rice, Te Ming Tseng May 2013

Genetic Diversity Of Seed Dormancy And Molecular Evolution Of Weedy Red Rice, Te Ming Tseng

Graduate Theses and Dissertations

Rice is the grain with the third-highest global production. In the US, Arkansas is the largest rice producing state; however, an estimated 62% of the rice fields in the state are infested with red rice, and can cause up to 80% yield reduction in rice. Among its weedy traits, seed dormancy plays an important role in its persistence, and helps red rice escape weed management techniques thereby increasing the red rice soil seedbank. Red rice also has the potential to hybridize among themselves and with cultivated rice, thus resulting in diverse phenotypes and genotypes. In this study we measured variation …


Glyphosate-Resistant Palmer Amaranth (Amaranthus Palmeri) In Arkansas: Resistance Mechanisms And Management Strategies, Griff Michael Griffith May 2013

Glyphosate-Resistant Palmer Amaranth (Amaranthus Palmeri) In Arkansas: Resistance Mechanisms And Management Strategies, Griff Michael Griffith

Graduate Theses and Dissertations

Since 2000, there have been thirteen weed species confirmed resistant (R) to glyphosate in the United States, six of those resistant species are present in Arkansas. The goal of this research was to confirm and to determine the level of resistance in two R Palmer amaranth biotypes from Mississippi (MC-R) and Lincoln (LC-R) Counties, Arkansas, and one susceptible (S) biotype from Clarendon County, South Carolina, which had never been exposed to glyphosate. Shikimic acid concentration over time was significantly greater in the S biotype than both the MC-R and LC-R biotypes. The lethal dose required to kill 50% (LD50 …


Sorghum Transformation: Overview And Utility, Tejinder Kumar, Arlene Howe, Shirley Sato, Ismail M. Dweikat, Tom E. Clemente Jan 2013

Sorghum Transformation: Overview And Utility, Tejinder Kumar, Arlene Howe, Shirley Sato, Ismail M. Dweikat, Tom E. Clemente

Department of Agronomy and Horticulture: Faculty Publications

Over the past decade genomics resources available for sorghum have rapidly expanded (Paterson Int J Plant Genomics 2008:6, 2008), these resources, coupled with the recent completion of the genome sequence which is relatively small in size (730 Mb) (Paterson et al. Nature 457:551–556, 2009) makes sorghum a rather attractive species to study. Moreover, the USDA germplasm system maintains 42,614 accessions, of which more than 800 exotic landraces have been converted to day length-insensitive lines to facilitate their use in breeding programs. In addition, a set of EMS mutation stocks developed by the USDA Plant Stress and Germplasm Development Unit in …


Documentation And Control Of Acetolactate Synthase-Resistant Barnyardgrass (Echinochloa Crus-Galli) In Arkansas Rice, Michael Joshua Wilson Dec 2012

Documentation And Control Of Acetolactate Synthase-Resistant Barnyardgrass (Echinochloa Crus-Galli) In Arkansas Rice, Michael Joshua Wilson

Graduate Theses and Dissertations

Barnyardgrass, the most problematic grass weed of Arkansas rice, was found resistant to propanil in 1990, and since then, it has evolved resistance to quinclorac and clomazone. Barnyardgrass is now believed to have evolved resistance to acetolactate synthase (ALS)-inhibiting herbicides. The goal of this research was to confirm and determine the level of resistance of the putative resistant biotype to the ALS-inhibiting herbicides imazethapyr, bispyribac, and penoxsulam and to develop herbicide programs for controlling ALS-, propanil-, quinclorac-, and clomazone-resistant barnyardgrass. The lethal dose needed to kill 50% of the putative ALS-resistant plants was higher than that of the susceptible biotype …


Situation Statement: The 'Prickle Bush' Weeds (Mesquite, Parkinsonia And Prickly Acacia) In Western Australia, Jon Dodd, Andrew Reeves, Richard Watkins, Linda Anderson Nov 2012

Situation Statement: The 'Prickle Bush' Weeds (Mesquite, Parkinsonia And Prickly Acacia) In Western Australia, Jon Dodd, Andrew Reeves, Richard Watkins, Linda Anderson

Biosecurity published reports

The term 'Prickle bush weeds' refers to weedy trees and shrubs of Mesquite, Parkinsonia and Prickly acacia. All are present in Western Australia.

Mesquite and Parkinsonia are widespread, well established woody weeds in various parts of the WA Rangelands. Prickly acacia is a recent introduction and has a relatively restricted distribution in the East Kimberley. All three impact mainly on the pastoral industry and have considerable potential for further spread and greater impact within the Rangelands. All are Weeds of National Significance (WoNS) and are high priority Declared Plants in WA.

The purpose of this situation statement is to describe …


Weed Science Research Summaries 2011, K. L. Smith, J. A. Bullington, R. C. Doherty, J. R. Meier May 2012

Weed Science Research Summaries 2011, K. L. Smith, J. A. Bullington, R. C. Doherty, J. R. Meier

Arkansas Agricultural Experiment Station Research Series

No abstract provided.


Herbicide Resistance Mechanism(S) In Italian Ryegrass (Lolium Perenne Ssp. Multiflorum) Populations In The Southern United States, Reiofeli Algodon Salas May 2012

Herbicide Resistance Mechanism(S) In Italian Ryegrass (Lolium Perenne Ssp. Multiflorum) Populations In The Southern United States, Reiofeli Algodon Salas

Graduate Theses and Dissertations

Italian ryegrass is a principal weed problem in wheat production fields in the Southern US. Resistance to herbicides diclofop, mesosulfuron, and pinoxaden among ryegrass populations has been reported. Glyphosate-resistant Italian ryegrass populations were identified in Desha County, Arkansas. This research aimed to 1) determine resistance patterns to ACCase (diclofop and pinoxaden) and ALS (imazamox, mesosulfuron, and pyroxsulam) herbicides among Italian ryegrass populations from the southern US; 2) determine if cytochrome P450-mediated enhanced herbicide metabolism contributed to resistance; and 3) elucidate the resistance mechanism to glyphosate in four Arkansas populations (Des03, Des05, Des14, and D8). For objective 1, 30 accessions from …


Superweeds And Suspect Seeds: Does The Genetically-Engineered Crop Deregulation Process Put American Agriculture At Risk, Margaret Sova Mccabe Jan 2012

Superweeds And Suspect Seeds: Does The Genetically-Engineered Crop Deregulation Process Put American Agriculture At Risk, Margaret Sova Mccabe

Law Faculty Scholarship

The federal government’s regulatory approach to genetically engineered (GE) crops, known as “The Framework”, is now twenty-five years old. Despite two and half decades of a consistent regulatory regime, GE crop and food regulation remains controversial. This article suggests that regulatory science and its tenets of independence, transparency, and public science should guide reforms of The Framework so that it is an efficient and reliable regulatory system. The article has four parts: 1) it provides a brief overview of the history of GE crop regulation; 2)it describes the key attributes of The Framework and related regulatory documents, with particular focus …


Weed Science Research Summaries 2010, K. L. Smith, J A. Bullington, R. C. Doherty, J. R. Meier Oct 2011

Weed Science Research Summaries 2010, K. L. Smith, J A. Bullington, R. C. Doherty, J. R. Meier

Arkansas Agricultural Experiment Station Research Series

No abstract provided.


Increased Weed Diversity, Density And Above-Ground Biomass In Long-Term Organic Crop Rotations, Samuel E. Wortman, John L. Lindquist, Milton J. Haar, Charles A. Francis Jan 2010

Increased Weed Diversity, Density And Above-Ground Biomass In Long-Term Organic Crop Rotations, Samuel E. Wortman, John L. Lindquist, Milton J. Haar, Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

While weed management is consistently a top priority among farmers, there is also growing concern for the conservation of biodiversity. Maintaining diverse weed communities below bioeconomic thresholds may provide ecosystem services for the crop and the surrounding ecosystem. This study was conducted to determine if weed diversity, density and biomass differ within and among organic and conventional crop rotations. In 2007 and 2008, we sampled weed communities in four long-term crop rotations near Mead, Nebraska, United States using seedbank analyses (elutriation and greenhouse emergence) and above-ground biomass sampling. Two conventional crop rotations consisted of a corn (Zea mays) …


Managing Glyphosate-Resistant Horseweed In Arkansas Cotton 2004, Ronald E. Talbert, Marilyn R. Mcclelland, James L. Barrentine, Kenneth L. Smith, Monica B. Kelley Oct 2005

Managing Glyphosate-Resistant Horseweed In Arkansas Cotton 2004, Ronald E. Talbert, Marilyn R. Mcclelland, James L. Barrentine, Kenneth L. Smith, Monica B. Kelley

Arkansas Agricultural Experiment Station Research Series

No abstract provided.


Field Evaluation Of Herbicides On Vegetables And Small Fruits 2004, Ronald E. Talbert, Colleen M. Thomas, Brian V. Ottis, Andrew T. Ellis May 2005

Field Evaluation Of Herbicides On Vegetables And Small Fruits 2004, Ronald E. Talbert, Colleen M. Thomas, Brian V. Ottis, Andrew T. Ellis

Arkansas Agricultural Experiment Station Research Series

Herbicide evaluation studies on vegetables and small fruits were conducted in 2004 at the Arkansas Agricultural Experiment Station at Fayetteville, AR, in an effort to evaluate new herbicides, herbicide mixtures, and their application timings for weed control efficacy and crop tolerance. Results of these studies, in part, provide useful information to producers, fellow researchers, the Crop Protection Industry, and the IR-4 Minor Crop Pest Management Program in the development of potential new herbicide uses in vegetable, and fruit.