Agronomy and Crop Sciences Commons^™

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 …

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 …

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

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

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 …

Animal And Pasture Responses To Grazing Management Of Chemically Suppressed Tall Fescue In Mixed Pastures, Jessica A. Williamson

Theses and Dissertations--Plant and Soil Sciences

Treatment of endophyte-infected tall fescue [Lolium arundinaceum (Schreb.) Darbysh] with the broad leaf herbicide Chaparral® can mitigate fescue toxicosis and enhance forage quality by suppressing seedhead emergence. Applying the herbicide to fescue pastures also reduces forage mass and promotes severe spot grazing when pastures are continuously grazed. A grazing experiment was conducted with steers (2013) and heifers (2014) to evaluate animal and plant responses in fescue-bluegrass (Poa pratensis L.) mixtures treated with Chaparral to determine the effects of grazing management on pasture carrying capacity, nutritive values, botanical composition, and animal performance. Continuous and rotational (i.e., four subdivisions to …

Identification Of Novel Qtl Governing Root Architectural Traits In An Interspecific Soybean Population, Lakshmi P. Manavalan, Silvas J. Prince, Theresa A. Musket, Julian Chaky, Rupesh Deshmukh, Tri D. Vuong, Li Song, Perry B. Cregan, James C. Nelson, J. Grover Shannon, James E. Specht, Henry T. Nguyen

Department of Agronomy and Horticulture: Faculty Publications

Cultivated soybean (Glycine max L.) cv. Dunbar (PI 552538) and wild G. soja (PI 326582A) exhibited significant differences in root architecture and root-related traits. In this study, phenotypic variability for root traits among 251 BC₂F₅ backcross inbred lines (BILs) developed from the cross Dunbar/PI 326582A were identified. The root systems of the parents and BILs were evaluated in controlled environmental conditions using a cone system at seedling stage. The G. max parent Dunbar contributed phenotypically favorable alleles at a major quantitative trait locus on chromosome 8 (Satt315-I locus) that governed root traits (tap root length and …

Genetic And Molecular Characterization Of Submergence Response Identifies Subtol6 As A Major Submergence Tolerance Locus In Maize, Malachy T. Campbell, Christopher A. Proctor, Yongchao Dou, Aaron J. Schmitz, Piyaporn Phansak, Greg R. Kruger, Chi Zhang, Harkamal Walia

Department of Agronomy and Horticulture: Faculty Publications

Maize is highly sensitive to short term flooding and submergence. Early season flooding reduces germination, survival and growth rate of maize seedlings. We aimed to discover genetic variation for submergence tolerance in maize and elucidate the genetic basis of submergence tolerance through transcriptional profiling and linkage analysis of contrasting genotypes. A diverse set of maize nested association mapping (NAM) founder lines were screened, and two highly tolerant (Mo18Wand M162W) and sensitive (B97 and B73) genotypes were identified. Tolerant lines exhibited delayed senescence and lower oxidative stress levels compared to sensitive lines. Transcriptome analysis was performed on these inbreds to provide …

Allmaps: Robust Scaffold Ordering Based On Multiple Maps, Haibo Tang, Xingtan Zhang, Chenyong Miao, Jisen Zhang, Ray Ming, James C. Schnable, Patrick S. Schnable, Eric Lyons, Jianguo Lu

Department of Agronomy and Horticulture: Faculty Publications

The ordering and orientation of genomic scaffolds to reconstruct chromosomes is an essential step during de novo genome assembly. Because this process utilizes various mapping techniques that each provides an independent line of evidence, a combination of multiple maps can improve the accuracy of the resulting chromosomal assemblies. We present ALLMAPS, a method capable of computing a scaffold ordering that maximizes colinearity across a collection of maps. ALLMAPS is robust against common mapping errors, and generates sequences that are maximally concordant with the input maps. ALLMAPS is a useful tool in building high-quality genome assemblies. ALLMAPS is available at: https://github.com/tanghaibao/jcvi/wiki/ALLMAPS.

Effects Of Sowing Date On Phenotypic Plasticity Of Fitness-Related Traits In Two Annual Weeds On The Songnen Plain Of China, Haiyan Li, John L. Lindquist, Yunfei Yang

Department of Agronomy and Horticulture: Faculty Publications

Background Phenotypic plasticity of fitness-related traits is vital for plant species to adapt to variable environments. Chenopodium glaucum L. and Amaranthus retroflexus L. are two common weed species globally. Understanding the plasticity in life-history traits, especially in reproductive allocation, within and among these species is important for predicting their success and for managing them in different environments.

Methodology/Principal Findings Seeds of the two plant species were sown every 10 days from 26 Jun to 15 Aug. Life-history and fitness-related traits of both phenology and morphology were measured, and dry biomass of roots, stems, leaves, and reproductive tissues was determined at …

Fingerprinting Soybean Germplasm And Its Utility In Genomic Research, Qijian Song, D. L. Hyten, Gaofeng Jia, Charles V. Quigley, Edward W. Fickus, Randall L. Nelson, P. B. Cregan

Department of Agronomy and Horticulture: Faculty Publications

The United States Department of Agriculture, Soybean Germplasm Collection includes 18,480 domesticated soybean and 1,168 wild soybean accessions introduced from 84 countries or developed in the U.S. This collection was genotyped with the SoySNP50K BeadChip containing greater than 50K SNPs. Redundant accessions were identified in the collection and distinct genetic backgrounds of soybean from different geographic origins were observed that could be a unique resource for soybean genetic improvement. We detected a dramatic reduction of genetic diversity based on linkage disequilibrium and haplotype structure analyses of the wild, landrace and North American cultivar populations and identified candidate regions associated with …

Selective Genotyping For Marker Assisted Selection Strategies For Soybean Yield Improvement, Benjamin D. Fallen, Fred L. Allen, Dean A. Kopsell, Arnold M. Saxton, Leah Mchale, J. Grover Shannon, Stella K. Kantartzi, Andrea J. Cardinal, P. B. Cregan, D. L. Hyten, Vincent R. Pantalone

Department of Agronomy and Horticulture: Faculty Publications

Using molecular markers in soybean [Glycine max (L.) Merr.] has lead to the identification of major loci controlling quantitative and qualitative traits that include: disease resistance, insect resistance and tolerance to abiotic stresses. Yield has been considered as one of the most important quantitative traits in soybean breeding. Unfortunately, yield is a very complex trait and most yield quantitative trait loci (QTL) that have been identified have had only limited success for marker assisted selection (MAS). The objective of this study was to identify QTL associated with soybean seed yield in preliminary yield trials grown in different environments and …

Qtl For Seed Protein And Amino Acids In The Benning × Danbaekkong Soybean Population, C. V. Warrington, H. Abdel‑Haleem, D. L. Hyten, P. B. Cregan, J. H. Orf, A. S. Killam, N. Bajjalieh, Z. Li, H. R. Boerma

Department of Agronomy and Horticulture: Faculty Publications

Soybean, rather than nitrogen-containing forages, is the primary source of quality protein in feed formulations for domestic swine, poultry, and dairy industries. As a sole dietary source of protein, soybean is deficient in the amino acids lysine (Lys), threonine (Thr), methionine (Met), and cysteine (Cys). Increasing these amino acids would benefit the feed industry. The objective of the present study was to identify quantitative trait loci (QTL) associated with crude protein (cp) and amino acids in the ‘Benning’ × ‘Danbaekkong’ population. The population was grown in five southern USA environments. Amino acid concentrations as a fraction of cp (Lys/cp, Thr/cp, …