Agriculture Commons^™

Cell Wall Peptidolipids Of Mycobacterium Avium: From Genetic Prediction To Exact Structure Of A Nonribosomal Peptide, John Bannantine, Giles Etienne, Francoise Laval, Judith R. Stabel, Anne Lemassu, Mamadou Daffe, Darrell O. Bayles, Christelle Ganneau, Frederic Bonhomme, Maxime Branger, Thierry Cochard, Sylvie Bay, Franck Biet

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Mycobacteria have a complex cell wall structure that includes many lipids; however, even within a single subspecies of Mycobacterium avium these lipids can differ. Total lipids from an M. avium subsp. paratuberculosis (Map) ovine strain (S-type) contained no identifiable glycopeptidolipids or lipopentapeptide (L5P), yet both lipids are present in other M. avium subspecies. We determined the genetic and phenotypic basis for this difference using sequence analysis as well as biochemical and physico-chemical approaches. This strategy showed that a nonribosomal peptide synthase, encoded by mps1, contains three amino acid specifying modules in ovine strains, compared to five modules in bovine strains …

The Future Of Blackbird Management Research, Page E. Klug

United States Department of Agriculture Wildlife Services: Staff Publications

Human society values birds for their intrinsic and aesthetic value as well as the ecosystem services they provide as pollinators, consumers of pests, and distributors of nutrients and seeds (Wenny et al. 2011). At the same time, conflict between birds and humans is an age-old phenomenon that has persisted as society has transformed and the scale of agriculture has expanded (Conover 2002). Managing conflict between birds and agriculture is challenging for many reasons. Foremost, the need to consider both human welfare and conservation of protected bird species is paramount, with nonlethal management methods preferred to lethal measures from societal, economical, …

Strategies For Evading Blackbird Damage, George M. Linz, Page E. Klug

United States Department of Agriculture Wildlife Services: Staff Publications

Foraging blackbird flocks have great mobility as they search for food that is plentiful, is easily accessed, and has a high nutritional value. Ripening corn, rice, and sunflower fit those criteria, as does seeded rice. The birds will move from field to field to find the ideal combination of energy spent to discover food versus the energy value of the food (Pyke et al. 1977). An extraordinary effort is often needed to actively move the birds from a foraging location with a high positive value (e.g., close to roost and early ripening sunflower) versus a location with a I~w value …

Meat For Missoula: Educating Our Youth On Sustainable Meat Production Practices, Amelia R G Liberatore

Undergraduate Theses, Professional Papers, and Capstone Artifacts

In autumn 2016, a controversy arose when a student group, Advocates for Animals, took up a campaign against three meat pigs at the PEAS Farm due to strong views about animal consumption. Pigs serve as a central piece of food source education to hundreds of Missoula children who visit the farm every year. Unfortunately, the controversy overshadowed the educational purpose of exposing children to sustainable meat production practices. Moreover, access to the PEAS Farm and good food education is not available to all local children. I wondered whether education was accessible elsewhere. Unfortunately, child-appropriate, culturally relevant food literature is scarce. …

Opuntioid Cacti Management Guide: Best Practice Information For Austrocylindropuntia, Cylindropuntia And Opuntia Species In Australia, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity published reports

Key points:

• Australia does not have any native cacti.
• Opuntioid cacti impact on Australia environmentally, agriculturally and aesthetically, as well as posing a risk to animal welfare and human safety.
• Invasive cacti are drought resistant and hardy, surviving in low rainfall environments.
• All species spread vegetatively through the rooting of cladodes (stem segments), fruits or flowers. Some species also spread by seed.
• Opuntioid cacti vary significantly in their form and habit, ranging from low-growing shrubs under 50 cm to erect trees up to approximately 6 m tall.
• Australian rangelands are especially vulnerable to cacti invasion.
• The cost of control often …

Education And The Development Of On-Farm Identity: Dairy Farm Women's Experiences, Amy Leigh Spangenberg

Walden Dissertations and Doctoral Studies

Women throughout the world have found emancipation through education. Yet, there has been no research on the role that education plays in dairy farm women's primary, on-farm identity development and how farm women's identities develop. The purpose of this phenomenological study was to examine dairy farm women's perceptions of previous learning (education) and its influence on their primary, on-farm identity development. The feminist standpoint theory provided the framework for this study. A homogeneous, purposeful sample of 10 active dairy farm women were interviewed using individual, face to face, semistructured questions to answer the question: What are dairy farm women's perceptions …

Relationship Between The California Drought And Almond Demand, Wayne E. Lacy

Walden Dissertations and Doctoral Studies

Areas of California's Central Valley are sinking at rates up to 1 foot per year due to subsidence caused, in part, by the state's years-long drought, challenging growers to locate additional water sources for their crops. Supply and demand theory guided this correlational study. The purpose of the study was to examine the financial impact of drought on almond demand. This study included annualized historical almond industry data for the United States (N = 97), downloaded from a United States Department of Agriculture database. The results of multiple linear regression analysis indicated that the model was capable of predicting almond …

Regeneration And Invasion Of Cottonwood Riparian Forest Following Wildfire, Carissa L. Wonkka, Dirac L. Twidwell Jr., Christine H. Bielski, Craig R. Allen, Michael C. Stambaugh

Department of Agronomy and Horticulture: Faculty Publications

Populus deltoides is considered to be a weak resprouter and highly susceptible to wildfire, but few post-wildfire studies have tracked P. deltoides response and resprouting within the Great Plains of North America. Following a wildfire in southwestern Kansas, U.S.A., we surveyed burned and unburned areas of a cottonwood riparian forest along the Cimarron River that included a major understory invader, tamarisk (Tamarix ramosissima Ledeb.). We tested the following hypotheses, which are consistent with the current understanding of P. deltoides response to wildfire in the Great Plains: (1) regeneration of P. deltoides will be low in areas burned by the …

Assessment Of Canopy Chlorophyll Content Retrieval In Maize And Soybean: Implications Of Hysteresis On The Development Of Generic Algorithms, Yi Peng, Anthony L. Nguy-Robertson, Timothy J. Arkebauer, Anatoly A. Gitelson

Department of Agronomy and Horticulture: Faculty Publications

Canopy chlorophyll content (Chl) closely relates to plant photosynthetic capacity, nitrogen status and productivity. The goal of this study is to develop remote sensing techniques for accurate estimation of canopy Chl during the entire growing season without re-parameterization of algorithms for two contrasting crop species, maize and soybean. These two crops represent different biochemical mechanisms of photosynthesis, leaf structure and canopy architecture. The relationships between canopy Chl and reflectance, collected at close range and resampled to bands of the Multi Spectral Instrument (MSI) aboard Sentinel-2, were analyzed in samples taken across the entirety of the growing seasons in three irrigated …

Caseous Lymphadenitis Management In Goats, C. Kim Chapman, Matthew J. Kennedy

All Current Publications

This fact sheet describes Caseous Lymphadenitis, an infectious disease of sheep and goats and gives information on managing the disease.

Southeastern Utah Small-Scale Mixed Vegetable Production Costs And Returns - 2 Acres, 2016, Kynda Curtis, Jacob Rudd

All Current Publications

Sample costs and returns to produce mixed vegetables under drip irrigation and sold through direct markets in Southeastern Utah are presented. This publication is intended to be a guide used to make production decisions, determine potential returns and prepare business and marketing plans.

Goldfields Nullarbor Rangelands Biosecurity Association Inc. Activity Report 2016/17, Goldfields Nullarbor Rangelands Biosecurity Association Inc.

Recognised Biosecurity Group Annual Reports

The Goldfields Nullarbor Rangelands Biosecurity Association Inc. (GNRBA) is unique in rangeland management across Western Australia. It has a huge area to service and is working hard to provide a top class service to ratepayers. It is now well recognised as being a leader in the RBG’s in WA. The GNRBA Inc formally became operational on 1st July 2011. At this time it took over the APB Zone 9 operations.

Kimberley Rangelands Biosecurity Association Invasive Species Activity Report 2016/17, Kimberley Rangelands Biosecurity Association

Recognised Biosecurity Group Annual Reports

The Kimberley Rangelands Biosecurity Association (KRBA) has an annual Large Feral Herbivore culling program that includes feral donkeys, horses and camels with other animals such as water buffalo and pigs targeted when located. The program focusses primarily on donkeys, using the radio telemetry technique with horses and camels culled opportunistically during tracking. Currently there are 135 active collars throughout the region.

Meekatharra Rangelands Biosecurity Association Inc. Annual Report 2016/17, Meekatharra Rangelands Biosecurity Association Inc.

Recognised Biosecurity Group Annual Reports

The Meekatharra Rangelands Biosecurity Association Inc (MRBA) is an industry body with a membership of all pastoralists in the Shires of Yalgoo, Mount Magnet, Cue and Meekatharra. The Association has been established under the Biosecurity and Agriculture Management Act 2007 with a charter to manage and control declared pests, both animal and plant.

Pilbara Regional Biosecurity Group Inc. Annual Report 2016/17, Pilbara Regional Biosecurity Group Inc.

Recognised Biosecurity Group Annual Reports

The Pilbara RBG is a not for profit association formed under the Associations Incorporation Act 2015, providing declared pest control programs for land managers, particularly in the pastoral zone. The associations’ primary purpose is the control of declared pests using funding from Declared Pest Rates paid by landholders on pastoral stations. These Declared Pest Rates funds are matched dollar for dollar by the WA Government to reflect the public benefit of controlling declared pest animals and weeds. The association is formally recognised by the Hon Minister for Agriculture and Food as a recognised biosecurity group (RBG).

Using Exogenous Hormone Application To Suppress Axillary Shoot Development In Tobacco, W. Jesse Carmack

Theses and Dissertations--Plant and Soil Sciences

The variability in the number of basal axillary shoots (ground suckers) among all tobacco (Nicotiana tabacum L.) varieties, has increased since the hydroponic transplant production system became the standard. The larger root ball of hydroponically produced transplants compared to traditionally produced transplants potentially generates a difference in the ratio of auxin (inhibits axillary shoot formation) to cytokinin (promotes lateral branching), that induces basal axillary shoot development. Starting in 2014, studies were conducted to investigate whether the addition of synthetic auxins or cytokinins to hydroponic transplant production could prevent ground sucker formation. Different tobacco cultivars, with high or low ground sucker …

Influence Of Tillage On Common Ragweed (Ambrosia Artemisiifolia) Emergence Pattern In Nebraska, Ethann R. Barnes, Rodrigo Werle, Lowell Sandell, John L. Lindquist, Stevan Z. Knezevic, Peter H. Sikkema, Amit J. Jhala

Department of Agronomy and Horticulture: Faculty Publications

Spring tillage is a component of an integrated weed management strategy for control of early emerging glyphosate-resistant weeds such as common ragweed; however, the effect of tillage on common ragweed emergence pattern is unknown. The objectives of this study were to evaluate whether spring tillage during emergence would influence the emergence pattern or stimulate additional emergence of common ragweed and to characterize common ragweed emergence in southeast Nebraska. A field experiment was conducted for three years (2014 to 2016) in Gage County, Nebraska in a field naturally infested with glyphosate-resistant common ragweed. Treatments consisted of a no-tillage control and three …

Can Yield Gap Analysis Be Used To Inform R & D Prioritisation?, P. A. J. Van Oort, K. Saito, I. Dieng, P. Grassini, K. G. Cassman, M. K. Van Ittersum

Department of Agronomy and Horticulture: Faculty Publications

The phrase “biggest bang for a buck” is associated with the policy making question that governments and development agencies face: “Where and which crops should receive highest priority for improving local and global food supply?”. A first step of prioritisation is to identify region x crop combinations for which high impact can be anticipated. We developed a new method for this prioritisation exercise and applied it to data from the Global Yield Gap and Water Productivity Atlas (GYGA). Our prioritisation distinguishes between two policy objectives (humanitarian and economic) and builds upon the relative yield gap and climate risk. Results of …

Author Correction: Genome-Guided Phylo-Transcriptomic Methods And The Nuclear Phylogenetic Tree Of The Paniceae Grasses, Jacob D. Washburn, James C. Schnable, Gavin C. Conant, Thomas P. Brutnell, Ying Shao, Yang Zhang, Martha Ludwig, Gerrit Davidse, J. Chris Pires

Department of Agronomy and Horticulture: Faculty Publications

The original version of this Article contained an error in the title of the paper, where the word “Phylogenetic” was incorrectly given as “Phylogentic”. This has now been corrected in the PDF and HTML versions of the Article, and in the accompanying Supplementary Information file.

Lettuce Learn: Student Reflections On Building And Sustaining A Community Donation Garden, Hannah Dankbar, Emily K. Zimmerman, Carrie Chennault, Andrea D. Basche, Jacqueline Ann Nester, Maritza Pierre, Gabrielle Roesch-Mcnally

Department of Agronomy and Horticulture: Faculty Publications

This article emerged from conversations that we and fellow graduate students have had in building a community donation garden. We created the garden with a vision of enacting food justice in our community, but over the past four years we have experienced complexities with our vision. In this article, we share the complexities with which we have wrestled, how we have encouraged thoughtful dialogue among fellow scholars about these shortcomings and the intricate workings of the agrifood system, and the lessons we have learned through these experiences as early-career scholar-activists. This article represents our collective and individual voices as graduate …

Leveraging Agroecology For Solutions In Food, Energy, And Water, Marcia Delonge, Andrea D. Basche

Department of Agronomy and Horticulture: Faculty Publications

Global agriculture is facing growing challenges at the nexus of interconnected food, energy and water systems, including but not limited to persistent food insecurity and diet-related diseases; growing demands for energy and consequences for climate change; and declining water resources, water pollution, floods and droughts. Further, soil degradation and biodiversity loss are both triggers for and consequences of these problems. In this commentary, we argue that expanding agroecological principles, tools, and technologies and enhancing biological diversity can address these challenges and achieve better socioeconomic outcomes. Agroecology is often described as multi- or transdiscplinary, and applies ecological principles to the design …

Using An Active-Optical Sensor To Develop An Optimal Ndvi Dynamic Model For High-Yield Rice Production (Yangtze, China), Xiaojun Liu, Richard B. Ferguson, Hengbiao Zheng, Qiang Cao, Yongchao Tian, Weixing Cao, Yan Zhu

Department of Agronomy and Horticulture: Faculty Publications

The successful development of an optimal canopy vegetation index dynamic model for obtaining higher yield can offer a technical approach for real-time and nondestructive diagnosis of rice (Oryza sativa L) growth and nitrogen (N) nutrition status. In this study, multiple rice cultivars and N treatments of experimental plots were carried out to obtain: normalized difference vegetation index (NDVI), leaf area index (LAI), above-ground dry matter (DM), and grain yield (GY) data. The quantitative relationships between NDVI and these growth indices (e.g., LAI, DM and GY) were analyzed, showing positive correlations. Using the normalized modeling method, an appropriate NDVI simulation model …

Jasmonoyl-L-Tryptophan Disrupts Iaa Activity Through The Aux1 Auxin Permease, Paul E. Staswick, Martha Rowe, Edgar P. Spalding, Bessie L. Splitt

Department of Agronomy and Horticulture: Faculty Publications

Amide-linked conjugates between tryptophan (Trp) and jasmonic (JA) or indole-3- acetic (IAA) acids interfered with gravitropism and other auxin-dependent activities in Arabidopsis, but the mechanism was unclear. To identify structural features necessary for activity several additional Trp conjugates were synthesized. The phenylacetic acid (PAA) conjugate was active, while several others were not. Common features of active conjugates is that they have ring structures that are linked to Trp through an acetic acid side chain, while longer or shorter linkages are inactive or less active. A dominant mutant, called tryptophan conjugate response1-D that is insensitive to JA-Trp, but still sensitive …

Reversing Resistance To Tembotrione In An Amaranthus Tuberculatus (Var. Rudis) Population From Nebraska, Usa With Cytochrome P450 Inhibitors, Maxwel C. Oliveira, Todd A. Gaines, Franck E. Dayan, Eric L. Patterson, Amit J. Jhala, Stevan Z. Knezevic

Department of Agronomy and Horticulture: Faculty Publications

Background: A population of Amaranthus tuberculatus (var. rudis) was confirmed resistant to 4-hydroxyphenylpyruvate dioxygenase (HPPD)-inhibitor herbicides (mesotrione, tembotrione, and topramezone) in a seed corn/soybean rotation in Nebraska. Further investigation confirmed a non-target-site resistance mechanism in this population. The main objective of this study was to explore the role of cytochrome P450 inhibitors in restoring the efficacy of HPPD-inhibitor herbicides on the HPPD-inhibitor resistant A. tuberculatus population from Nebraska, USA (HPPD-R).

Background: A population of Amaranthus tuberculatus (var. rudis) was confirmed resistant to 4-hydroxyphenylpyruvate dioxygenase (HPPD)-inhibitor herbicides (mesotrione, tembotrione, and topramezone) in a seed corn/soybean rotation in Nebraska. Further investigation confirmed …

Tgbs® Genotyping-By-Sequencing Enables Reliable Genotyping Of Heterozygous Loci, Alina Ott, Sanzhen Liu, James C. Schnable, Cheng-Ting 'Eddy' Yeh, Kai-Sin Wang, Patrick S. Schnable

Department of Agronomy and Horticulture: Faculty Publications

Conventional genotyping-by-sequencing (cGBS) strategies suffer from high rates of missing data and genotyping errors, particularly at heterozygous sites. tGBS® genotyping-by-sequencing is a novel method of genome reduction that employs two restriction enzymes to generate overhangs in opposite orientations to which (single-strand) oligos rather than (double-stranded) adaptors are ligated. This strategy ensures that only doubledigested fragments are amplified and sequenced. The use of oligos avoids the necessity of preparing adaptors and the problems associated with inter-adaptor annealing/ligation. Hence, the tGBS protocol simplifies the preparation of high-quality GBS sequencing libraries. During polymerase chain reaction (PCR) amplification, selective nucleotides included at the 3'-end …

Using An Unmanned Aerial Vehicle To Evaluate Nitrogen Variability And Height Effect With An Active Crop Canopy Sensor, Brian Krienke, Richard B. Ferguson, Michael Schlemmer, Kyle Holland, David B. Marx, Kent M. Eskridge

Department of Agronomy and Horticulture: Faculty Publications

Ground-based active sensors have been used in the past with success in detecting nitrogen (N) variability within maize production systems. The use of unmanned aerial vehicles (UAVs) presents an opportunity to evaluate N variability with unique advantages compared to ground-based systems. The objectives of this study were to: determine if a UAV was a suitable platform for use with an active crop canopy sensor to monitor in-season N status of maize, if UAV’s were a suitable platform, is the UAV and active sensor platform a suitable substitute for current handheld methods, and is there a height effect that may be …

Defense And Prosecuting Attorney Perceptions Of Facility Dogs In The Courtroom, Kristy Melissa Donaldson

Walden Dissertations and Doctoral Studies

Attorneys must obtain evidence for purporting their position on a court case. Many factors are considered when working with witness testimony such as age, development, narrative recall, and retraumatization. Research has detailed the hardship of obtaining evidence during witness testimony and the importance of support systems to help with the process. Existing research illustrates the stressors caused by the court processes, witness fear, and difficulty for attorneys to ascertain testimony. Therapeutic animals have been well researched and shown to have an important support role in many professions and situations. Additionally, much has been written regarding the use of varying types …

Perceived Threats To Food Security And Possible Responses Following An Agro-Terrorist Attack, Lamesha Lashal Craft

Walden Dissertations and Doctoral Studies

The September 11, 2001 terrorist attacks exposed vulnerabilities to U.S. homeland security and defense, leading U.S. officials to analyze threats to domestic and international interests. Terrorist attacks against food and water supplies (agro-terrorism), were deemed a national security threat because of the assessed fear, economic instability, and social instability that could occur following a food shortage. Research indicated a comprehensive response plan does not exist across the federal, state, and local levels of government to mitigate the public's possible responses to a perceived threat to food security and food shortages following an agro-terrorist attack. This ethnographic case study analyzed the …

Could Winter Annual Crop Choice Increase No-Till Double-Crop Soybean Yield In Kentucky?, Ethan M. Swiggart

Theses and Dissertations--Plant and Soil Sciences

Double-cropping soybean (Glycine max L.) after a winter annual crop is common in Kentucky. The preceding winter annual crop may affect double-crop soybean yield in Kentucky. Producers and agronomists have reported greater double-crop soybean yields when preceded by winter canola (Brassica napus L.) rather than winter wheat (Triticum aestivum L.). Explanations for these yield differences remain unresolved. The objectives of this study are to: (1) evaluate double-crop soybean productivity in field environments following four winter annual crop treatments; (2) determine differences of early soybean growth in greenhouse (GH) and cold chamber (CC) environments; and …

Genotype × Environment × Management: Implications For Selection To Heat Stress Tolerance And Nitrogen Use Efficiency In Soft Red Winter Wheat, Kathleen Russell

Theses and Dissertations--Plant and Soil Sciences

The complex interaction of genetics, environment and management in determination of crop yields can interfere with selection progress in breeding programs. Specifically, the impact on selection for nitrogen use efficiency (NUE) in wheat (Triticum aestivum L.) under changing climatic conditions can be confounded by these interactions. Temperature increases for the southeastern United States are projected to range from 1-3°C by 2050 with nighttime temperatures increasing more rapidly than day temperatures. High temperatures are known to affect crop development and breeding for tolerance to heat stress is difficult to achieve in field environments. We utilized a multi-environment trial to assess …