Digital Commons Network^™

Weed Dynamics During Transition To Conservation Agriculture In Western Kenya Maize Production, Judith A. Odhiambo, Urszula Norton, Dennis Ashilenje, Emmanuel C. Omondi, Jay B. Norton

Agricultural and Environmental Sciences Faculty Research

Weed competition is a significant problem in maize (Zea mays, L.) production in Sub-Saharan Africa. Better understanding of weed management and costs in maize intercropped with beans (Phaseolus vulgaris, L.) during transition to conservation agricultural systems is needed. Changes in weed population and maize growth were assessed for a period of three years at Bungoma where crops are grown twice per year and at Trans-Nzoia where crops are grown once per year. Treatments included three tillage practices: minimum (MT), no-till (NT) and conventional (CT) applied to three cropping systems: continuous maize/bean intercropping (TYPICAL), maize/bean intercropping with relayed mucuna after bean …

Chlorophyll Synthase Under Epigenetic Surveillance Is Critical For Vitamin E Synthesis, And Altered Expression Affects Tocopherol Levels In Arabidopsis, Chunyu Zhang, Wei Zhang, Guodong Ren, Denli Li, Rebecca E. Cahoon, Ming Chen, Yongming Zhou, Bin Yu, Edgar B. Cahoon

Center for Plant Science Innovation: Faculty Publications

Chlorophyll synthase catalyzes the final step in chlorophyll biosynthesis: the esterification of chlorophyllide with either geranylgeranyl diphosphate or phytyl diphosphate (PDP). Recent studies have pointed to the involvement of chlorophyll-linked reduction of geranylgeranyl by geranylgeranyl reductase as a major pathway for the synthesis of the PDP precursor of tocopherols. This indirect pathway of PDP synthesis suggests a key role of chlorophyll synthase in tocopherol production to generate the geranylgeranyl-chlorophyll substrate for geranylgeranyl reductase. In this study, contributions of chlorophyll synthase to tocopherol formation in Arabidopsis (Arabidopsis thaliana) were explored by disrupting and altering expression of the corresponding gene …

The Non-Native Plant Rosa Multifl Ora Expresses Shade Avoidance Traits Under Low Light Availability, Rebecca E. Drenovsky, Daniel M. Dlugos, Hillary Collins, Elise M. Bartelme

Biology

PREMISE OF THE STUDY: Shade tolerance is a key trait promoting invasive plant performance in forest interiors. Rosa multifl ora is a problematic invasive shrub in the northeastern United States, occurring in edge habitats and encroaching into forests. Our objective was to evaluate the shade tolerance of R. multifl ora to assess how ecophysiological traits may facilitate its spread into forest interiors. METHODS: In the fi eld, we documented shrub and seed bank density, fecundity, phenology, and seasonal photosynthetic rates of R. multifl ora in contrasting light environments. In the greenhouse, we exposed seedlings to simulated canopy treatments by altering …

Nebline, August 2015

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

Feature: Nutrition Education Program Reaches 15-Year-Milestone Teaching Nutrition in Lincoln Schools

Food & Health

Family Living

Farm & Acreage

Home & Family Living

Horticulture

Pests & Wildlife

4-H & Youth

Extension Calendar

and other extension news and events

Special pullout section: Lancaster County Super Fair 2015 Schedule & Map

Once Again, My Epiphyllum: Hope, Joy And Excitement, Wenling Ma

Librarian Publications

Wenling Ma describes the second flowering of her Epiphyllum in August 2015.

B. R. Wells Arkansas Rice Research Studies 2014, R. J. Norman, K.A. K. Moldenhauer

Arkansas Agricultural Experiment Station Research Series

No abstract provided.

Nitrogen And Water Effects On Canopy Sensor Measurements For Site-Specific Management Of Crops, Nicholas C. Ward

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Water and nitrogen (N) are undoubtedly the two largest agricultural inputs globally. Coupled with advances in site-specific management technology their integration into production agriculture will allow for the most efficient use these crop input resources. Active canopy sensors offer the ability to measure biophysical plant traits rapidly and make assessments about plant status. Specifically, optical sensor measurements of light reflectance assess plant N status allowing for in-season and on-the-go N recommendations and applications; while infrared thermometers (IRT) measurement of canopy temperature can be used a tool for irrigation management. To evaluate how these technologies work among different plant stress environments …

Growing South Dakota (Summer 2015), College Of Agriculture &. Biological Sciences

Growing South Dakota (Publication of the College of Agriculture, Food and Environmental Sciences)

[Page] 2 Exciting New Era Underway: New Facilities & New Degree Offerings Coming To Fruition
[Page] 5 USDA Report Touts Agriculture Among Best Fields For College Grads
[Page] 6 Critical Need: Essential Services Of ADRDL Need Support For Modernized Facility
[Page] 8 Quarterly Colloquium: State's Ag Leaders Collaborate
[Page] 9 Profiles In Leadership: Developing A Museum To Enrich And Transform Lives
[Page] 10 Productive Partnerships: Collaboration Between Producers & Researchers Guides Research Farm Efforts
[Page] 12 Coordinated Effort: SDSU's John Ball Serves Dual Role To Benefit South Dakota's Trees
[Page] 14 Progressive Perspective: Dan Oedekoven Reflects On Extension's Evolution
[Page] …

Drought And Nitrogen Effects On Maize Canopy Temperature And Stress Indices, David A. Carroll

Theses and Dissertations

Increased water scarcity due to changing climate, population growth, and economic development is a major threat to the sustainability of irrigated agriculture in the Western United States and other regions around the world. Management practices, such as controlled deficit irrigation, that seek to maximize the productivity of a limited water supply are critical. When using controlled deficit irrigation, remote sensing of crop canopy temperature is a useful tool for assessing crop water status and for more precise irrigation management. However, there is potential that nutrient deficiencies could compound the interpretation of water status from leaf temperature by altering leaf color …

Functional Analysis Of The Mms19 Gene In Carica Papaya, Jorge A. Trujillo

Theses and Dissertations - UTB/UTPA

All organisms face DNA-damaging radiation in the form of UV light and must have mechanisms to repair or undo damage. Plants being stationary organisms must cope with damaging UV rays in a molecular fashion and so have developed many forms of resistance. MMS19 is implicated in DNA repair indirectly as a nuclear encoded gene that binds onto protein assembly complexes in the cytosol. A mutant within the SunUp variety of Carica papaya has a large deletion for MMS19 and presents a diminutive phenotype. Deficient DNA repair mechanisms will shunt cells out of the natural cell cycle and reduce cell proliferation …

When It Comes To Clethra: Roots Matter, W. John Hayden

Biology Faculty Publications

Roots, too often, are out of sight and out of mind, but they are critical for vigorous, healthy plant growth. All plant enthusiasts—including gardeners, farmers, foresters, and naturalists—should think about and appreciate roots if they wish to acquire a holistic understanding of plant biology. This article introduces readers to the mycorrhizal roots of the 2015 VNPS Wildflower of the Year, Clethra alnifolia (Sweet Pepperbush), and explores the diversity of mycorrhizae in a closely related family, Ericaceae.

Nebline, July 2015

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

Feature: Reduce Bullying and Cyberbullying Through Social and Emotional Learning

Food & Health

Family Living

Farm & Acreage

Horticulture

Pests & Wildlife

4-H & Youth

Extension Calendar

and other extension news and events

Biochemical And Proteomic Profiling Of Maize Endosperm Texture And Protein Quality, Kyla J. Morton

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

The research described herein, focuses on the biochemical and proteomic analysis of the maize endosperm and what influences kernel texture. Quality Protein Maize (QPM) is a hard endosperm version of the high-lysine opaque2 (o2) mutant but the genes involved in modifying the soft o2 endosperm are unknown. Pyrophosphate (PPi)-dependent fructose 6-phosphate 1-phosphotransferase (PFP) catalyzes the ATP-independent conversion of fructose 6-phosphate to fructose 1, 6-bisphosphate in glycolysis. We found a large increase in transcript and protein levels of the alpha regulatory subunit of PFP (PFPα) in QPM endosperm. In vitro enzyme assays show a significant increase in forward PFP …

Effect Of Nitrogen Fertilizer Rates And Two-Spotted Spider Mite Incidence On 'Strawberry Festival' Strawberry Cultivar Performance, Megan E. Mcgovern

Graduate Theses and Dissertations

The decline in strawberry (Fragaria x ananassa Duch.) production in Arkansas over the last 50 years has sparked an interest in the use of season extension techniques to improve yield and fruit quality. High tunnel strawberry production has the potential to become a profitable and sustainable production system; however, information on nutrient and pest management is limited.

The overall objective of this study was to determine the response of ‘St. Festival’ strawberry cultivar to different nitrogen fertilizer rates in order to develop a fertilization program for strawberries grown under high tunnel production systems. Experiments were conducted at the University of …

Evaluation Of Control Strategies For The Spread Of Citrus Greening, Vicente Valle Martinez

Theses and Dissertations - UTB/UTPA

Huanglongbing, also known as citrus greening, is a vector-based disease in citrus (with no cure known to date) that has drastically affected the citrus production in Florida in less than a decade and has been recently detected in Texas and California. In this paper, an epidemic model of the spatial spread of the disease is implemented among commercial and residential groves by taking into consideration the diffusion patterns of the psyllid vectors. A system of differential equations resembling one for malaria infection in humans is derived to evaluate different control methods such as quarantine, treatment, removal, foliar treatment, and pest …

Association Mapping For Elemental Concentration Resulting From Vegetative Stage Soil Waterlogging Stress In Wheat (Triticum Aestivum L.), Maria Nelly Arguello-Blanco

Graduate Theses and Dissertations

Soil waterlogging (WL) affects wheat production worldwide, including the southern of the U.S. Little is known about the genetics of tolerance mechanisms to WL, particularly of potentially toxic elements such as aluminum, iron and sodium. The objectives of this study were to use association mapping (AM) to identify SNP associated with the EC in the vegetative tissue of a set of 240 diverse soft winter wheat genotypes (AM panel) grown under field WL and to determine the impact of WL on wheat yield (GY) and yield components in a set 28 adapted cultivars (YT)

YT study showed reductions in GY …

Temperature In The Cotton (Gossypium Hirsutum L.) Canopy And Effects On Cotton Leaf And Boll Growth, Maria Soledad Berlangieri Costa

Graduate Theses and Dissertations

Cotton development and yield are negatively influenced by extremes temperatures, mainly during reproductive stage. Ambient air temperature is used to evaluate temperature stress effect on yield under field conditions; however, there is evidence that actual temperatures in the canopy where bolls develop are different. In terms of cotton responses, there is limited research about the effects of elevated day and night temperatures upon boll carbohydrate content, size, and boll respiration. Field and growth chamber experiments were performed during 2014-2015 using the cotton (Gossypium hirsutum L.) cultivar DP0912B2RF. Field studies for determining temperature gradients through the canopy consisted of two planting …

Grower Adoption Of An Integrated Pest Management Package For Management Of Mango-Infesting Fruit Flies (Diptera: Tephritidae) In Embu, Kenya, J. K. Korir, H. D. Affognon, C. N. Ritho, W. S. Kingori, P. Irungu, S. A. Mohamed, S. Ekesi

All Peer-Reviewed Publications

Mango (Mangifera indica L.) is a well-recognized fruit of economic and nutritional importance to smallholder farmers across Africa. Production and marketing of this fruit is, however, severely hampered by fruit fly infestation that is responsible for enormous fruit losses. In Kenya, control of this pest is primarily dependent on the use of chemical pesticides, a strategy that has been shown to be ineffective. Although the recently introduced fruit fly integrated pest management (IPM) package developed by the International Centre of Insect Physiology and Ecology (icipe) has proved to be effective against this pest, there is little demonstrable investigation on its …

Traversing Swanton Road, 20th Ed., James A. West

Academic, Government & Associated Organizational Research Resources

Situated at the northwest end of Santa Cruz County and occupying circa 30 square miles of sharply contrasted terrain, the Scott Creek Watershed concentrates within its geomorphological boundaries, at least 10-12% of California's flora, both native and introduced. Paradoxically, the use/abuse that the watershed has sustained over the past 140+ years, has not necessarily diminished the biodiversity and perhaps parallels the naturally disruptive but biologically energizing processes (fire, flooding, landslides and erosion), which have also been historically documented for the area for +60 years. This is an early edition of an extensive document by James A. West. Please visit the …

Prokaryotic Diversity In The Rhizosphere Of Organic, Intensive, And Transitional Coffee Farms In Brazil, Adam Caldwell, Livia Silva, Cynthia Da Silva, Cleber Ouverney

Faculty Publications, Biological Sciences

Despite a continuous rise in consumption of coffee over the past 60 years and recent studies showing positive benefits linked to human health, intensive coffee farming practices have been associated with environmental damage, risks to human health, and reductions in biodiversity. In contrast, organic farming has become an increasingly popular alternative, with both environmental and health benefits. This study aimed to characterize and determine the differences in the prokaryotic soil microbiology of three Brazilian coffee farms: one practicing intensive farming, one practicing organic farming, and one undergoing a transition from intensive to organic practices. Soil samples were collected from 20 …

Combinatorial Effects Of Fatty Acid Elongase Enzymes On Nervonic Acid Production In Camelina Sativa, Dongxin Huai, Yuanyuan Zhang, Chunyu Zhang, Edgar B. Cahoon, Yongming Zhou

Center for Plant Science Innovation: Faculty Publications

Very long chain fatty acids (VLCFAs) with chain lengths of 20 carbons and longer provide feedstocks for various applications; therefore, improvement of VLCFA contents in seeds has become an important goal for oilseed enhancement. VLCFA biosynthesis is controlled by a multi-enzyme protein complex referred to as fatty acid elongase, which is composed of β-ketoacyl-CoA synthase (KCS), β-ketoacyl-CoA reductase (KCR), β-hydroxyacyl-CoA dehydratase (HCD) and enoyl reductase (ECR). KCS has been identified as the ratelimiting enzyme, but little is known about the involvement of other three enzymes in VLCFA production. Here, the combinatorial effects of fatty acid elongase enzymes on VLCFA production …

Nebline, June 2015

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

Feature: After-Harvest Care Of Asparagus

Food & Health

Family Living

Farm & Acreage

Horticulture

Pests & Wildlife

4-H & Youth

Extension Calendar

and other extension news and events

The Amaranth (Amaranthus Hypochondriacus) Genome: Genome, Transcriptome And Physical Map Assembly, Jared William Clouse

Student Works

Amaranthus hypochondriacus is an emerging pseudo-cereal native to the New World which has garnered increased attention in recent years due to its nutritional quality, in particular its seed protein, and more specifically its high levels of the essential amino acid lysine. It belongs to the Amaranthaceae family, is an ancient paleotetraploid that shows amphidiploid inheritance (2n=32), and has an estimated genome size of 466 Mb. Here we present a high-quality draft genome sequence of the grain amaranth A. hypochondriacus. The genome assembly consisted of 377 Mb in 3,518 scaffolds with an N50 of 371 kb. Repetitive element analysis predicted that …

Genetic Engineering Online Lessons Improve Teaching And Increase Knowledge And Accepting Attitudes Among Students, Grace Troupe

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Genetic engineering has been used in the production of food in the U.S. for nearly three decades, however, science literacy in genetic engineering among consumers is still low. To address this problem, an online resource called The Journey of a Gene (passel.unl.edu/ge) was created to help incorporate genetic engineering education in high school and college curriculums. Here we report two studies conducted to evaluate the effectiveness of The Journey of a Gene in 1) improving student knowledge and attitudes about genetic engineering and 2) helping teachers increase their knowledge as well as quantity and quality of genetic engineering instruction. In …

The Amaranth (Amaranthus Hypochondriacus) Genome: Genome, Transcriptome And Physical Map Assembly, Jared William Clouse

Theses and Dissertations

Amaranthus hypochondriacus is an emerging pseudo-cereal native to the New World which has garnered increased attention in recent years due to its nutritional quality, in particular its seed protein, and more specifically its high levels of the essential amino acid lysine. It belongs to the Amaranthaceae family, is an ancient paleotetraploid that shows amphidiploid inheritance (2n=32), and has an estimated genome size of 466 Mb. Here we present a high-quality draft genome sequence of the grain amaranth A. hypochondriacus. The genome assembly consisted of 377 Mb in 3,518 scaffolds with an N50 of 371 kb. Repetitive element analysis predicted that …

The Biological Consequences Of Kaolin Geophagia, Deloris Alexander, Desire Richardson, Lakisha Odom, Kara Cromwell, Dejuana Grant, Micoya Myers, Eddy Cadet, Hamid Mahama, Vijaya Rangari, Ralphenia Pace, Ramble Ankumah, Kokoasse Kpomblekou-A, Curtis Fluker

Professional Agricultural Workers Journal

Abstract

Kaolin geophagia is associated with the relief of gastrointestinal distress, but it may also cause adverse health effects on the body. This study was designed to: assess kaolin composition; test if 129SvEv mice would consume kaolin and determine the consequences of consumption; and assess rotational stress modulation of consumption. Thirteen kaolin samples were purchased from Alabama and Georgia stores. Chemical and physical properties were characterized for each sample using a Munsell chart, pH meter, Energy Dispersive Spectroscopy, Transmission Electron Microscopy, Visible Near-InfraRed Spectra, and Inductively Coupled Plasma-Optical Emission Spectrometry. Kaolin was then given to mice as food supplements and …

Predictive Modeling Of Oxygen Transmission Through Micro-Perforations For Packaging Applications, Ayman Abdellatief, Bruce A. Welt, Jason Butler, Eric Mclamore, Arthur Teixeira, Sanjay Shukla

Journal of Applied Packaging Research

Methods for creating precise perforations in respiring produce packaging are being increasingly adopted. Knowledge of oxygen transfer through perforated packaging and oxygen distribution in packages is necessary for successful packaging design of fresh produce. An approach to modeling perforated packaging performance was developed using a cylindrical chamber with precision perforations using Fick’s second law. The model was simulated using two techniques including Finite Element Method (FEM) using commercially available software and Finite Volume Method (FVM) through programming. Perforations were approximated as a source term in the second method. Both simulation techniques showed trends similar to experimental data.

Silencing Of The Oshp Gene For Increasing Abiotic Stress Tolerance In Rice, Virginia Ann Boyett

Theses and Dissertations

This thesis project involves increasing the tolerance to abiotic stresses in rice through silencing the OsHP gene, a homolog of Arabidopsis AtClb, which has been identified as a negative regulator of response to abiotic stresses. A fragment of the OsHP gene was cloned into a Gateway entry vector pENTR/D-TOPO, and a silencing construct was created with the Gateway destination vector pANDA through an LR clonase reaction. Embryogenic callus tissue was generated from seed of the rice cultivars `Nipponbare' and `LaGrue'. Biolistic and Agrobacterium-mediated transformation procedures were used to transfer the pANDA_OsHP silencing construct into the rice callus tissue. Transformed calli …

Fishing For A Sustainable Future: Aquaponics As A Method Of Food Production, Richard Ramsundar

Student Theses 2015-Present

This thesis compares and explains the advantages aquaponics farming has over modern industrial intensive farming. Through a comparison natural capital usage, conservation, recycling and cost, the thesis advocates for the expansion of aquaponics usage in urban settings. The thesis also explains the history of intensive farming and aquaponics in America, the science of how aquaponics operates, the economic and environmental costs of modern intensive farming versus aquaponics farming, and the social implications of aquaponics. Lastly, I propose a policy that reallocates farm subsidies by modifying the Farm Bill. Then I propose policies that support creating a new standard of farm …

Water Balance Of Flooded Rice In The Tropics, Siva Sivapalan

Books & book chapters

Department of Agriculture and Food, WA staff member authored "Water Balance of Flooded Rice in the Tropics" in the publication Irrigation and Drainage - Sustainable Strategies and Systems’, edited by Muhammad Salik Javaid, published by INTECH, May 2015

Chapter Summary: Excess groundwater recharge rates under irrigated agriculture may lead to problems such as rising watertable, waterlogging and salinity. In irrigated areas, growers may need to manage this water and hence, understanding what leakage is attributed to what crops will become more important. In this study, evaporation, transpiration, and deep percolation losses were estimated for ponded rice culture, using a …