Agronomy and Crop Sciences Commons^™

Arkansas Soybean Performance Tests 2013, R. D. Bond, D. G. Dombek, J. A. Still, R. M. Pryor

Arkansas Agricultural Experiment Station Research Series

Soybean variety and strain performance tests are conducted each year in Arkansas by the University of Arkansas System Division of Agriculture Arkansas Crop Variety Improvement Program. The tests provide information to companies developing varieties and/or marketing seed within the State, and aid the Arkansas Cooperative Extension Service in formulating variety recommendations for soybean producers.

Remote Estimation Of Nitrogen And Chlorophyll Contents In Maize At Leaf And Canopy Levels, Michael Schlemmer, Anatoly A. Gitelson, James S. Schepers, Richard B. Ferguson, Y. Peng, J. Shanahan, Donald Rundquist

Department of Agronomy and Horticulture: Faculty Publications

Leaf and canopy nitrogen (N) status relates strongly to leaf and canopy chlorophyll (Chl) content. Remote sensing is a tool that has the potential to assess N content at leaf, plant, field, regional and global scales. In this study, remote sensing techniques were applied to estimate N and Chl contents of irrigated maize (Zea mays L.) fertilized at five N rates. Leaf N and Chl contents were determined using the red-edge chlorophyll index with R2 of 0.74 and 0.94, respectively. Results showed that at the canopy level, Chl and N contents can be accurately retrieved using green and red-edge Chl …

Optimal Copper Supply Is Required For Normal Plant Iron Deficiency Responses, Brian M. Waters, Laura C. Armbrust

Department of Agronomy and Horticulture: Faculty Publications

Iron (Fe) and copper (Cu) homeostasis are tightly linked across biology. Understanding crosstalk between Fe and Cu nutrition could lead to strategies for improved growth on soils with low or excess metals, with implications for agriculture and phytoremediation. Here, we show that Cu and Fe nutrition interact to increase or decrease Fe and/or Cu accumulation in leaves and Fe uptake processes. Leaf Cu concentration increased under low Fe supply, while high Cu lowered leaf Fe concentration. Ferric reductase activity, an indicator of Fe demand, was inhibited at insufficient or high Cu supply. Surprisingly, plants grown without Fe were more susceptible …

Long-Term Residue And Water Management Effects On Soil Respiration And Soil Aggregate Stability In A Wheat-Soybean, Double-Crop System In Eastern Arkansas, Sharon Faye Smith

Graduate Theses and Dissertations

Sustainability in agriculture is paramount to assuring continued production from our most naturally fertile soils. Storing carbon (C) in soil as organic matter through sustainable agricultural management practices can both remove atmospheric C and improve soil quality. The objective of this study was to evaluate the long-term effects of water management (irrigation and dryland), residue management [burn and no-burn, conventional (CT) and no-tillage (NT)] and residue/fertility level (high and low) on soil respiration and aggregate stability in a wheat- (Triticum aestivum L.) soybean [Glycine max (L.) Merr.], double-crop system in a silt-loam soil (Aquic Fraglossudalf) in the Mississippi River Delta …

Quantitative Trait Loci Associated With Waterlogging Tolerance In A Soft Red Winter Wheat Mapping Population, Diana Carolina Ballesteros Benavides

Graduate Theses and Dissertations

Waterlogging is caused when water stays superficially in the soil for an extended period of time, creating an anaerobic environment which decreases plant growth and grain yield at maturity. Despite the impact of waterlogging on wheat production both globally and in the southeastern U.S., very little is known about the genetic control of waterlogging tolerance in wheat. The objective of this study was to determine the amount of genetic variation for vegetative stage waterlogging tolerance present within a wheat recombinant inbred line (RIL) population and to identify quantitative trait loci (QTL) associated with tolerance and productivity. Experiments were carried out …

Improving The Efficiency Of Fall Applied N With Cover Crops, Corey Lacey

Theses and Dissertations

Nitrate loss studies in Midwestern tile-drained fields have found that fall applied nitrogen (N) resulted in elevated nitrate concentrations in tile water during both the corn and soybean year of a 2 year rotation. The effectiveness of cover crops to reduce nitrate leaching when N is spring applied has been well demonstrated, however there is a dearth of knowledge on the ability of cover crops to reduce nitrate leaching in a system where N is fall applied. Thus, the objectives of this research were to (i) investigate the efficacy of winter cover crops to reduce nitrate leaching from fall applied …

Arkansas Corn And Grain Sorghum Performance Tests 2013, R. D. Bond, D. G. Dombel, J. A. Still, R. M. Pryor

Arkansas Agricultural Experiment Station Research Series

Corn and grain sorghum performance tests are conducted each year in Arkansas by the University of Arkansas System Division of Agriculture. The tests provide information to companies marketing seed within the state, and aid the Arkansas Cooperative Extension Service in formulating recommendations for producers.

Nebraska Variety And Hybrid Tests: Spring Seed Guide - 2014, Teshome Regassa, Dipak Santra, Charles A. Shapiro, Greg Kruger, Bruce Anderson

Department of Agronomy and Horticulture: Faculty Publications

Corn Hybrid Tests Summary...........3–6

Growing Degree Days and Precipitation by County Charts...........7

Corn Tables 2013 A–F.............8–11

Test Location Map.......................... 11

Corn Hybrid Tests........................12–16

Soybean Variety Tests Summary.....................17–18

Soybean Tables 2013 A–F......19–21

Soybean Variety Tests............22–23

Sunflower Variety Tests......24–28

Pea Variety Test......29

Proso Millet Variety Test .... 30

The Effects Of Planting Techniques On Maize Grain Yield And Silage Production, Tyler D. Kaufman

Theses and Dissertations

This thesis is a comprehensive analysis of the effects of seed orientation, row direction and planting population on grain yield, kernel composition, and silage yield and composition. Producers are striving to increase profit by efficiently using their available land area to maximize crop production. However, little research is available testing the effect of seed orientation on grain or silage production. Quantifying the impacts of seed orientation and row direction on grain and silage is essential for maximum crop production. Dissemination of the results should benefit grain and silage producer.

Two experiments were conducted to evaluate the effects of manipulating seed …

Summaries Of Arkansas Cotton Research 2012, Derrick M. Oosterhuis

Arkansas Agricultural Experiment Station Research Series

No abstract provided.

Arkansas Wheat Cultivar Performance Tests 2012-2013, R. E. Mason, R. G. Miller, J. P. Kelley, E. A. Milus

Arkansas Agricultural Experiment Station Research Series

Wheat cultivar performance tests are conducted each year in Arkansas by the Arkansas Agricultural Experiment Station, Department of Crop, Soil and Environmental Sciences. The tests provide information to companies developing cultivars and/or marketing seed within the state and aid the Arkansas Cooperative Extension Service in formulating cultivar recommendations for small-grain producers.

B.R. Wells Rice Research Studies 2012, R. J. Norman, K.A. K. Moldenhauer

Arkansas Agricultural Experiment Station Research Series

No abstract provided.

Selecting Drought Tolerant Soybean Genotypes Using Qtls Associated With Shoot Ureide And Nitrogen Concentrations, Alejandro Bolton

Graduate Theses and Dissertations

In soybean, nitrogen fixation is more sensitive to drought than other physiological processes like photosynthesis. The sensitivity of nitrogen fixation to drought has been associated with high shoot concentrations of ureide and nitrogen under well-watered conditions. Previous research by Hwang et al. (2013) detected quantitative trait loci (QTLs) in a KS4895 by Jackson population associated with shoot ureide and nitrogen concentrations. The present research evaluated the use of these QTLs in selecting genotypes with drought tolerant nitrogen fixation. Our objectives were to compare actual versus expected phenotype of recombinant inbreed lines (RILs) selected using molecular markers, and to evaluate the …

High Yield Soybean Management: Planting Practices, Nutrient Supply, And Growth Modification, Evan Sonderegger

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

Growers are constantly seeking ways to improve yield in soybean [Glycine max (L.) Merr.]. There has been much interest in the use of selected alternative practices to maximize soybean yield. These practices include planting soybean at higher than recommended seeding rates, planting soybean in narrow rows, breaking apical dominance to induce branching, application of strobilurin fungicides prophylactically to minimize disease and extend the seed filling period, the use of N fertilizer both in furrow and foliar applied, and the use of seed treatments to promote early stand establishment and health. Field studies were conducted at the University of Nebraska …

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 …

University Awarded $13.7m Competitive Grant To Support Research On Sorghum And Millet And Decrease Hunger In Africa, Greg Tammen

INTSORMIL Impacts and Bulletins

The U.S. Agency for International Development, or USAID, has announced that Kansas State University is the recipient of a $13.7 million grant from the agency to help end poverty and increase food supplies in semiarid Africa. The award was made under Feed the Future, the U.S. government's global hunger and food security initiative.

The five-year grant establishes the Feed the Future Innovation Lab for Collaborative Research on Sorghum and Millet at Kansas State University. With it, the university will serve as the nation's leading center for international sorghum and millet research, as well as a key component in Feed the …

Automated Conserved Non-Coding Sequence (Cns) Discovery Reveals Differences In Gene Content And Promoter Evolution Among Grasses, Gina Marie Turco, James C. Schnable, Brent S. Pedersen, Michael Freeling

Department of Agronomy and Horticulture: Faculty Publications

Conserved non-coding sequences (CNS) are islands of non-coding sequence that, like protein coding exons, show less divergence in sequence between related species than functionless DNA. Several CNSs have been demonstrated experimentally to function as cis-regulatory regions. However, the specific functions of most CNSs remain unknown. Previous searches for CNS in plants have either anchored on exons and only identified nearby sequences or required years of painstaking manual annotation. Here we present an open source tool that can accurately identify CNSs between any two related species with sequenced genomes, including both those immediately adjacent to exons and distal sequences separated by …

Rate Of Shattercane × Sorghum Hybridization In Situ, Jared J. Schmidt, Jeffrey F. Pedersen, Mark L. Bernards, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

Cultivated sorghum [Sorghum bicolor (L.) Moench subsp. bicolor] can interbreed with a feral weedy relative shattercane [S. bicolor nothosubsp. drummondii (Steud.) de Wet ex Davidse]. Traits introduced from cultivated sorghum could contribute to the invasiveness of a shattercane population. An experiment was conducted to determine the potential for pollenmediated gene flow from grain sorghum to shattercane. Shattercane with juicy midrib (dd) was planted in soybean [Glycine max (L.) Merr.] fields during 2 yr in concentric arcs at varying distances from a 0.39 ha sorghum pollen source with dry midrib (DD). The arcs …

Buckwheat As A Cover Crop In Florida: Mycorrhizal Status, Soil Analysis, And Economic Assessment, Daria Boglaienko

FIU Electronic Theses and Dissertations

This thesis analyses buckwheat as a cover crop in Florida. The study was designed to demonstrate: soil enrichment with nutrients, mycorrhizal arbuscular fungi interactions, growth in different soil types, temperature limitations in Florida, and economic benefits for farmers. Buckwheat was planted at the FIU organic garden (Miami, FL) in early November and harvested in middle December. After incorporation of buckwheat residues, soil analyses indicated the ability of buckwheat to enrich soil with major nutrients, in particular, phosphorus. Symbiosis with arbuscular mycorrhizal fungi increased inorganic phosphorus uptake and plant growth. Regression analysis on aboveground buckwheat biomass weight and soil characteristics showed …

Current State Of Food Security: Research, Education And Outreach In Burkina Universities, Mamoudou H. Dicko Prof.

Pr. Mamoudou H. DICKO, PhD

Burkina Faso is a Sahelian West African country. Current population is about 16 millions and 43.9 % live below the poverty line. Burkina Faso is classified as both a least developed country and a low-income, food-deficit country. The nutritional quality is poor (1830 against 2000 Kcal/person/day). Food insecurity affects 50 % of households, and is increasing in the urban areas. However, Burkina Faso is one of the country that respect the 2003 Maputo’s declaration’s call to invest at least 10 percent of the budget in agriculture, in order to increase agricultural production and attain food self-sufficiency. Several training programs dealing …

Effects Of Leaflet Orientation And Root Morphology On Physiological Traits And Yield In Soybeans., Richard Dewayne Johnson

Doctoral Dissertations

Drought is the most important abiotic stress adversely affecting soybean (Glycine max (L.) Merr.) yield. Leaflet orientation has been shown to reduce leaflet temperatures and transpiration while root morphology has been related to slower wilting phenotypes. The objective of this study was to investigate effects of leaflet orientation and rooting morphology on whole plant transpiration, yield, water use efficiency, and other physiological traits in soybeans using grafting techniques, population lines, near-isogenic lines, and restrained leaf canopy experiments. Experiments were conducted in Knoxville, TN with additional yield trial plots at Springfield, Spring Hill, and Milan, TN. Data were collected on …

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% (LD_{50 …}

Final Evaluation Of The North East Agricultural Region (Near) Strategy, Andrew Blake, Don Burnside, Vicki Williams

All other publications

No abstract provided.

Slow Food: From Farm To Healthy Body, Hannah L. Ruhl

Honors College

Slow Food is a movement devoted to the preservation and promotion of personal, environmental and community health through lifestyle changes which focus on good, clean and fair food. Good refers to food that is healthy and nutritious for the body. Food grown sustainably as in organic agriculture contains higher levels of beneficial compounds such as vitamins, minerals and phytochemicals. Clean food contains no toxic or harmful compounds that can cause detrimental effects on health. Pesticides and other chemicals are often used in food production; as a result they are found in the final product and are often detected in the …

Agricultural Development In The Northern Savannah Of Ghana, Tara N. Wood

Doctor of Plant Health Program: Dissertations and Student Research

Since declaring independence in 1957, the Republic of Ghana has become a stable constitutional democracy. Ghana’s economy has grown substantially over the past decade, yet remains primarily agrarian, accounting for 50% of the total employment and 25% of the country’s Gross Domestic Product. Smallholder rain-fed farming using rudimentary technologies dominates the agricultural sector accounting for 80% of total agricultural production. Approximately 90% of smallholder farms are less than two hectares in size, and produce a diversity of crops. The major crops cultivated in Ghana include numerous cereal, root and tuber, leguminous, fruit, vegetable and industrial crops. Maize is the most …

Influence Of Transplanter Modification And Previous Crop On The Production Of No-Till Dark Tobacco, William Frazier Penick

Masters Theses & Specialist Projects

Dark tobacco (Nicotiana tabacum L.) has historically been produced using
conventional tillage practices. Soil is cultivated multiple times throughout a growing season leading to an increased incidence of soil erosion. No-till systems have been growing in popularity with the advent of new technology that has enabled the practice to be performed effectively and efficiently. With the recent expansion of no-till practices throughout the agricultural community, many crops have had success in producing comparable yields while reducing input costs and saving soil resources. For this experiment, a traditional tobacco transplanter was modified for use in a no-till environment. All modifications were …

Dark Green Color Index As A Method Of Real-Time In-Season Corn Nitrogen Measurement And Fertilization, Upton Siddons

Graduate Theses and Dissertations

Corn (Zea mays L.) requires higher rates of nitrogen fertilizer than any other major U.S. crop partly because N fertilizers are subject to loss through various mechanisms. Because of this, corn may suffer from inadequate nitrogen fertilization or producers may over-apply nitrogen to compensate for early-season nitrogen losses. A timely, accurate, and precise method for measuring in-season corn N status is needed to allow producers to keep nitrogen use efficiency high within a growing season.

Using appropriate software, hue, saturation, and brightness values of digital images can be combined in a dark green color index (DGCI) which is closely associated …

Comparison Of Roundup Ready And Conventional Soybean (Glycine Max L.) Weed Control Systems For Optimizing Yield And Economic Profitability, Brittany Lee Gaban

Masters Theses

Research was conducted in 2010, 2011 and 2012 at the East Tennessee Research and Education Center in Knoxville, TN, in order to compare differences in soybean yield among differing levels of weed control within Roundup Ready® [Glyphosate-resistant] (RR)and conventional soybean cultivars to gain a better understanding of the impact different intensities of weed control have on RR and conventional cropping systems. Results determined that after applying the weed control regimens, there was no significant difference (p

Glyphosate resistant weeds introduce new challenges and create a more costly weed control regimen, especially when using a RR based soybean cultivation operation. Therefore, …

Squash Variety Trials Summer 2012, Rebecca Brown

University of Rhode Island Vegetable Production Research Reports

Variety trials of summer squashes and zucchini conducted in Kingston, RI, USA.

Response Of Nebraska Horseweed (Conyza Canadensis) Populations To Dicamba, Roberto Crespo, Mark L. Bernards, Greg Kruger, Donald Lee, Robert Wilson Jr.

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

Dicamba-resistant soybeans are being developed to provide an additional herbicide mechanism-of-action for postemergence weed control in soybean. Numerous broadleaf species, including horseweed, have evolved resistance to glyphosate. It is anticipated that dicamba will be used by farmers as a primary tool to manage these weeds. Studying and understanding variability in horseweed response to dicamba will aid in developing appropriate risk management strategies to extend the utility of the dicamba-resistance technology. Horseweed plants from ten Nebraska populations were treated with one of nine doses of dicamba in greenhouse experiments. At 28 days after treatment (DAT) visual injury estimations were made and …