Agronomy and Crop Sciences Commons^™

Temperature Effects On Germination Characteristics And Traffic Tolerance Of Newly Established Stands Of Nineteen Commercially Available Cultivars Of Seeded Bermudagrass, Michael Todd Deaton

Theses and Dissertations--Plant and Soil Sciences

Nineteen bermudagrass (Cynodon dactylon (L.) Pers.) cultivars were evaluated for field emergence, establishment rate, traffic tolerance, post-harvest seed coating, germination velocity, and total germination under varying temperature regimes. Two cultivars were evaluated for thermal modeling, day/night temperature fluctuations, day lengths, and effects of fluridone on speed and percentage of total germination.

The effect of cultivar was highly significant for visible field germination, time to 100% cover, and traffic tolerance in both 2010 and 2011. Riviera was the slowest or equivalent to the slowest for visible germination. Casino Royale was the fastest or equivalent to the fastest for visible germination. …

Mortality Impact Of Mon863 Transgenic Maize Roots On Western Corn Rootworm Larvae In The Field, T. L. Clark, D. L. Frank, B. W. French, Lance J. Meinke, D. Moellenbeck, T. T. Vaughn, B. E. Hibbard

Department of Entomology: Faculty Publications

Mortality of western corn rootworm (Diabrotica virgifera virgifera LeConte) due to feeding on MON863 transgenic maize (Zea mays L.) expressing the Cry3Bb1 protein was evaluated at three Missouri sites in both 2003 and 2004 and at one site each in South Dakota, Nebraska, and Iowa in 2004. To do this, survivorship relative to survivorship on isoline maize (i.e., the same genetic background, but without Cry3Bb1) was evaluated. Comparisons were made using low (1650–2500 eggs/m) and high (3300–3500 eggs/m) western corn rootworm egg densities. Significantly fewer beetles were recovered from MON863 than from isoline maize. Emergence from MON863 as …

Using Sex Pheromone Traps In The Decision-Making Process For Pesticide Application Against Fall Armyworm (Spodoptera Frugiperda [Smith] [Lepidoptera: Noctuidae]) Larvae In Maize, Ivan Cruz, Maria De Lourdes Corrêa Figueiredo, Rafael Braga Da Silva, Ivana Fernandes Da Silva, Cristiane De Souza Paula, John E. Foster

Department of Entomology: Faculty Publications

The fall armyworm, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae), is a major pest of maize and frequently demands control measures. The timing of insecticide application is a key factor in determining its efficiency, so an experiment was designed to investigate this. Application of insecticide was based on three criteria: (i) the number of trap-caught moths in a Delta-type trap with a commercial sex pheromone lure placed in the center of the target area, soon after plant emergence; (ii) the percentage of plants exhibiting pinhole-type damage (10% or 20%), and (iii) the percentage of plants exhibiting shot hole–type damage (10% or 20%) …

Cover Crop Mixtures For The Western Corn Belt: Opportunities For Increased Productivity And Stability, Samuel E. Wortman, Charles A. Francis, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

Achieving agronomic and environmental benefits associated with cover crops oft en depends on reliable establishment of a highly productive cover crop community. The objective of this study was to determine if cover crop mixtures can increase productivity and stability compared to single species cover crops, and to identify those components most active in contributing to or detracting from mixture productivity. A rainfed field experiment was conducted near Mead, Nebraska, United States, in 2010 and 2011. Eight individual cover crop species (in either the Brassicaceae [mustard] or Fabaceae [legume] family) and four mixtures of these species (two, four, six, and eight …

Inheritance Of Grain Polyphenol Oxidase (Ppo) Activity In Multiple Wheat (Triticum Aestivum L.) Genetic Backgrounds, Somrudee Nilthong, Robert A. Graybosch, P. Stephen Baenziger

Department of Agronomy and Horticulture: Faculty Publications

Grain polyphenol oxidase (PPO) activity can cause discoloration of wheat (Triticum aestivum L.) food products. Five crosses (PI 117635/Antelope; Fielder/ NW03681; Fielder/Antelope; NW07OR1070/Antelope; NW07OR1066/OR2050272H) were selected to study the genetic inheritance of PPO activity. STS markers, PPO18, PPO29 and STS01, were used to identify lines with putative alleles at the Ppo-A1 and Ppo-D1 loci conditioning low or high PPO activity. ANOVA showed significant genotypic effects on PPO activity (P\0.0001) in all populations. The generations and generation 9 genotype effects were not significant in any population. A putative third (null) genotype at Ppo-A1 (no PCR fragments for PPO18) was discovered …

Identification And Characterization Of Four Missense Mutations In Brown Midrib 12 (Bmr12), The Caffeic O-Methyltranferase (Comt) Of Sorghum, Scott E. Sattler, Nathan A. Palmer, Ana Saballos, Ann M. Greene, Zhanguo Xin, Gautam Sarath, Wilfred Vermerris, Jeffrey F. Pedersen

Department of Agronomy and Horticulture: Faculty Publications

Modifying lignin content and composition are targets to improve bioenergy crops for cellulosic conversion to biofuels. In sorghum and other C4 grasses, the brown midrib mutants have been shown to reduce lignin content and alter its composition. Bmr12 encodes the sorghum caffeic O-methyltransferase, which catalyzes the penultimate step in monolignol biosynthesis. From an EMS-mutagenized TILLING population, four bmr12 mutants were isolated. DNA sequencing identified the four missense mutations in the Bmr12 coding region, which changed evolutionarily conserved amino acids Ala71Val, Pro150Leu, Gly225Asp, and Gly325Ser. The previously characterized bmr12 mutants all contain premature stop codons. These newly identified mutants, along …

Agriculture And Food In Crisis: Conflict, Resistance, And Renewal [Book Review], Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

Edited by Fred Magdoff and Brian Tokar. 2010. Monthly Review Press, New York, New York, United States. 348 p. Paperback, cloth US$ 75.00, paper US$ 18.95, ISBN-13 978-1-58367-226-6.

That doubling of food production over the next four decades will be needed to adequately nourish our human population is not news, but the incredible steps essential to achieve that goal and their political and social implications are less well reported. In this series of 16 essays edited by Fred Magdoff and Brian Tokar, several thoughtful specialists in global food issues explore the historical, biological, economic, energy, political and social dimensions of …

Cultivating A Movement: Excerpts From An Oral History Of Organic Farming And Sustainable Agriculture On California’S Central Coast [Book Review], Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

Edited by I. Reti and S. Rabkin, 2011. University of California, Santa Cruz, Library, Santa Cruz, California, United States. 299 p., US$19.95, ISBN 9-780972-33431, paper.

Often the most compelling evidence for success of organic farming comes from the personal stories of farmers. Coupled with reports on the application of science in organics, the practical knowledge of people in the field provides a rich foundation for the ongoing growth of this intriguing sector of the food system. This collection of interviews by the staff of the Regional History Project is one unique activity of the University of California, Santa Cruz library, …

Estimating Construction Costs For A Low-Cost Quonset-Style Greenhouse, David P. Lambe, Stacy A. Adams, Ellen T. Paparozzi

Department of Agronomy and Horticulture: Faculty Publications

Double polyethylene Quonset-style greenhouses offergrowers and farmers a more cost-effective structure than glass- or acrylic-covered structures for growing plants off-season. These greenhouses are especially applicablefor producing off-season high value crops such as fruits and vegetables for local markets. To support this production alternative, this publication contains a list of greenhouse components, the start-up costs associated with these items and an estimate of the number of person hours required to assemble and outfit a 24-foot-by-72-foot double polyethylene, air-inflated greenhouse structure. As there are many options available for building double polyethylene greenhouses, the main purpose of this publication is to identify the …

The ‘Pi 438489b’ By ‘Hamilton’ Snp-Based Genetic Linkage Map Of Soybean [Glycine Max (L.) Merr.] Identified Quantitative Trait Loci That Underlie Seedling Sds Resistance, Kassem My Abdelmajid, Laura Ramos, Leonor Leandro, Gladys Mbofung, D. L. Hyten, Stella K. Kantartzi, Robert L. Grier Iv, Victor N. Njiti, Khalid Meksem

Department of Agronomy and Horticulture: Faculty Publications

Soybeans [Glycine max (L.) Merr.] are susceptible to many diseases including fungal diseases such as soybean sudden death syndrome (SDS). Several studies reported SDS resistance quantitative trait loci (QTL) on the soybean genome using different recombinant inbred line (RIL) populations and low density genetic linkage maps. High density exclusively single nucleotide polymorphisms-based (SNP-based) maps were not yet reported in soybean. The objectives of this study were (1) to construct a high density SNP-based genetic linkage map of soybean using the ‘PI438489B’ by ‘Hamilton’ (PIxH, n=50) recombinant inbred line population, and (2) to map QTL for SDS resistance using this …

Structural Variants In The Soybean Genome Localize To Clusters Of Biotic Stress-Response Genes, Leah K. Mchale, William J. Haun, Wayne W. Xu, Pudota B. Bhaskar, Justin E. Anderson, D. L. Hyten, Daniel J. Gerhardt, Jeffrey A. Jeddeloh, Robert M. Stupar

Department of Agronomy and Horticulture: Faculty Publications

Genome-wide structural and gene content variations are hypothesized to drive important phenotypic variation within a species. Structural and gene content variations were assessed among four soybean (Glycine max) genotypes using array hybridization and targeted resequencing. Many chromosomes exhibited relatively low rates of structural variation (SV) among genotypes. However, several regions exhibited both copy number and presence-absence variation, the most prominent found on chromosomes 3, 6, 7, 16, and 18. Interestingly, the regions most enriched for SV were specifically localized to gene-rich regions that harbor clustered multigene families. The most abundant classes of gene families associated with these regions …

Identification Of Positive Yield Qtl Alleles From Exotic Soybean Germplasm In Two Backcross Populations, K.-S. Kim, B. W. Diers, D. L. Hyten, M. A. Rouf Mian, J. G. Shannon, R. L. Nelson

Department of Agronomy and Horticulture: Faculty Publications

Increasing seed yield is an important breeding goal of soybean [Glycine max (L.) Merr.] improvement efforts. Due to the small number of ancestors and subsequent breeding and selection, the genetic base of current soybean cultivars in North America is narrow. The objective of this study was to map quantitative trait loci (QTL) in two backcross populations developed using soybean plant introductions as donor parents. The first population included 116 BC₂F₃-derived lines developed using ‘‘Elgin’’ as the recurrent parent and PI 436684 as the donor parent (E population). The second population included 93 BC₃F …

Molecular Mapping Of Soybean Rust Resistance In Soybean Accession Pi 561356 And Snp Haplotype Analysis Of The Rpp1 Region In Diverse Germplasm, Ki-Seung Kim, Jair R. Unfried, D. L. Hyten, Reid D. Frederick, Glen L. Hartman, Randall L. Nelson, Qijian Song, Brian W. Diers

Department of Agronomy and Horticulture: Faculty Publications

Soybean rust (SBR), caused by Phakopsora pachyrhizi Sydow, is one of the most economically important and destructive diseases of soybean [Glycine max (L.) Merr.] and the discovery of novel SBR resistance genes is needed because of virulence diversity in the pathogen. The objectives of this research were to map SBR resistance in plant introduction (PI) 561356 and to identify single nucleotide polymorphism (SNP) haplotypes within the region on soybean chromosome 18 where the SBR resistance gene Rpp1 maps. One-hundred F_2:3 lines derived from a cross between PI 561356 and the susceptible experimental line LD02-4485 were genotyped with genetic …

Advances In Genome Sequencing And Genotyping Technology For Soybean Diversity Analysis, David L. Hyten

Department of Agronomy and Horticulture: Faculty Publications

The completion of a soybean draft whole genome sequence along with advances in sequencing and genotyping technologies are creating a revolution in soybean genomics. The draft whole genome sequence of soybean is allowing researchers to fully take advantage of this new technology and is rapidly changing how soybean germ plasm is mined. Genetic markers such as SNPs can be quickly identified by using next generation sequencing and assayed on a large number of materials using advanced technologies that can genotype tens of thousands of markers on thousands of individuals very rapidly. This ability to qUickly identify and genotype genetic diversity …

High-Resolution Mapping Of Open Chromatin In The Rice Genome, Wenli Zhang, Yufeng Wu, James C. Schnable, Zixian Zeng, Michael Freeling, Gregory E. Crawford, Jiming Jiang

Department of Agronomy and Horticulture: Faculty Publications

Gene expression is controlled by the complex interaction of transcription factors binding to promoters and other regulatory DNA elements. One common characteristic of the genomic regions associated with regulatory proteins is a pronounced sensitivity to DNase I digestion. We generated genome-wide high-resolution maps of DNase I hypersensitive (DH) sites from both seedling and callus tissues of rice (Oryza sativa). Approximately 25% of the DH sites from both tissues were found in putative promoters, indicating that the vast majority of the gene regulatory elements in rice are not located in promoter regions. We found 58% more DH sites in …

Evaluation Of Vascular Changes In Cattle Relative To Time-Off Endophyte-Infected Tall Fescue, Jessica R. Bussard

Theses and Dissertations--Plant and Soil Sciences

Twenty-four steers were grazed on endophyte (Neotyphodium coenophialum)-infected [[Lolium arundinaceum (Schreb.) Darbysh]; E+] tall fescue (TF) and exposed to ergot alkaloids for an 106-d grazing period. Cattle were removed from pasture, placed in dry lots, and fed a non-toxic diet to evaluate changes in vascular contraction relative to time-off E+ TF pasture. Lateral saphenous veins (SV) were biopsied from steers at 0-, 21-, 42-, and 63-d off TF pasture and from 6 control steers at 0- and 63-d off bermudagrass (BG) pasture. To evaluate contractile response, biopsied SV were exposed to increasing concentrations of ergotamine in a multimyograph. Cross-sectional scans …

Steer And Tall Fescue Pasture Responses To Grazing Intensity And Chemical Seedhead Suppression, Ben M. Goff

Theses and Dissertations--Plant and Soil Sciences

Tall fescue (Lolium arundinaceum) is the principal cool-season species within pastures of the southeastern USA and is known to have a mutualistic relationship with a fungal endophyte (Neotyphodium coenophialum) that produces the ergot alkaloids responsible for tall fescue toxicosis. Management of the reproductive growth of tall fescue is necessary, as the seedheads contain the highest concentrations of ergot alkaloids, and livestock have been documented to selectively graze these tissues. Recently, the herbicide Chaparral^™ has been shown to be an effective method to prevent seedhead production in tall fescue pastures while also increasing steer gains at …

Determining The Virulence Of Corn Pathogen Fusarium Verticillioides Utilizing Deletion Mutants Lacking Genes Fv_00027 Or Fv_Nps6, Abigail Zieman

Honors Program Theses

Fusarium verticillioides is an important fungal pathogen of com. Many pathogens have virulent genes which are genes that increase infectivity of the pathogen. After a bioinformatics study, it was determined that genes Fv _ 00027 and Fv _ NPS6 are potential virulent genes in F. verticillioides. To determine if either gene ·contributes to the virulence of the fungus, deletion mutants of F. verticillioides were created lacking either Fv _ 00027 or Fv _ NPS6 genes. These deletion mutants were utilized in an optimized com assay to determine the effect of infectivity on com. To test these deletion mutants, com seeds …

Next Generation Dna Sequencing Technology Delivers Valuable Genetic Markers For The Genomic Orphan Legume Species, Bituminaria Bituminosa, M Pazos-Navarro, Mercedes Dabauza, Enrique Correal, Kelly Hanson, Natasha L. Teakle, Daniel Real, Matthew Nelson

Grain and Other Field Crops Research Articles

Background
Bituminaria bituminosa is a perennial legume species from the Canary Islands and Mediterranean region that has potential as a drought-tolerant pasture species and as a source of pharmaceutical compounds. Three botanical varieties have previously been identified in this species: albomarginata, bituminosa and crassiuscula. B. bituminosa can be considered a genomic 'orphan' species with very few genomic resources available. New DNA sequencing technologies provide an opportunity to develop high quality molecular markers for such orphan species.

Results
432,306 mRNA molecules were sampled from a leaf transcriptome of a single B. bituminosa plant using Roche 454 pyrosequencing, resulting in an …

Expertos Analizan Impacto Del Cambio Climático En Granos Básicos Y Sorgos Forrajeros En El Salvador, Kimberly Christiansen

INTSORMIL Impacts and Bulletins

En el evento participan profesionales de El Salvador, así como de las universidades de Kansas State y Purdue, de Estados Unidos.

Exponer y analizar los principales efectos derivados del cambio climático en los cultivos de El Salvador, así como el impacto que ha tenido la adopción de variedades forrajeras de sorgo en el país, son los objetivos principales de los foros realizados este miércoles por el Centro Nacional de Tecnología Agropecuaria y Forestal “Enrique Álvarez Córdova” (CENTA) con apoyo del Instituto Internacional de Sorgo, Mijo y otros granos (INTSORMIL).

Rentabilidad De La Introduccion De Nuevos Cultivares De Sorgo En La Industria Lactea De El Salvador: Estudio De Impacto Economico, Alexis H. Villacís, John H. Sanders

INTSORMIL Presentations

La introducción de nuevas tecnologías:

Propulsor del desarrollo agrícola.

Sorgos sensitivos:

Reserva o póliza de seguro

Introducidos recientemente desde los años 70 para la siembra en los valles en la segunda temporada.

Últimos 30 años introducción acelerada: Alimentación de aves y en el sector del ganado lechero.

Inversiones de CENTA y MAG.

Aumento de ingresos:

Mayor demanda de alimentos de alta calidad (carne, leche, queso, frutas y verduras).

Investigación agrícola dirigida por René Clara del CENTA: Desarrollo de nuevos cultivares.

Investigación agrícola y extensionismo es costoso:

Rentabilidad de las inversiones públicas?

Quiénes fueron los beneficiarios?

Returns To The Introduction Of New Sorghum Cultivars Into The Dairy Industry Of El Salvador, Alexis H. Villacís, John H. Sanders

INTSORMIL Presentations

The driver of agricultural development is the introduction of new technology. Sensitive sorghums have long been a critical component of hillside Central American agriculture providing a reserve or insurance policy when the principal staple of maize falters. The insensitive sorghums have been more recently introduced since the ‘70s for planting in the valleys in the second season. In the last thirty years the introduction of new insensitive cultivars has accelerated initially for poultry and in the previous two decades for dairy production. This growth has been facilitated by strategic investments in research by CENTA and the Ministry of Agriculture.

As …

Climate Change And Climate Variability: El Salvador – Impacts On Productivity Of Grain Crops And Opportunities For Management And Improvement, P. V. Vara Prasad

INTSORMIL Presentations

1. Climate change and climate variability (past and future).

2. Climate change and variability in El Salvador (climate models).

3. Impact of temperature on grain yield of dry bean, maize and sorghum in El Salvador (crop simulation models).

4. Effects of temperature, drought and/or carbon dioxide: experimental evidence (response of grain sorghum, maize and dry bean).

5. Opportunities for crop management and genetic improvement.

Rentibilidad De La Introducción De Nuevas Variedades De Sorgo Del Centa En La Industria Lechera De El Salvador: Ponencia Presentada En La Conferencia Del Centa: "Cambio Climático E Impacto De Los Sorgos Forrajeros" Diciembre 7, 2011, San Salvador, El Salvador, Alexis H. Villacís, John H. Sanders

INTSORMIL Scientific Publications

El propulsor del desarrollo agrlcola es la introducción de nuevas tecnologlas. Sorgos fotosensitivos' han sido un componente crítico en la agricultura de las laderas centroamericanas, ofreciendo una reserva o póliza de seguro cuando el alimento básico principal de maiz tambalea. Los sorgos foto-insensitivos han sido introducidos recientemente desde los anos 70 para la siembra en postrera en los valles. En los últimos treinta anos, la introducción de nuevas variedades insensitivas se ha acelerado, en un inicio para las aves de corral y en las dos décadas anteriores para la producción lechera. Este crecimiento ha sido posible gracias a las inversiones …

Sorgo Centa S-2 Bmr: Nueva Variedad Forrajera, René Clará Valencia, Salvador Zeledón, Máximo Hernández, Ricardo Estebez Jeorge, Marcos Mejía, Berta Nely Menjivar, Marlon Sorto

INTSORMIL Scientific Publications

El uso tradicional del grano de sorgo en nuestro país ha sido principalmente en la alimentación de especies menores, mientras que los rastrojos de este cultivo se han utilizado para alimentar al ganado bovino especialmente durante la época seca. En ganaderías de subsistencia yen otras explotaciones lecheras más tecnificadas emplean los forrajes conservados como silo o heno para suplir las necesidades alimenticias durante la época seca que es la más crítica para la alimentación.

Algunas ganaderlas tecnificadas prefieren el maíz para ensilarlo debido a su mayor valor nutritivo; sin embargo la incorporación de los genes "bmr' en las nuevas variedades …

Economic Contribution Of The Agricultural Sector To The Arkansas Economy In 2009, Katherine Mcgraw, Jennie Popp, Wayne Miller

AAES Research Reports and Research Bulletins

This report is the sixth in a series of reports examining agriculture’s economic contribution on the Arkansas economy. Utilizing data from the United States Bureau of Economic Analysis (BEA), USDA Economic Research Service (ERS), USDA National Agricultural Statistics Service (NASS), and Minnesota IMPLAN Group, Inc. (MIG), the economic contribution of agriculture on the Arkansas economy was estimated for the most recent year available, 2009. Gross Domestic Product (GDP) by State information for Arkansas in 2009 was compared with those of other states in the southeast U.S. to give a measure of the relative importance of agriculture in Arkansas.2 The total …

Diversification Or Cotton Recovery In The Malian Cotton Zone: Effects On Households And Women, Jeanne Yekeleya Coulibaly

INTSORMIL Scientific Publications

This dissertation investigates income diversification alternatives from the cotton economy and compares those initiatives with present policy measures to restore the cotton sector in Mali. It also derives the welfare implications for women of these various policy measures.

During the decade preceding 2011, farmers’ incomes in the cotton zone of Mali have been significantly affected by the downturn of the cotton economy explained by many factors including the low farm gate cotton price, the declining cotton yields and soil fertility concerns. In 2011, the Malian government substantially increased the farm gate cotton price as a result of the world cotton …

Arkansas Soybean Performance Tests 2011, 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.

The Effects Of Phosphorus Enrichment On Leaf Litter Stoichiometry In A Forested Stream, Bryant Baker

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

The effects of nutrient (N and P) enrichment on leaf litter decomposition in streams have been investigated extensively, but few have explored how P addition alone affects leaf litter stoichiometry (namely the C:P ratio). This study examined how the P content, C:P ratio and decomposition of two types of leaf litter (the recalcitrant Quercus stellata and the more labile Acer saccharum) responded to P enrichment from nutrient diffusing substrata (NDS) which was either unenriched agar or agar enriched with a moderate or high level of P. Leaf litter was sealed in 0.05 mm mesh bags, which excluded invertebrates, housed with …

Rice (Oryza Sativa) Response To Low Glyphosate Rates As Influenced By Cultivar, Growth Stage, And Imazethapyr Applications, Jason R. Meier

Graduate Theses and Dissertations

Off-target movement of glyphosate onto rice is a perennial concern when rice is grown in close proximity to glyphosate-tolernat crops. If differential tolerance to sub-lethal rates of glyphosate exists among rice (Oryza sativa) cultivars, these cultivars could be utilized in breeding programs or glyphosate-drift sensitive areas. Field and greenhouse experiments were conducted in 2006 and 2007 to examine differences among rice cultivars in response to sub-lethal rates of glyphosate, and to examine imidazolinone-tolerant rice response to imazethapyr and sub-lethal rates of glyphosate applied sequentially to determine the potential for either herbicide to predispose rice to greater injury. In the field …