Agronomy and Crop Sciences Commons^™

Arbuscular Mycorrhizal Fungi Differ In Their Ability To Regulate The Expression Of Phosphate Transporters In Maize (Zea Mays L.), Hui Tian, Rhae A. Drijber, Xiaolin Li, Daniel N. Miller, Brian J. Wienhold

Department of Agronomy and Horticulture: Faculty Publications

Previous studies have found that some phosphate (Pi) starvation inducible transporter genes are downregulated and arbuscular mycorrhizal (AM) inducible Pi transporter genes are upregulated in maize roots associated with the fungus Glomus intraradices. However, little is known about the functional diversity of different AM fungal species in influencing the expression of Pi transporters in maize roots. Here, we studied the expression of two Pi transporter genes ZEAma:Pht1;3 (Pi starvation inducible) and ZEAma:Pht1;6 (AM inducible) in maize root colonized by different AM fungal inoculants. Non-mycorrhizal maize, maize colonized by Glomus deserticola (CA113), Glomus intraradices (IA506), Glomus mosseae (CA201), Gigaspora gigantea …

Contents, Discovery Editors

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

No abstract provided.

Discovery: The Student Journal Of Dale Bumpers College Of Agricultural, Food And Life Sciences - Volume 14 2013, Several Authors

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

No abstract provided.

Influence Of Organic Groundcovers On Mycorrhizal Colonization And Symbiosis Of Organically Managed Fruit Crops, Raven Anai Bough, Curt R. Rom

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Ground covers have the potential to impact the crop rhizosphere biology, which includes organisms such as arbuscular mycorrhizal fungi (AMF), which in turn affect the crop host plant through symbiosis. There has been evidence that a ground cover that provides a suitable environment for colonization of AMF and subsequent symbiosis could be a tool in organic fruit production. The objective of this research was to compare colonization of AMF in strawberry plant (Frageria x ananassa cv. Radiance) and apple rootstocks (Malus x domestica, cv. M. 26) grown in a greenhouse affected by various ground cover treatments. Inoculation was achieved by …

The Influence Of Poultry Litter Biochar On Early Season Cotton Growth, Taylor D. Coomer, David E. Longer, Derrick M. Oosterhuis, Dimitra A. Loka

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Cotton is known for being sensitive to cool, wet soils, especially in the early stages of growth. Amendments to soil can aid cotton seedlings in development and nutrient uptake. However, soil amendments can be costly and detrimental to the environment, and alternatives such as the addition of biochar have been considered. Biochar is produced from biomass that has gone through pyrolysis and has been shown to improve plant yield, microbial response, soil structure, soil cation–exchange capacity, and water use efficiency. This study was conducted to evaluate the effect of biochar on early season cotton growth. The aim of this study …

Evaluation Of Cover Crops In High Tunnel Vegetable Rotation, Tyler A. Patrick, Neal Mays, Jason Mcafee, Curt R. Rom

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Organic vegetable production within high tunnels allows for an extended growing season, crop protection, and environmental control. The USDA National Organic Program (NOP) standards mandate evidence that the soil has been maintained and improved over the course of production. Previous studies have indicated the potential of cover crops for reducing competitive vegetation, and improving soil quality, thus resulting in greater plant growth, nutrient uptake, and yield. However, there has been limited work in the confines of high tunnels as part of a tunnel-system rotation. Ten nitrogen-fixing and ten non-legume cover crops were established under a high tunnel and evaluated for …

Characterization Of Seediness Attributes Of Blackberry Genotypes, Bethany Sebesta, John R. Clark, Renee T. Threlfall, Luke R. Howard

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Fresh market blackberries can feel “seedy” when consumed. This “seediness” is associated with the presence of pyrenes which are comprised of a single seed enclosed in an endocarp. Small pyrene size  (<3 mg) is preferred in both fresh-market and processed blackberry products. Yet, the proportion of pyrene weight to total berry weight can be more important than pyrene size. The objective of this study was to determine and compare descriptive sensory analysis and pyrene characteristics of blackberry genotypes from the University of Arkansas System Division of Agriculture blackberry breeding program. Panelists were trained according to Spectrum® methods and evaluated 20 genotypes for overall seediness. Pyrene characteristics, including weight and dimension, were measured for 22 genotypes. Seven of the 22 genotypes had an individual pyrene weight of 3 mg or less. Pyrene weight to berry weight ratio ranged from 2.7% (‘Tupy’) to 5.4% (‘Prime-Ark® 45’). ‘Tupy’ had low individual pyrene weights and a low ratio, which are most likely factors that contribute to its widespread acceptance by consumers. Pyrene weight to berry weight ratio was positively correlated to descriptive overall seediness (r = 0.70) but not to number of pyrenes/berry. Therefore, finding a desirable pyrene weight to berry weight ratio is integral to decreasing perceived seediness in the development of new blackberry cultivars.

Instructions For Authors, Discovery Editors

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

No abstract provided.

Impacts Of Spring-Interseeded Cover Crops On Late-Emerging Weed Suppression And Ground Cover In Corn (Zea Mays L.) Production Systems, Alex D. Bich

Electronic Theses and Dissertations

Any alternative crop management strategy will only be adopted by growers if yield is not negatively impacted, fits within a current management practice, is easily implementable with minimal cost, or provides other beneficial features such as weed control or suppression. Corn production that incorporates a cover crop as an alternative weed control strategy and ground cover may support a sustainable system that is less dependent on herbicidal weed control. In addition, the cover crop may be used as a fall forage, act as a slow release fertilizer source the following year, and provide ground cover to reduce soil erosion. In …

Hybrid, Row Width, And Plant Population Effect On Corn Yield In Kentucky, Chelsea Clay Mcfarland

Theses and Dissertations--Plant and Soil Sciences

Studies were conducted in 2011 and 2012 to determine if narrow row corn (Zea mays L.) and/or greater plant populations could affect yield, time to silking, and other physiological characteristics. Main plots of six hybrids were arranged as a randomized complete bock design with three replications. Split plots were row widths of 76-cm (wide rows) and 20-cm rows on 76-cm spacing (twin rows). Split-split plots were target plant populations of 75 000 and 111 000 plants ha^-1. Corn was no-till seeded into soybean stubble near Lexington, KY in 2011 and 2012. Year interacted with most factors analyzed …

Twin And Narrow Row Width Effects On Corn (Zea Mays L.) Yield And Weed Management, Grant Mackey

Theses and Dissertations--Plant and Soil Sciences

Corn or maize (Zea mays L.) has been grown in North America for many centuries, and an increase in corn production will continue to be needed. Agriculture producers must meet the demands of feeding and providing for an increasing population of people. In order to meet those needs, different production practices are being investigated as a way to increase grain yield.

Field plots were conducted across the state of Kentucky in 2011 and 2012 to evaluate the interaction between hybrid, row width, and plant density on corn yield. The primary objectives were to test if 1) narrower rows increase …

Evaluating The Sustainability Of Four Organic Vegetable Production Systems, Delia W. Scott

Theses and Dissertations--Plant and Soil Sciences

A field study evaluating the sustainability of four organic vegetable production systems was conducted in Lexington, Kentucky in 2006 and 2007. The four systems included no-till, raised beds covered with biodegradable black mulch, bare ground with shallow cultivation, and bare ground with shallow cultivation and wood chip mulch. The two-year study compared yield, weed control, labor, and costs associated with each system, as well as physical, chemical, and microbiological soil characteristics. In 2006, tomatoes (Lycopersicon esculentum Mill.) were grown in the four systems, with no significant difference in yield. Summer squash (Cucurbita pepo L.) was grown in the …

A Land Data Assimilation System (Ldas) Based Dataset For Regional Agro-Climatic Assessments, Xing Liu

Open Access Theses

This study is part of a USDA sponsored project ----Useful to Usable (U2U): "Transforming Climate Variability and Change Information for Cereal Crop Producers". The broader objective includes improving farm resilience and profitability in the U.S. Corn Belt region by transforming existing climate/weather data into usable knowledge and tools for the agricultural community.

The specific tasks of this research are: (1) Build a high-resolution (4 km, daily) agro-climatic dataset using a Land Data Assimilation System (LDAS). (2) Estimate regional corn yield across the Corn Belt with crop models and the agro-climatic dataset. (3) Evaluate the impacts of climate variability due to …

Slurry Seeding Cover Crops, Edwin Alexander Suarez

Open Access Theses

Cover crops improve soil quality through increased organic matter, biological activity, aggregate stability, water infiltration, and nutrient cycling. Slurry seeding, the co-application of cover crop seed and swine (Sus domesticus) manure, is a new practice that saves fuel, time and labor. High salinity and/or ammonia, among other components in swine manure, may reduce cover crop seed germination and limit the use of slurry seeding. Ten cover crop species were evaluated to compare the effects of swine manure components on cover crop seed germination. Seed germination percentages and rates were affected by swine manure but not by equivalent salinity levels established …

Effects Of Selected Pesticides On Calico Scale And Its Natural Enemies, Carlos Roberto Quesada Machigua

Open Access Theses

Calico scale (Eulecanium cerasorum) is an exotic pest of shade and ornamental trees. It feeds on phloem sap, reduces tree vigor and can ultimately kill trees. We observed effects of four foliar applied (bifenthrin, pyriproxyfen, chlorantraniliprole and cyantraniliprole) and two soil applied pesticides (dinotefuran, imidacloprid) on calico scales and their natural enemies on infested thornless honeylocust trees (Gleditsia triacanthos inermis) over three years. Bifenthrin, dinotefuran and cyantraniliprole provided the largest reductions in scale populations when they were applied to egg laying females on branches early in the season. In contrast, bifenthrin and pyriproxyfen provided the most …

Fate Of 17Α-Estradiol, 17Β-Estradiol, And Estrone In Agricultural Soils And Sediments, Michael L. Mashtare Jr

Open Access Dissertations

The shift to concentrated animal production facilities and increasing rural-urban migration has increased the localized land application of nearly 1 billion tons of manure and biosolids annually. Although these applications provide nutrients and contribute to soil tilth, they also serve as a source for an estimated 49 tons of the natural manure-borne estrogens, 17α-estradiol (17α-E2), 17β-estradiol (17β-E2), and estrone (E1). While these estrogens are critical to endocrine systems, the low concentrations observed in the environment can disrupt endocrine function in non-target organisms, e.g., altering secondary sex characteristics which can lead to changes in wildlife communities.

Research presented here focuses on …

Sub1a-Mediated Submergence Tolerance Response In Rice Involves Differential Regulation Of The Brassinosteroid Pathway, Aaron J. Schmitz, Jing J. Folsom, Yusuke Jikamaru, Pamela C. Ronald, Harkamal Walia

Department of Agronomy and Horticulture: Faculty Publications

Submergence 1A (SUB1A), is an ethylene response factor (ERF) that confers submergence tolerance in rice (Oryza sativa) via limiting shoot elongation during the inundation period. SUB1A has been proposed to restrict shoot growth by modulating gibberellic acid (GA) signaling.

Our transcriptome analysis indicated that SUB1A differentially regulates genes associated with brassinosteroid (BR) synthesis during submergence. Consistent with the gene expression data, the SUB1A genotype had higher brassinosteroid levels after submergence compared to the intolerant genotype. Tolerance to submergence can be activated in the intolerant genotype by pretreatment with exogenous brassinolide, which results in restricted shoot elongation …

Herbicide-Resistant Soybeans In Arkansas: Lessons Learned And Future Direction, Amy May West, Raven Bough, Hayley Jernigan, Mike Norton, Katie Beth Thomas, Curt R. Rom, Michael E. Vayda

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

In Arkansas Delta soybean production, glyphosate resistant (GR) Palmer amaranth has significantly impacted weed management. The incidence of herbicide resistant (HR) weeds has far-reaching crop science, economic, and communications implications, which have been explored by the corresponding expertise of our research team members to form a comprehensive literature review. The review was used to develop policy recommendations to address current and future HR genetically modified (GM) crop use and the associated issues. The review of crop science research indicated an overall increase in herbicide application, as well as an increase in weed management programs focused around glyphosate rather than the …

Nutrient Contents, Color, Texture, And Sensory Evaluation Of 12 Arkansas Grown Soybean Cultivars In Canned Products, Quyen Nguyen, Navam Hettiarachchy, Srinivas J. Rayaprolu

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Soybean was introduced in the U.S. in the 1800s, and it has been proven to have several health benefits. New cultivars of soybeans with varying hull colors have been developed using plantbreeding technology. Canning is one of the effective processing methods to extend the shelf life of products. However, very little information is available on canned soybeans. This research studied the composition of 12 soybean cultivars including two cultivars with brown seed coat (R08-4014 and R09-349), three cultivars with black seed coat (R07-1927, R07-10396, and R09-345), and seven regular cultivars with yellow seed coat (R05-1772, R05-4969, R07-2001, R08-4005, R08- 4006, …

Managing Soil Microbial Communities With Organic Amendments To Promote Soil Aggregate Formation And Plant Health, Shawn T. Lucas

Theses and Dissertations--Plant and Soil Sciences

The effects of managing soil with organic amendments were examined with respect to soil microbial community dynamics, macroaggregate formation, and plant physio-genetic responses. The objective was to examine the possibility of managing soil microbial communities via soil management, such that the microbial community would provide agronomic benefits. In part one of this research, effects of three amendments (hairy vetch residue, manure, compost) on soil chemical and microbial properties were examined relative to formation of large macroaggregates in three different soils. Vetch and manure promoted fungal proliferation (measured via two biomarkers: fatty acid methyl ester 18:2ω6c and ergosterol) and also stimulated …