Weed Science Commons^™

Influence Of Six Herbicides Applied To Silage Corn On Fall Planted Rye And Radish Cover Crop Growth In South Dakota Soils, Sydney Pridie

The Journal of Undergraduate Research

Spring preemergence herbicide applications are often used for burndown of existing weeds and residual control, eliminating weed presence during early season crop growth. There has been an increase in the interest in planting cover crops soon after cash crop removal, due to the potential soil and production benefits. However, soil herbicide residuals may result in poor cover crop growth. This study examined the growth of radish (Raphanus sativa) and rye (Secale cereal), species often used as cover crops, in soils that had been treated with residual herbicides about 100 d prior to cover crop planting. The herbicides were applied at ...

Florpyrauxifen-Benzyl Use In Arkansas Rice (Oryza Sativa L.), Hannah Elizabeth Wright

Theses and Dissertations

Florpyrauxifen-benzyl is a synthetic auxin herbicide which was commercially released in 2018 to combat troublesome grass, broadleaf, and sedge weed species in rice. Many factors may influence cultivar response to a new herbicide; hence, it is important to understand factors contributing to crop sensitivity to an herbicide in order to make appropriate recommendations. Prior to the onset of this study, research had been conducted on florpyrauxifen-benzyl in a flooded environment; however, none had been executed in a non-flooded environment. Experiments were conducted to evaluate the response of a long-grain variety ‘CL111’, a medium-grain variety ‘CL272’, and a long-grain hybrid ‘CLXL745 ...

Exploring Putative Herbicide Resistance In Two Summer Annual Grassy Weeds, Benjamin D. Pritchard

Chancellor’s Honors Program Projects

No abstract provided.

Molecular Differentiation Of Astragalus Species And Varieties From The Western United States: The Chloroplast Dna Bridge Between Evolution And Molecular Systematics, Marwa Neyaz, Daniel Cook, Rebecca Creamer

Poisonous Plant Research (PPR)

Locoweeds are the most widespread poisonous plant problem in the world and have been reported in the Western United States since the 1800s, causing tremendous losses in livestock. Consumption of locoweeds by grazing animals stimulates the neurological disease, locoism, characterized by weight loss, ataxia, and lack of muscular coordination. The name locoweed is used for Astragalus and Oxytropis species known to contain swainsonine, the toxic principle produced by the plant endophytic fungus Undifilum. Astragalus includes 2,500-3,000 species and many varieties that have almost identical morphological characteristics that overlap among species, leading to improper identification. Therefore, the aim of ...

Ms Environmental Biology Capstone Project, Alexandra Sorenson

All Regis University Theses

• Chapter 1. Literature Review: Invasive Plant Considerations in Alpine Restoration Project Planning
• Chapter 2. Grant Proposal: Success Rates of Native See Germination on Esplanade-Treated Plots
• Chapter 3. Journal Manuscript: Meta-Analysis of Cheatgrass (Bromus Tectorum) Control with Three Commonly Used Herbicides
• Chapter 4. Stakeholder Analysis: Stakeholder Analysis: Recommendation for Herbicide Use at Lippincott Ranch

An Evaluation Of The Susceptibility Of Goats To Larkspur Toxicosis, Kevin D. Welch, Clint A. Stonecipher, Dale R. Gardner, Benidict T. Green, Daniel Cook

Poisonous Plant Research (PPR)

Larkspurs (Delphinium spp.) are a major cause of cattle losses in western North America, whereas sheep have been shown to be resistant to larkspur toxicosis. Goats are often used as a small ruminant model to study poisonous plants, even though they can be more resistant to some poisonous plants. It is not known how susceptible goats are to the adverse effects of larkspurs. In this study, we evaluated the susceptibility of goats to larkspur toxicosis by performing a dose-response study. We dosed goats with D. barbeyi collected near Cedar City, Utah at 3.3, 4.4, 6.6, 8.8 ...

Evaluation Of The Influence Of Dicamba Exposure On Crop Injury And Canopy Closure Of Glufosinate Resistant Soybean, Zachary K. Perry

Theses and Dissertations--Plant and Soil Sciences

Dicamba-resistant soybean along with lower volatility dicamba formulations have been introduced in an attempt to control herbicide resistant weeds such as Amaranthus palmeri. This introduction has increased the amount of dicamba being applied later in the growing season increasing the prevalence of dicamba off-target movement. Dicamba damage was simulated by applying low rates of dicamba directly on soybeans at rates (0.5 g ae ha^-1, 1 g ae ha^-1 and 5 g ae ha^-1 dicamba) and five-exposure timings from June 1 to July 10. The experimental design was a randomized complete block with four replications at five ...

Glyphosate Plus Dicamba Spray Solution Deposition, Coverage, And Efficacy As Influenced By Spray Nozzle Design And Weed Density, Madison Dru Kramer

Theses and Dissertations--Plant and Soil Sciences

Dicamba injury to sensitive soybean and other broadleaf crops due to drift is a major issue and label restrictions have been created to mitigate dicamba drift. One restriction is the mandated use of low drift nozzles to spray dicamba; these nozzles produce larger droplets and minimize the production of driftable fines. Experiments were conducted to evaluate herbicide coverage, deposition, and efficacy. Three spray nozzle designs and different weed densities were the main factors in the analysis. Dicamba plus glyphosate was applied to 5 to 10 cm tall weeds with a Turbo TeeJet (TT11005) nozzle and two drift reduction nozzles approved ...

Mitigating Herbicide Impacts To Soybean, Grant Lawson Priess

Theses and Dissertations

The rapidity in evolution of herbicide-resistant weeds and the resulting cost to U.S. farmers demonstrate the need to responsibly steward the limited number of herbicides available in agricultural systems. To reduce weed emergence and likewise added selection pressures placed on herbicides, early-season crop canopy formation has been promoted. However, impacts to soybean following a potentially injurious herbicide application have not been thoroughly evaluated. Therefore, field experiments were conducted to determine whether: 1) soybean injury from metribuzin or flumioxazin delayed canopy formation or changed the incidence of pathogen colonization; 2) residual herbicides applied preplant reduced the potential for soybean injury ...

Use Of Harvest Weed Seed Control Strategies In Arkansas Soybean, Jeremy Kyle Green

Theses and Dissertations

Today, most growers use chemical weed management programs; however, a sole reliance on herbicides will place more resistance selection pressure on the weeds to which the herbicide is being applied. As herbicide resistance continues to grow and rob growers of yield, alternative weed control options are being sought to create complex integrated weed management programs to prolong the use of effective herbicides. Harvest weed seed control (HWSC) is a non-chemical practice that has been widely adopted in Australia due to herbicide resistance problems. In most cases, herbicide-resistant weeds that survive applications of herbicides produce viable seed that pass through the ...

The Influence Of Adjacent Weed Populations On Thrips And Iysv In Onion, S. Andrew Swain

All Graduate Theses and Dissertations

Onion thrips (Thrips tabaci) and Iris Yellow Spot Virus (IYSV) constitute a pest complex of global concern for allium growers. Yield losses due to onion thrips alone can be heavy, and in tandem with IYSV, these losses can be complete.

This study was one phase of a multi-phase research project intent on exploring the potential drivers of thrips and virus infestation in onion. Preliminary observations in participating growers’ fields in northern Utah pointed towards a potential link between weedy field borders and thrips/IYSV infestation in onion. Field work was carried out at the Kaysville experiment station examining the possible ...

Investigating Dicamba Tolerance In Grapevine Cultivars Through Drift Simulation Assays, Bryce David Bentley

MSU Graduate Theses

Dicamba is a synthetic auxin herbicide which acts systematically and selectively controls broadleaf plants and has become increasingly popular in the past several years for weed control in commercial agriculture following widespread adoption of dicamba-resistant, transgenic soybean and cotton. Dicamba may be better acknowledged by growers of specialty crops, like grapes, for its capacity to drift miles away from the site of application and deposit on fields, remaining potent enough to cause crop damage and yield loss to vulnerable plants. Grapes are among the most susceptible agronomic crops to dicamba drift, showing visible injury at rates less than 1% of ...

Evaluation Of Topramezone For Use In Rice (Oryza Sativa L.) Production, Matthew Moore

Theses and Dissertations

The rapid development of resistant weeds, particularly to postemergence-applied herbicides, is a growing concern to rice producers worldwide. Barnyardgrass, one of the most problematic weeds in rice cropping systems, alone has been found to be resistant to four herbicide sites of action (SOA) in certain populations, leaving growers no options for control. This unsettling fact has led to research on other SOAs that have not previously been used in US rice. One SOA that has garnered interest is the 4-hydroxyphenylpyruvate dioxygenase (HPPD)- inhibiting herbicides. The only HPPD-inhibitor that will soon be labeled for use in US rice is benzobicyclon. The ...

Evaluation Of Metsulfuron-Methyl For Giant Salvinia (Salvinia Molesta) Control And Non-Target Species Sensitivity, William Prevost

LSU Master's Theses

The invasive aquatic fern giant salvinia (Salvinia molesta D.S. Mitchell) has been invading waterbodies across Louisiana and Texas since 1998. Recently, the non-aquatic herbicide metsulfuron-methyl was found to be highly efficacious against giant salvinia, but limited information is available on application techniques, use rates and concentrations, as well as its impact on non-target species. Therefore, a series of mesocosm experiments were conducted to further evaluate foliar and subsurface applications of metsulfuron against giant salvinia, as well as foliar applications of metsulfuron in combination with aquatic herbicides commonly used for giant salvinia control. When applied to the foliage of giant ...

Varying Weed Densities Alter The Corn Transcriptome, Highlighting A Core Set Of Weed-Induced Genes And Processes With Potential For Manipulating Weed Tolerance, David P. Horvath, Sharon A. Clay, Stephanie A. Bruggeman, James V. Anderson, Wun S. Chao, Kathleen Yeater

Agronomy, Horticulture and Plant Science Faculty Publications

The phenological responses of corn (Zea mays L.) to competition with increasing densities of winter canola (Brassica napus L.) as the weedy competitor were investigated. Changes in the corn transcriptome resulting from varying weed densities were used to identify genes and processes responsive to competition under controlled conditions where light, nutrients, and water were not limited. Increasing densities of weeds resulted in decreased corn growth and development and increased the number and expression intensity of competition-responsive genes. The physiological processes identified in corn that were consistently induced by competition with weeds included protein synthesis and various transport functions. Likewise, numerous ...

Land Rolling Does Not Influence Productivity Of Subsequent-Year Spring Wheat, A. W. Lenssen, U. M. Sainju

Agronomy Publications

Land rolling is a common practice in the northern Great Plains and upper Midwest to push rocks to the soil surface after planting annual grain legumes and forage crops to protect harvest equipment despite the potential to increase weed density and soil erosion and decrease crop yield. Field trials were conducted in 2005 and 2006 to determine if land rolling the previous season influenced weed density or productivity of spring wheat (Triticum aestivum L.) planted following summer fallow or two crops planted the previous season, pea (Pisum sativum L.) and barley (Hordeum vulgare L.). Density of green foxtail [Setaria viridis ...

Herbicide, Douglas D. Archbold, Marta Nosarzewski

Horticulture Faculty Patents

Provided herein are SDH substrates that have use as herbicides in treating pre-emergent and post-emergent weed control. The presently-disclosed subject matter includes an herbicide including SDH substrates such as ribitol and a growth inhibitive effective amount of another adjuvant SDH substrate and/or adjuvant. Methods of treating pre-emergent and post-emergent weeds comprising applying the herbicides disclosed herein in an effective amount to suppress weed growth are also provided.

Insect Population Dynamics, Varietal Preference And Performance Of Organic Bio-Pesticides, Anitha Chitturi, Jeanine Davis, Margaret Bloomquist, Franklin Quarcoo, Kokoasse Kpomblekou-A, Desmond Mortley

Professional Agricultural Workers Journal

Abstract

Organic farming prohibits use of synthetic agrochemicals and encourages use of Integrated Pest Management (IPM) methods. States in the Southeastern US generally lag behind the rest of the country in organic vegetable production partly because of high insect pressures that make it difficult to grow vegetables without pesticides. This study on summer squash (Cucurbita pepo), grown using organic management practices, was conducted at a research station located in Mills River, North Carolina. The objectives of the study were to assess insect population dynamics and to evaluate performance of three OMRI-approved bio-pesticides: Azadirachtin, Pyrethrin and Spinosad against major insect pests ...

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

Research Series

No abstract provided.

Control Of Protoporphyrinogen Oxidase-Resistant Palmer Amaranth, Michael Mckinley Houston

Theses and Dissertations

Already one of the most troublesome weeds in row crop production in the southern U.S., protoporphyrinogen oxidase (PPO)-resistant Palmer amaranth [Amaranthus palmeri (S.) Wats.] was first documented in Arkansas in 2015. Since this confirmation, PPO-resistant Palmer amaranth has been identified throughout the Midsouth. The following research evaluated both current and future herbicide programs for controlling PPO-resistant Palmer amaranth and quantified field-level resistance to PPO-inhibiting herbicides. On-farm research, located in fields with confirmed PPO-resistant Palmer amaranth, was conducted in 2016 and 2017. In preemergence (PRE) herbicide experiments, PPO-inhibiting herbicides still proved useful when combined with herbicides such as metribuzin ...