Agronomy and Crop Sciences Commons^™

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

Graduate 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 …

Mitigating Herbicide Impacts To Soybean, Grant Lawson Priess

Graduate 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 and …

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

Graduate 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 …

Grains, Seeds And Hay Industry Funding Scheme Annual Report 2018/2019, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity published reports

The Grains, Seeds and Hay Industry Funding Scheme (IFS) has been operating since 2010 to address biosecurity threats relevant to Western Australia’s (WA) grains, seeds and hay industry. The Scheme was established under the Biosecurity and Agriculture Management Act 2007 to enable growers to identify the pest and disease priorities at a whole-of-industry level and raise funds for activities to address these priorities.

There are currently three Industry Funding Schemes in operation. In addition to the Grains, Seeds and Hay IFS, there is a Cattle IFS and a Sheep and Goat IFS. The three IFSs operate in a similar manner. …

B.R. Wells Arkansas Rice Research Studies 2018, R. J. Norman, K. A.K. Moldenhauer

Arkansas Agricultural Experiment Station Research Series

No abstract provided.

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

Graduate 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 and/or pyroxasulfone. …

Herbicide Drift Influence On Amaranthus Spp. Herbicide Resistance Evolution, Bruno Canella Vieira

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

The adverse consequences of herbicide drift towards sensitive crops have been extensively reported in the literature. However, no information is available on the consequences of herbicide drift onto weed species inhabiting boundaries of agricultural fields. Exposure to herbicide drift could be detrimental to long-term weed management as several weed species have evolved herbicide resistance after recurrent selection with low herbicide rates. Despite the herbicide drift exposure and its potential implications on resistance evolution and weed management, resistance prone weed species such as Palmer amaranth (Amaranthus palmeri) and waterhemp (Amaranthus tuberculatus) are often neglected and not properly …

Bedstraw Eradication Program: Annual Report To Grain Growers 2018/2019, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity published reports

The Grains, Seeds and Hay Industry Management Committee (GSHIMC) believes the current program is delivering the best value for the funding provided and is achieving the project outcomes of containment and eradication.

Approved programs are developed annually for each infested property in consultation with GSHIMC, the Department of Primary Industries and Regional Development (DPIRD) and the landholders detailing management actions, estimated costs and timeframes of the agreed actions.

The two infested properties have now entered the final Release Phase of a nine-year eradication program. The program is implemented by DPIRD and includes six consecutive years of winter spray treatments, followed …

Using Drones For Precision Agriculture, Jiyul Chang, Madhav P. Nepal

Madhav Nepal

In this teaching module, students will learn what Precision Agriculture is and how to apply drone into Precision Agriculture practices. To use data (images) taken by drone, students will learn the basic theory of Remote Sensing. Using images, students learn how to make NDVI (Normalized Difference Vegetation Index) maps and how to apply drone (remote sensing technique) in agriculture.

Evaluation Of Crop Tolerance And Weed Control In Corn And Grain Sorghum With Atrazine Replacements, Jacob Thomas Richburg

Graduate Theses and Dissertations

Atrazine is a foundational herbicide for weed control in both corn (Zea mays L.) and grain sorghum [Sorghum bicolor (L.) Moench] production. However, studies have shown that while atrazine may be an effective herbicide for preemergence and postemergence control of weeds, it also has risks. The low Koc of atrazine as well as its extensive use over the past 50 years have led it to become the most common groundwater contaminant near agricultural soils. Given these findings, atrazine has faced severe scrutiny while under consideration for reregistration. In the event that atrazine is not reregistered, corn and grain sorghum producers …

Science Communication In Agriculture: The Role Of The Trusted Adviser, Lee Galen Briese

Doctor of Plant Health Program: Dissertations and Student Research

Agronomy is not simply the selling of agricultural products to farmers, nor is it the process of solving singular production problems. Agronomy is defined as the integrated, holistic perspective of agriculture (ASA, 2019) and “agronomists are specialists in crop and soil sciences, as well as ecology” (ASA, 2019). While scientific investigation and discovery are essential to understanding systems function, the tangible benefits from our knowledge stems from the application to solve problems. Clear communication is vital to successfully help stakeholders understand the importance of the science and help scientists understand the challenges stakeholders face. However, to successfully put science into …

Integrated Management Of Phytophthora Stem And Root Rot Of Soybean And The Effect Of Soil-Applied Herbicides On Seedling Disease Incidence, Vinicius Castelli Garnica

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

Soybean seedling diseases and Phytophthora stem and root rot (PSRR; caused by Phytophthora sojae) are two of the most economically important diseases in North Central U.S. Remarkable differences in disease incidence occur each year, which demonstrate that abiotic and biotic factors must interact for disease onset and development. During 2017 and 2018, field studies were conducted to (i) address the efficacy of seed treatment and genetic resistance for PSRR management on soybean population, canopy coverage (CC), and yield, and (ii) investigate potential interactions between pre-emergence (PRE) herbicides and the incidence of seedling diseases in alluvial soils in Nebraska.

Despite …

Effect Of Soil-Applied Protoporphyrinogen Oxidase Inhibitor Herbicides On Soybean Seedling Disease, Nicholas J. Arneson

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

Seedling disease is one the most economically important diseases of soybean in the United States. It is commonly caused by Fusarium spp., Rhizoctonia solani, Pythium spp., and Phytophthora sojae, alone, or together as a disease complex. Fungicide seed treatments continue to provide the most consistent management of seedling diseases. Soil-applied protoporphyrinogen oxidase (PPO) inhibitor herbicides are used preemergence in soybean production to manage several broadleaf weeds. Applications of PPO-inhibitors can result in phytotoxic injury to soybean when environmental conditions are not favorable for soybean growth. These environmental conditions can favor seedling disease development as well. In this thesis, two …

Assessment Of Control Of Ppo-Resistant Palmer Amaranth And Salvage Options In Herbicide-Resistant Cotton, Wyatt D. Coffman

Graduate Theses and Dissertations

Palmer amaranth has been the most limiting weed in cotton production in the state of Arkansas for many years. Recently, resistance of Palmer amaranth to the protoporphyrinogen oxidase (PPO)-inhibiting site of action has been discovered at various locations across the cotton-producing region of the state. Cotton varieties have been developed with resistance to synthetic auxin (WSSA Group 4) herbicides. However, research to date has shown PPO-resistant Palmer amaranth to be more difficult to control with herbicides that target alternative sites of action. Herbicide efficacy is also known to vary with weed size, varying spray parameters, and environmental conditions. Preliminary research …

Mulch Treatment Effect On Weed Biomass And Yields Of Organic Sweetpotato Cultivars, Sochinwechi I Nwosisi, Dilip Nandwani, Dafeng Hui

Biology Faculty Research

Weeds are a challenge, particularly in organic agriculture, due to restrictions on the application of synthetic herbicides and chemicals. A preliminary cultivar evaluation trial of organic sweetpotato was conducted in 2015 at Tennessee State University certified organic farm. Three mulches: wheat straw, pine needle, and black plastic mulch, along with a control (no mulch), were evaluated for their weed management abilities in a sweetpotato field. Four cultivars of sweetpotato were planted in 0.91 m wide mulch beds with 0.3 m row spacing anddrip irrigated with four replications. Data was collected during the growing season on the dry weight of weeds …

Strategies To Overcome Antagonism Of Quizalofop-P-Ethyl When Applied In Mixture With Other Herbicides, Lucas C. Webster

LSU Master's Theses

A field study was conducted in 2017 and 2018 at the LSU Agricultural Center H. Rouse Caffey Rice Research Station (RRS) near Crowley, LA. to evaluate the influence of different adjuvants in overcoming the antagonism of quizalofop when mixed with bispyribac in Louisiana rice production. The antagonism of quizalofop mixed with bispyribac plus HCOC at 14 DAIT was overcome with a neutral interaction observed at 28 DAIT for barnyardgrass control with an observed control of 91%, compared with an expected control of 97%. The addition of COC, SNS or HCOC into a mixture of quizalofop plus bispyribac provided synergistic or …

Using Drones For Precision Agriculture, Jiyul Chang, Madhav P. Nepal

iLEARN Teaching Resources

In this teaching module, students will learn what Precision Agriculture is and how to apply drone into Precision Agriculture practices. To use data (images) taken by drone, students will learn the basic theory of Remote Sensing. Using images, students learn how to make NDVI (Normalized Difference Vegetation Index) maps and how to apply drone (remote sensing technique) in agriculture.

Effects Of Spring-Planted Cover Crops On Weed Suppression And Winter Wheat Grain Yield In Western Kansas, A. K. Obour, J. D. Holman, J. A. Dille, V. Kumar

Kansas Agricultural Experiment Station Research Reports

Herbicide resistant (HR) weeds pose a major challenge to continuous no-tillage (NT) dryland crop management systems. Integrating cover crop (CCs) in dryland crop rota­tions could suppress weeds and provide a weed management option for HR weeds in NT systems. Field experiments were conducted to investigate weed suppression poten­tial of spring-planted CCs and their impacts on subsequent winter wheat grain yields. The CCs were oat/triticale, oat/triticale/pea, spring pea, and chem-fallow (standard) over 3 years and 2 locations in western Kansas. A weedy-fallow check was added to compare weed suppression of CCs in 2 out of the 3 years. Results showed CC …

Herbicide Strategies For Managing Glyphosate- And Dicamba-Resistant Kochia In Roundup Ready 2 Xtend Soybean, V. Kumar, R. Liu, T. Lambert, P. W. Stahlman

Kansas Agricultural Experiment Station Research Reports

Kochia populations with multiple resistance to glyphosate and dicamba are an increasing concern for growers in the High Plains region, including Kansas. A field study was conducted at the Kansas State University Agricultural Research Center near Hays, KS, to evaluate and develop herbicide options for controlling glyphosate- and dicamba-resistant kochia in Roundup Ready 2 Xtend soybean. The study site was uniformly infested with a glyphosate- and dicamba-resistant kochia population prior to soybean planting. Fifteen herbicide treatments (programs), including PRE alone and PRE followed by (fb) POST-applied herbicides, were investigated in a randomized complete block design with four replications. …

Characterization And Management Of Glyphosate- And Hppd-Inhibitor-Resistant Palmer Amaranth In Kansas Corn Production, V. Kumar, R. Liu, T. Lambert

Kansas Agricultural Experiment Station Research Reports

Multiple herbicide-resistant (MHR) Palmer amaranth is an increasing management concern for Kansas grain producers. The main purpose of this research was to 1) char­acterize the resistance levels to glyphosate (Roundup PowerMax) and mesotrione (Callisto) in an MHR Palmer amaranth population collected from Stafford County, KS, compared to a known herbicide-susceptible (SUS) population; and 2) to evaluate the effectiveness of preemergence (PRE), PRE followed by (fb) early post emergence (EPOST), and PREfblate POST (LPOST) herbicide programs for controlling this MHR population in Roundup Ready and LibertyLink corn. To achieve these objec­tives, a whole plant dose-response study was …

Influence Of Cultural Practices And Herbicide Programs For Managing Glyphosate-Resistant Palmer Amaranth In Cold-Tolerant Sorghum, R. Liu, V. Kumar, R. Perumal, T. Lambert, T. Ostmeyer

Kansas Agricultural Experiment Station Research Reports

The widespread evolution of glyphosate-resistant (GR) Palmer amaranth (Amaran­thus palmeriS. Wats) has become a serious management concern for grain sorghum producers in western Kansas. To develop an integrated weed management (IWM) system, a field study was conducted at the Kansas State University Agricultural Research Center (KSU-ARC) in Hays, KS, in 2018, to evaluate the effect of sorghum hybrid, row spacing, and herbicide programs on GR Palmer amaranth control, shoot dry weight reduction, and sorghum grain yield. Treatments included two cold-tolerant grain sorghum hybrids: Pioneer 87P06 (commercial check) and ATx645/ ARCH12012R (developed by the KSU-ARC breeding program); row spacing …

Effective Herbicide Options For Controlling Glyphosate-Resistant Palmer Amaranth In Roundup Ready 2 Xtend Soybean, V. Kumar, R. Liu, T. Lambert, D. E. Peterson, C. L. Minihan, P. W. Stahlman

Kansas Agricultural Experiment Station Research Reports

Glyphosate-resistant (GR) Palmer amaranth has become a serious challenge for soybean producers in the mid-south and central United States, including Kansas. Field experi­ments were conducted at the Kansas State University Agricultural Research Center (KSU-ARC) near Hays, KS, and Kansas State University Ashland Bottoms (KSU-AB) research farm near Manhattan, KS, to determine the effectiveness of preemergence (PRE) and PRE followed by (fb) postemergence (POST) herbicide programs on GR Palmer amaranth control in Roundup Ready 2 Xtend soybean. The study site at Hays was infested with GR Palmer amaranth population prior to soybean planting; whereas, the Manhattan site had natural …

Efficacy Of Zest Application Timings In Irrigated Acetolactase Synthase-Resistant Grain Sorghum, R. S. Currie, P. W. Geier

Kansas Agricultural Experiment Station Research Reports

Acetolactase synthase inhibiting (ALS) herbicides were evaluated for efficacy in ALS-resistant grain sorghum. Kochia and quinoa control were similar among all herbicides tested regardless of evaluation date. Cinch ATZ alone preemergence, and Cinch plus Resolve and Harmony GT PRE followed by Zest POST controlled puncturevine 73-78%. Late-season green foxtail control was best when Zest was included as an early postemergence or postemergence application. Cinch ATZ applied alone preemergence, Cinch ATZ preemergence followed by Zest POST, and Cinch plus Resolve and Harmony GT PRE followed by Zest POST controlled Palmer amaranth 81–84%, and resulted in the highest grain yields.

Zest Efficacy And Crop Response In Two Acetolactase Synthase-Tolerant Grain Sorghum Hybrids, R. S. Currie, P. W. Geier

Kansas Agricultural Experiment Station Research Reports

Two ALS-tolerant grain sorghum hybrids were evaluated for efficacy and crop tolerance to Zest (nicosulfuron). Weed control and crop response in two herbicide-tolerant sorghum hybrids were similar. All herbicides controlled kochia, common sunflower, velvetleaf, and quinoa well. Palmer amaranth control was inadequate when no preemergence (PRE) herbicide was applied. Puncturevine and green foxtail control was 90% or more with all Zest (nicosulfuron) treatments applied early postemergence (EPOST) or postemergence (POST). Sorghum injury from the Zest treatments was minor and transient. Relative to the untreated controls, grain yields were greater when a PRE or PRE followed by POST program was used. …

Application Timing Efficacy Of Enlist Duo In Irrigated Corn, R. S. Currie, P. W. Geier

Kansas Agricultural Experiment Station Research Reports

In this study, herbicides were tested to compare application timing for weed control in irrigated corn. All herbicides tested provided season-long control (90% or more) of Palmer amaranth, Russian thistle, quinoa, and common sunflower. The inclusion of Enlist Duo to SureStart II as an early postemergence (V2) treatment increased kochia and johnsongrass control compared to a preemergence treatment of SureStart II alone early in the season. However, by later in the year, control of kochia and johnsongrass was best when Enlist Duo application was delayed until the V4 stage. Enlist Duo provided equal control of all weeds when applied at …

Comparisons Of Terbuthylazine And Atrazine Rates And Tank Mixtures In Irrigated Corn, R. S. Currie, P. W. Geier

Kansas Agricultural Experiment Station Research Reports

A comparison of terbuthylazine and atrazine rates alone and in combination with other herbicides in corn was conducted. All herbicides controlled Russian thistle and common sunflower by 90% or more. Preemergence control of green foxtail required a tank mixture of mesotrione (Stalwart C, Stalwart 3W, SA-0070128, and SA-0070129) with terbuthylazine or atrazine to be effective. Both terbuthylazine and atrazine alone provided similar kochia control, but control tended to increase with the addition of mesotrione. Palmer amaranth control was similar among terbuthylazine rates early in the season, but increased as atrazine rate increased. Crabgrass control increased as terbuthylazine rate increased early …

Liberty Compared To Glyphosate Products In Irrigated Corn, R. S. Currie, P. W. Geier

Kansas Agricultural Experiment Station Research Reports

Postemergence treatments of Liberty (glufosinate) were compared to Durango DMA and Roundup PowerMax (glyphosate) after various preemergence treatments for efficacy in corn. Control of common sunflower, green foxtail, Russian thistle, and quinoa exceeded 92% regardless of herbicide treatment or evaluation date. Similarly, all preemergence (PRE) treatments controlled Palmer amaranth, kochia, and crabgrass by 93% or more. Later in the season, control of kochia was slightly less when Verdict (saflufenacil/dimethenamid) and atrazine PRE was followed by Roundup PowerMax and atrazine postemergence (POST). Palmer amaranth and crabgrass control was less when Verdict and atrazine PRE was followed by Roundup PowerMax or Liberty …

Anthem Maxx Tank Mixture Comparisons In Irrigated Corn, R. S. Currie, P. W. Geier

Kansas Agricultural Experiment Station Research Reports

The use of multiple herbicide modes of action in single versus sequential applications was examined for efficacy in corn. Common sunflower control was complete with all early postemergence and postemergence herbicides late in the season. Control of Russian thistle, Palmer amaranth, and green foxtail were 95% or more with all early postemergence and postemergence herbicides except Halex GT. All herbicide treatments increased grain yield 15–33% compared to the nontreated controls except Halex GT applied early postemergence.

Vida Alone And In Tank Mixtures For Kochia Control In Fallow, R. S. Currie, P. W. Geier

Kansas Agricultural Experiment Station Research Reports

To learn more about kochia control in fallow, a comparison of Vida alone and in tank mixtures was conducted. Glyphosate alone provided no more than 40% kochia control, and was similar to Vida or 2,4-D alone late in the season. The tank mixture of Vida plus Gramoxone and Spartan controlled kochia the best regardless of rating date, and was the only treatment to provide more than 95% control at 28 days.

Comparisons Of Acuron, Surestart Ii, And Valor For Residual Weed Control In Grain Sorghum, R. S. Currie, P. W. Geier

Kansas Agricultural Experiment Station Research Reports

Herbicides were compared to standard treatments for preplant efficacy and crop response in grain sorghum. All herbicides controlled buffalobur and velvetleaf similarly late in the season. SureStart II and Acuron provided the best Palmer amaranth, puncturevine, and green foxtail control. Valor at 1 or 2 oz/a provided less than 70% puncturevine and green foxtail control late in the season. Only minimal visual injury was observed, and all herbicides increased sorghum yield 47–122% relative to the untreated controls.