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Cation Exchange Resins As Indicator Of In-Season Potassium Supply For Soybean In Kansas, D. A. Charbonnier, M. J. Coelho, D. A. Ruiz Diaz

Kansas Agricultural Experiment Station Research Reports

The use of ion-exchange resins to measure soil nutrient availability has potential applications for fertilizer recommendations. The objective of this study was to evaluate the relationship between potassium (K) adsorption by cation exchange resins (CER) and K uptake by soybean in field conditions. The study was conducted at two locations in Kansas during 2019. Two treatments were selected to evaluate the CER. Treatments included a check (0 lb K₂O/a) and a high K rate with 150 lb K₂O/a applied pre-plant and incorporated. The Plant Root Simulator (PRS, Western Ag Innovations, Saskatchewan, Canada) was used as an …

Kansas Fertilizer Research 2020, D. A. Ruiz Diaz

Kansas Agricultural Experiment Station Research Reports

A summary of research conducted in 2018-2020 on fertilizer use and management practices for crops in Kansas. Published in 2020 from the Kansas State University Agricultural Experiment Station and Cooperative Extension Servicehttps://www.ag.k-state.edu/.

Understanding Soybean Root Microbiome Assembly Along Its Development From Both Plant And Soil Perspectives, Fang Liu

Doctoral Dissertations

Plants have evolved intimate partnerships with microorganisms to compensate for their sessile nature and to respond to changing biotic and abiotic environmental conditions. The plant-associated microbiome greatly expands plant functions and plasticity via improved nutrient availability/uptake, enhancing plant abiotic stress tolerance, and promoting plant defense. Understanding plant microbiome assembly is crucial for leveraging their versatile benefits to the plant host and advancing the next green movement in sustainable agriculture. In this study, we comprehensively characterized soybean root-associated microbiome assembly via the 16S rRNA gene and ITS2 (internal transcribed spacer) region amplicon sequencing. Using this technology, we examined different factors influencing …

Best Management Practices Of Non-Irrigated Soybean (Glycine Max) Production Systems In The Mid-South, Daniel Zachary Reynolds

Theses and Dissertations

Experiments were conducted to evaluate the most profitable and effective management practices for non-irrigated soybean production. Common production practices were compared side by side to evaluate yield response and economic returns. Combinations of row spacings and planting dates were evaluated to determine interactions between the two factors and also the effects on yield. Lastly, the effectiveness of various iron sources was examined in iron deficiency chlorosis (IDC) susceptible soybeans when applied foliar, inurrow at planting, and a split application. These data suggest that in non-irrigated soybeans, “low input management” practices do not maximize yields, but can be more profitable, depending …

The Effects Of Seed-Applied Fluopyram On Root Penetration And Development Of Meloidogyne Incognita On Cotton And Soybean, Tracy Hawk

Graduate Theses and Dissertations

Plant-parasitic nematodes are major pests of cotton and soybean in Arkansas, and across the Southern United States. These nematodes cause more than $3 billion worth of crop losses each year, in part due to lack of available control tactics, such as nematicides. Fluopyram has recently been registered as a seed-treatment nematicide in agronomic crops. The toxicity of fluopyram against Meloidogyne incognita infection has been reported, however, information on root protection provided by fluopyram against Meloidogyne incognita is lacking. The first objective of this research was to evaluate the effect seed-applied fluopyram had on nematode development, root galling, and reproduction on …

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 …

Arkansas Soybean Research Studies 2018, Jeremy Ross

Arkansas Agricultural Experiment Station Research Series

Arkansas is the leading soybean-producing state in the mid-southern United States. Arkansas ranked 11th in soybean production in 2018 when compared to the other soybean-producing states in the U.S. The state represents 3.7% of the total U.S. soybean production and 3.7% of the total acres planted in soybean in 2018. The 2018 state soybean average was 50.5 bushels per acre, half a bushel lower than the state record set in 2017. The top five soybean-producing counties in 2018 were Mississippi, Desha, Phillips, Arkansas, and Poinsett Counties (Table 1). These five counties accounted for 33.7% of soybean production in Arkansas in …

Arkansas Soybean Performance Tests 2019, J. F. Carlin, R. D. Bond, J. A. Still

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’s 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.

Understanding Nitrogen Limitation In Soybean, Nicolas Cafaro La Menza

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

Meeting soybean demand on existing cropland area for a global population of 9.7 billion people by the year 2050 requires narrowing the existing gap between average producer yield and yield potential. Soybean relies on two sources on nitrogen (N): biological N2 fixation and indigenous soil N supply. As soybean yield continues to increase, it seems critical to know if there is a yield level at which potential contribution of indigenous nitrogen sources and fixation becomes insufficient to meet crop N requirements for high yields, while still maintaining or increasing protein and oil concentration. This study evaluated N limitation across 29 …

Integration Of Cover Crops Into Midwest Corn-Soybean Cropping Systems And Potential For Weed Suppression, Joshua S. Wehrbein

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

Cover crops have potential to provide benefits to agricultural systems, such as improved soil productivity, nutrient scavenging, weed suppression, and livestock forage. There are several challenges associated with cover crop integration into traditional Midwest corn-soybean cropping systems. One of these challenges is timely establishment in the fall, which is limited by the relatively late harvest of corn and soybean. Cover crop effectiveness is related to the amount of biomass produced, thus maximizing the growth period in the fall is desired. To address this challenge, we evaluated the potential to utilize early-season soybean maturity groups (MGs) to allow for earlier soybean …

Glycerol-3-Phosphate Mediates Rhizobia-Induced Systemic Signaling In Soybean, M. B. Shine, Qing-Ming Gao, R. V. Chowda-Reddy, Asheesh K. Singh, Pradeep Kachroo, Aardra Kachroo

Plant Pathology Faculty Publications

Glycerol-3-phosphate (G3P) is a well-known mobile regulator of systemic acquired resistance (SAR), which provides broad spectrum systemic immunity in response to localized foliar pathogenic infections. We show that G3P-derived foliar immunity is also activated in response to genetically-regulated incompatible interactions with nitrogen-fixing bacteria. Using gene knock-down we show that G3P is essential for strain-specific exclusion of non-desirable root-nodulating bacteria and the associated foliar pathogen immunity in soybean. Grafting studies show that while recognition of rhizobium incompatibility is root driven, bacterial exclusion requires G3P biosynthesis in the shoot. Biochemical analyses support shoot-to-root transport of G3P during incompatible rhizobia interaction. We describe …

Evaluation Of Soil Type And Seeding Rate On Winter Cover Crop Species In A Soybean Production System, Donna S. Morgan

LSU Doctoral Dissertations

The integration of winter annual cover crops into a cropping system can potentially improve soil health and crop production, however, the impact of variables such as seeding rates, across two very different soil types, has not been well documented. A two-year study was conducted at the Dean Lee Research Station and Extension Center in Alexandria, Louisiana to evaluate the effects of cover crop seeding rate and soil type on cover crop biomass, weed suppression, soil fertility, and soybean (Glycine max L) growth and yield. Analysis of potential economic impacts was also performed to estimate financial net returns for three …

Regenerating Agricultural Landscapes With Perennial Groundcover For Intensive Crop Production, Kenneth J. Moore, Robert P. Anex, Amani E. Elobeid, Shuizhang Fei, Cornelia B. Flora, A. Susana Goggi, Keri L. Jacobs, Prashant Jha, Amy L. Kaleita, Douglas L. Karlen, David A. Laird, Andrew W. Lenssen, Thomas Lubberstedt, Marshall D. Mcdaniel, D. Raj Raman, Sharon L. Weyers

Douglas L Karlen

The Midwestern U.S. landscape is one of the most highly altered and intensively managed ecosystems in the country. The predominant crops grown are maize (Zea mays L.) and soybean [Glycine max (L.) Merr]. They are typically grown as monocrops in a simple yearly rotation or with multiple years of maize (2 to 3) followed by a single year of soybean. This system is highly productive because the crops and management systems have been well adapted to the regional growing conditions through substantial public and private investment. Furthermore, markets and supporting infrastructure are highly developed for both crops. As maize and …

Characterization Of Xylaria Sp., The Causal Agent Of Taproot Decline In Mississippi Soybean, Hope Becton

Theses and Dissertations

Taproot decline (TRD), caused by an undescribed species of Xylaria, is an emerging root disease of soybean in Mississippi. Xylaria sp. isolates were collected from soybean roots and used to characterize TRD distribution as well as optimal growth temperature, pathogenicity, alternative host range, in vitro pathogenicity, and fungicide sensitivity. The 24 selected Xylaria sp. isolates from the 2016 collection had a mean optimal growth temperature of 26.7°C, and were pathogenic to soybean; however, differences in virulence occurred among isolates. Five selected Xylaria sp. isolates produced stroma on six hosts: corn, cotton, peanut, rice, sorghum, and wheat. Xylaria sp. colonized corn, …

Agronomic Management Of Flooded Soybean In Mississippi Delta, William Lassiter

Theses and Dissertations

Flooding is a major obstacle for soybean production in the Mississippi Delta. One management practice that soybean producers use to mitigate the effects of flooding is planting soybean on raised beds. Another potential management practice that could be employed in the Mississippi Delta is the use of flood tolerant soybean cultivars. Therefore, the objective of this study was to evaluate the effectiveness of raised beds for flooding management and compare the tolerance of six soybean cultivars under flooded conditions at multiple growth stages and flood durations. Field studies were established during the 2017 and 2018 growing seasons at the Mississippi …

Impact Of Early Season Insect Management Decisions On Yield Of Soybean, John Hartley North

Theses and Dissertations

To determine the optimal seeding rate and utilization of seed treatment combinations for maximizing soybean yield within optimal and late planting dates. Also, experiments were conducted to quantify effects of soybean stand loss and to determine optimal seeding rates at various planting dates comparing three seed treatments. Experiments were conducted to test influence of planter type and seeding rate on soybean. Soybean seed treated with at planting insecticides showed no difference in yield compared to fungicide only treated seed. Also, yields were maximized at low seeding rates where no stand loss occurred. Soybean yields benefited from where seeding rates were …

Varietal And Residual Soil Test K Level Effects On Soybean Leaf K Status And Yield, Andrew Dygert

Theses and Dissertations

Newer multi-trait soybean varieties have resulted in greater yields, bringing into question whether current soil test K (STK) correlation, calibration, and recommendations need updating to maximize yield. The objective of this study was to refine soil test correlation and calibration using a range in residual STK levels and response in temporal leaf and seed K concentrations and yield across soybean maturity groups IV and V. For the 0- to 15-cm soil depth STK levels greater than 125 mg K kg-1, K did not limit yield. Critical tissue K varied between years and maturity group. Critical K at R1, R3, and …

Studies On Pathogenesis Of The Diseases Caused By Macrophomina Phaseolina And Phomopsis Longicolla On Soybean, Marcio Leizer Zaccaron

Graduate Theses and Dissertations

Soybean (Glycine max), a legume, is an economically important crop in many parts of the world, including the USA, Brazil, Argentina, China, and India, currently the top five producing countries. Soybean is primarily used as feed, with incising markets for food and biodiesel. Similar to most crops, soybean yield and quality are affected by a diverse group of plant pathogens. In particular, several species of filamentous fungi have been the cause of severe yield losses in most growing regions world-wide. The soil born fungus Macrophomina phaseolina, causal agent of charcoal rot, has been found to be endemic to several soybean …

Mid To Late Season Weed Detection In Soybean Production Fields Using Unmanned Aerial Vehicle And Machine Learning, Arun Narenthiran Veeranampalayam Sivakumar

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Mid-late season weeds are those that escape the early season herbicide applications and those that emerge late in the season. They might not affect the crop yield, but if uncontrolled, will produce a large number of seeds causing problems in the subsequent years. In this study, high-resolution aerial imagery of mid-season weeds in soybean fields was captured using an unmanned aerial vehicle (UAV) and the performance of two different automated weed detection approaches – patch-based classification and object detection was studied for site-specific weed management. For the patch-based classification approach, several conventional machine learning models on Haralick texture features were …

Developing Management Strategies For Taproot Decline, Xylaria Sp., In Soybean, Myra Purvis

LSU Master's Theses

Soybean (Glycine max) is one of the most important oilseed crops in the world. Taproot decline is a recently discovered disease caused by Xylaria sp., a novel species located within the Xylaria arbuscula aggregate. Foliar symptoms include interveinal chlorosis and necrosis, and upon further investigation, there are often dead plants adjacent within the row. Many other soybean diseases have similar foliar symptoms; therefore, more examination is usually required for proper identification. Soybean debris from previous years is suspected to be the primary source of inoculum. Plants may be infected at any point during the growing season, often …

Developing Management Strategies For Taproot Decline, Xylaria Sp., In Soybean, Myra Purvis

Myra Purvis

Developing Management Strategies For Taproot Decline , Xylaria Sp., In Soybean, Myra Purvis

Myra Purvis

Rapid Profiling Of Soybean Aromatic Compounds Using Electronic Nose, Ramasamy Ravi, Ali Taheri, Durga Khandekar, Reneth Millas

Agricultural and Environmental Sciences Faculty Research

Soybean (Glycine max (L.)) is the world’s most important seed legume, which contributes to 25% of global edible oil, and about two-thirds of the world’s protein concentrate for livestock feeding. One of the factors that limit soybean’s utilization as a major source of protein for humans is its characteristic soy flavor. This off-flavor can be attributed to the presence of various chemicals such as phenols, aldehydes, ketones, furans, alcohols, and amines. In addition, these flavor compounds interact with protein and cause the formation of new off-flavors. Hence, studying the chemical profile of soybean seeds is an important step in understanding …

Impact Of Preventative Fungicide Practices On Mid-South Soybean (Glycine Max) Grain Development, Quality, And Economic Return, Chase Alan Floyd

Theses and Dissertations

The need for profitable soybean production practices gain continually with increasing input costs and reduced profit margins. Constant cultivar and product developments has resulted in limited current data available regarding the profitability of preventative fungicide applications and physiological benefits that can occur from these applications. Research was conducted during 2017 and 2018 to determine optimal fungicide application timing, while assessing multiple fungicide options and resulting effect on soybean grain yield, seed quality, and profitability. Additional research was conducted to determine optimal row spacing, planting date and fungicide application combinations to maximize soybean production profitability. These data suggest using multi-mode of …

Crop Planning In Sustainable Agriculture: Dynamic Farmland Allocation In The Presence Of Crop Rotation Benefits, Onur Boyabatli, Javad Nasiry, Yangfang (Helen) Zhou

Research Collection Lee Kong Chian School Of Business

This paper examines crop planning decision in sustainable agriculture---that is, how to allocate farmland among multiple crops in each growing season when the crops have rotation benefits across growing seasons. We consider a farmer who periodically allocates the farmland between two crops in the presence of revenue uncertainty where revenue is stochastically larger and farming cost is lower when a crop is grown on rotated farmland (where the other crop was grown in the previous season). We characterize the optimal dynamic farmland allocation policy and perform sensitivity analysis to investigate how revenue uncertainty of each crop affects the farmer's optimal …

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 …

Spatial Patterns And Sequential Sampling Plans For Estimating Densities Of Stink Bugs (Hemiptera: Pentatomidae) In Soybean In The North Central Region Of The United States, Daniela T. Pezzini, Christina D. Difonzo, Deborah L. Finke, Thomas Hunt, Janet J. Knodel, Christian H. Krupke, Brian P. Mccornack, Andrew P. Michel, Roger D. Moon, Christopher R. Philips, Adam J. Varenhorst, Robert Wright, Robert Koch

Department of Entomology: Faculty Publications

Stink bugs are an emerging threat to soybean (Fabales: Fabaceae) in the North Central Region of the United States. Consequently, region-specific scouting recommendations for stink bugs are needed. The aim of this study was to characterize the spatial pattern and to develop sampling plans to estimate stink bug population density in soybean fields. In 2016 and 2017, 125 fields distributed across nine states were sampled using sweep nets. Regression analyses were used to determine the effects of stink bug species [Chinavia hilaris (Say) (Hemiptera: Pentatomidae) and Euschistus spp. (Hemiptera: Pentatomidae)], life stages (nymphs and adults), and field locations (edge …

Uncovering A Mystery Of The Isoflavonoid Metabolon: Identification And Characterization Of The Arogenate Dehydratase Gene Family In Soybean, Kelsey Pannunzio

Electronic Thesis and Dissertation Repository

Soybean (Glycine max) is a vastly important, multi-billion dollar global commodity; but this crop’s yields are under threat from the pathogen Phytophthora sojae, which causes extensive stem and root rot in soybean crops. Isoflavonoids, a metabolite class unique to legumes, are a promising research target to combat P. sojae. Isoflavonoids are released as phytoalexins in response to stress, and also facilitate interactions with nitrogen-fixing rhizobial bacteria through nodule formation. An isoflavonoid biosynthesis metabolon was discovered in soybean through co-immunoprecipitation, anchored to the endoplasmic reticulum by isoflavone synthase (IFS) and Cinnamate 4-hydroxylase, two cytochrome P450 enzymes. One of the …

Impact Of Planting Date And Variety On Soybean Yield, Heather Darby, Sara Ziegler, Ivy Krezinski, Rory Malone

Northwest Crops & Soils Program

In 2019, the University of Vermont Extension Northwest Crops and Soils Program investigated the impact of planting date and variety on soybean yield and quality at Borderview Research Farm in Alburgh, VT. Soybeans can be grown for human consumption, animal feed, and biodiesel. Livestock farmers are interested in producing more of their own grains and as a result, soybean acreage in Vermont is increasing. Given the short growing season in Vermont, it is important to understand optimum planting dates to obtain the highest yields. In an effort to support and expand the local soybean market throughout the northeast, the University …

Conventional Soybean Variety Trial, Heather Darby, Sara Ziegler, Ivy Krezinski, Rory Malone

Northwest Crops & Soils Program

In 2019, the University of Vermont Extension Northwest Crops and Soils Team evaluated yield and quality of short season soybean varieties at Borderview Research Farm in Alburgh, VT. Soybeans are grown for human consumption, animal feed, and biodiesel. As farmers look to reduce feed costs or diversify markets, soybean acreage across Vermont is increasing. Local research is needed to identify varieties that are best adapted to this region. In an effort to support and expand the local soybean market throughout the northeast, the University of Vermont Extension Northwest Crop and Soils (NWCS) Program, as part of a grant from the …