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2021

Agronomy and Crop Sciences

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Full-Text Articles in Life Sciences

Domestication Reshaped The Genetic Basis Of Inbreeding Depression In A Maize Landrace Compared To Its Wild Relative, Teosinte, Luis Fernando Samayoa, Bode A. Olukolu, Chin Jian Yang, Qiuyue Chen, Markus G. Stetter, Alessandra M. York, Jose De Jesus Sanchez-Gonzalez, Jeffrey C. Glaubitz, Peter J. Bradbury, Maria Cinta Romay, Qi Sun, Jinliang Yang, Jeffrey Ross-Ibarra, Edward S. Buckler, John F. Doebley, James B. Holland Dec 2021

Domestication Reshaped The Genetic Basis Of Inbreeding Depression In A Maize Landrace Compared To Its Wild Relative, Teosinte, Luis Fernando Samayoa, Bode A. Olukolu, Chin Jian Yang, Qiuyue Chen, Markus G. Stetter, Alessandra M. York, Jose De Jesus Sanchez-Gonzalez, Jeffrey C. Glaubitz, Peter J. Bradbury, Maria Cinta Romay, Qi Sun, Jinliang Yang, Jeffrey Ross-Ibarra, Edward S. Buckler, John F. Doebley, James B. Holland

Department of Agronomy and Horticulture: Faculty Publications

Inbreeding depression is the reduction in fitness and vigor resulting from mating of close relatives observed in many plant and animal species. The extent to which the genetic load of mutations contributing to inbreeding depression is due to large-effect mutations versus variants with very small individual effects is unknown and may be affected by population history. We compared the effects of outcrossing and self-fertilization on 18 traits in a landrace population of maize, which underwent a population bottleneck during domestication, and a neighboring population of its wild relative teosinte. Inbreeding depression was greater in maize than teosinte for 15 of …


Identification Of Candidate Genes And Genomic Regions Associated With Adult Plant Resistance To Stripe Rust In Spring Wheat, Amira M. I. Mourad, Mohamed A. Abou-Zeid, Shamseldeen Eltaher, P. Stephen Baenziger, Andreas Börner Dec 2021

Identification Of Candidate Genes And Genomic Regions Associated With Adult Plant Resistance To Stripe Rust In Spring Wheat, Amira M. I. Mourad, Mohamed A. Abou-Zeid, Shamseldeen Eltaher, P. Stephen Baenziger, Andreas Börner

Department of Agronomy and Horticulture: Faculty Publications

Wheat stripe rust (caused by Puccinia striiformis f. sp. tritici) is a major disease that damages wheat plants and affects wheat yield all over the world. In recent years, stripe rust became a major problem that affects wheat yield in Egypt. New races appeared and caused breakdowns in the resistant genotypes. To improve resistance in the Egyptian genotypes, new sources of resistance are urgently needed. In the recent research, a set of 95 wheat genotypes collected from 19 countries, including Egypt, were evaluated for their resistance against the Egyptian race(s) of stripe rust under field conditions in the two …


Relationships Among College-Level Science Course Enrollment, Environmental Perception, And Pro-Environmental Attitude: Evidence From The Us General Social Survey, Mazbahul G. Ahamad, Fahian Tanin Dec 2021

Relationships Among College-Level Science Course Enrollment, Environmental Perception, And Pro-Environmental Attitude: Evidence From The Us General Social Survey, Mazbahul G. Ahamad, Fahian Tanin

Department of Agronomy and Horticulture: Faculty Publications

Understanding pro-environmental attitudes is critical to encouraging pollution-minimizing behaviors. Therefore, identifying associated factors is essential for understanding different types of pro-environmental attitudes. We aimed to investigate the associations among individuals’ college-level science course enrollment and their perceptions of the level of spending to improve and protect the environment, as well as their pro-environmental attitudes. We used nationwide population-based cross-sectional survey data from 2,348 individuals obtained from the General Social Survey in the United States. An ordered logistic model was used to examine the associations among college-level science course enrollment, environmental perception, and pro-environmental attitude. We found that science course enrollment …


Bases For The Establishment Of Robusta Coffee (Coffea Canephora) As A New Crop For Colombia, Luis F. Campuzano-Duque, Juan Carlos Herrera, Claire Ged, Matthew Wohlgemuth Blair Dec 2021

Bases For The Establishment Of Robusta Coffee (Coffea Canephora) As A New Crop For Colombia, Luis F. Campuzano-Duque, Juan Carlos Herrera, Claire Ged, Matthew Wohlgemuth Blair

Agricultural and Environmental Sciences Faculty Research

Robusta coffee (C. canephora) covers 36% of world coffee production and has strategic relevance as a beverage that it is produced by thousands of small-scale producers around the world. Although mainly grown in Africa and Asia as opposed to Latin America, this situation is changing. Colombia is recognized as a producer of high-quality Arabica (C. arabica L.) coffee, however we argue that Robusta represents a great economic opportunity for small scale producers, for the industrialization of new products and for emerging coffee chains. Therefore, the objective of this review is to outline the agronomic value of Robusta coffee as a …


Cold Conditioned: Discovery Of Novel Alleles For Low-Temperature Tolerance In The Vavilov Barley Collection, Ahmad H. Sallam, Kevin P. Smith, Gongshe Hu, Jamie Sherman, Peter Stephen Baeziger, Jochum Wiersma, Carl Duley, Eric J. Stockinger, Mark E. Sorrells, Tamas Szinyei, Igor G. Loskutov, Olga N. Kovaleva, Jed Eberly, Brian J. Steffenson Dec 2021

Cold Conditioned: Discovery Of Novel Alleles For Low-Temperature Tolerance In The Vavilov Barley Collection, Ahmad H. Sallam, Kevin P. Smith, Gongshe Hu, Jamie Sherman, Peter Stephen Baeziger, Jochum Wiersma, Carl Duley, Eric J. Stockinger, Mark E. Sorrells, Tamas Szinyei, Igor G. Loskutov, Olga N. Kovaleva, Jed Eberly, Brian J. Steffenson

Department of Agronomy and Horticulture: Faculty Publications

Climate changes leading to higher summer temperatures can adversely affect cool season crops like spring barley. In the Upper Midwest region of the United States, one option for escaping this stress factor is to plant winter or facultative type cultivars in the autumn and then harvest in early summer before the onset of high-temperature stress. However, the major challenge in breeding such cultivars is incorporating sufficient winter hardiness to survive the extremely low temperatures that commonly occur in this production region. To broaden the genetic base for winter hardiness in the University of Minnesota breeding program, 2,214 accessions from the …


Evaluation Of Alternate Wetting And Drying Irrigation Management In Rice, Richard Lee Atwill Ii Dec 2021

Evaluation Of Alternate Wetting And Drying Irrigation Management In Rice, Richard Lee Atwill Ii

Theses and Dissertations

Water level declines in the Mississippi River Valley Alluvial Aquifer (MRVAA) are attributed largely to withdrawals for rice (Oryza sativa L.) irrigation. This study was performed to determine if alternative irrigation strategies for rice could reduce withdrawal from the MRVAA without having an adverse effect on grain yield, grain quality, control of barnyardgrass, and profitability. Research was conducted in Stoneville, MS and 19 on-farm locations across the Delta region of Mississippi from 2014 through 2017 to determine the irrigation threshold for alternate wetting and drying (AWD) rice irrigation, the effect of AWD management on barnyardgrass control, and effects of …


Sustainable Intensification For A Larger Global Rice Bowl, Shen Yuan, Bruce A. Linquist, Lloyd T. Wilson, Kenneth G. Cassman, Alexander M. Stuart, Valerien Pede, Berta Miro, Kazuki Saito, Nurwulan Agustiani, Vina Eka Aristya, Leonardus Y. Krisnadi, Alencar Junior Zanon, Alexandre Bryan Heinemann, Gonzalo Carracelas, Nataraja Subash, Pathula S. Brahmanand, Tao Li, Shaobing Peng, Patricio Grassini Dec 2021

Sustainable Intensification For A Larger Global Rice Bowl, Shen Yuan, Bruce A. Linquist, Lloyd T. Wilson, Kenneth G. Cassman, Alexander M. Stuart, Valerien Pede, Berta Miro, Kazuki Saito, Nurwulan Agustiani, Vina Eka Aristya, Leonardus Y. Krisnadi, Alencar Junior Zanon, Alexandre Bryan Heinemann, Gonzalo Carracelas, Nataraja Subash, Pathula S. Brahmanand, Tao Li, Shaobing Peng, Patricio Grassini

Department of Agronomy and Horticulture: Faculty Publications

Future rice systems must produce more grain while minimizing the negative environmental impacts. A key question is how to orient agricultural research & development (R&D) programs at national to global scales to maximize the return on investment. Here we assess yield gap and resource-use efficiency (including water, pesticides, nitrogen, labor, energy, and associated global warming potential) across 32 rice cropping systems covering half of global rice harvested area. We show that achieving high yields and high resource-use efficiencies are not conflicting goals. Most cropping systems have room for increasing yield, resource-use efficiency, or both. In aggregate, current total rice production …


Hyperseed: An End-To-End Method To Process Hyperspectral Images Of Seeds, Tian Gao, Anil Kumar Nalini Chandran, Puneet Paul, Harkamal Walia, Hongfeng Yu Dec 2021

Hyperseed: An End-To-End Method To Process Hyperspectral Images Of Seeds, Tian Gao, Anil Kumar Nalini Chandran, Puneet Paul, Harkamal Walia, Hongfeng Yu

School of Computing: Faculty Publications

High-throughput, nondestructive, and precise measurement of seeds is critical for the evaluation of seed quality and the improvement of agricultural productions. To this end, we have developed a novel end-to-end platform named HyperSeed to provide hyperspectral information for seeds. As a test case, the hyperspectral images of rice seeds are obtained from a high-performance line-scan image spectrograph covering the spectral range from 600 to 1700 nm. The acquired images are processed via a graphical user interface (GUI)-based open-source software for background removal and seed segmentation. The output is generated in the form of a hyperspectral cube and curve for each …


Climate And Agronomy, Not Genetics, Underpin Recent Maize Yield Gains In Favorable Environments, Gonzalo Rizzo, Juan Pablo Monzon, Fatima Amor Tenorio, Réka Howard, Kenneth G. Cassman, Patricio Grassini Dec 2021

Climate And Agronomy, Not Genetics, Underpin Recent Maize Yield Gains In Favorable Environments, Gonzalo Rizzo, Juan Pablo Monzon, Fatima Amor Tenorio, Réka Howard, Kenneth G. Cassman, Patricio Grassini

Department of Agronomy and Horticulture: Faculty Publications

Quantitative understanding of factors driving yield increases of major food crops is essential for effective prioritization of research and development. Yet previous estimates had limitations in distinguishing among contributing factors such as changing climate and new agronomic and genetic technologies. Here, we distinguished the separate contribution of these factors to yield advance using an extensive database collected from the largest irrigated maize-production domain in the world located in Nebraska (United States) during the 2005-to-2018 period. We found that 48% of the yield gain was associated with a decadal climate trend, 39% with agronomic improvements, and, by difference, only 13% with …


Arkansas Corn And Grain Sorghum Performance Tests 2021, J. F. Carlin, R. B. Morgan, R. D. Bond Dec 2021

Arkansas Corn And Grain Sorghum Performance Tests 2021, J. F. Carlin, R. B. Morgan, R. D. Bond

Arkansas Agricultural Experiment Station Research Series

Corn and grain sorghum performance tests are conducted each year in Arkansas by the University of Arkansas System Division of Agriculture. The tests provide information to companies marketing seed within the state and aid the Arkansas Cooperative Extension Service in formulating recommendations for producers. The 2021 corn performance tests contained 70 hybrids and were conducted at the Northeast Research and Extension Center (NEREC) at Keiser, the Lon Mann Cotton Research Station (LMCRS) near Marianna, the Bell Farming Company (BFC) near Des Arc, the Rohwer Research Station (RRS) near Rohwer, and the Rice Research and Extension Center (RREC) near Stuttgart. The …


South Dakota Farmers’ Perceived Extreme Weather Frequency And Adaptation Measures, Tong Wang, Jim Ristau Dec 2021

South Dakota Farmers’ Perceived Extreme Weather Frequency And Adaptation Measures, Tong Wang, Jim Ristau

South Dakota Farm Survey

Researchers at South Dakota State University (SDSU) conducted surveys of eastern South Dakota (SD) commodity crop producers with the support of the South Dakota Corn Utilization Council. Using publicly available addresses of government program participants, a random sample of 3,000 producers were sent the survey in 2018. 650 were ineligible and 708 responded to the survey for a response rate of 30%. In 2021, the same producers who took the survey in 2018 were asked to take a follow up survey. 94 were ineligible, and 350 responded for a 59% response rate. Producers could take the survey online or via …


South Dakota Farmers’ Usage Of Integrated Crop & Livestock Management, Tong Wang, Jim Ristau Dec 2021

South Dakota Farmers’ Usage Of Integrated Crop & Livestock Management, Tong Wang, Jim Ristau

South Dakota Farm Survey

Researchers at South Dakota State University (SDSU) conducted producer surveys in the eastern part of South Dakota in both 2018 and 2021. Producers could take the survey online or via mail and were asked questions about their farm, farming practices including usage of soil and water conservation practices, and their values. Using publicly available addresses from the Farm Service Agency, a random sample of 3,000 producers were sent the survey in 2018. 650 were ineligible, and 708 responded to the survey for a response rate of 30%. In 2021, the same producers who took the survey in 2018 were asked …


South Dakota Farmer Survey Chemical Use On Cropland, Tong Wang, Jim Ristau Dec 2021

South Dakota Farmer Survey Chemical Use On Cropland, Tong Wang, Jim Ristau

South Dakota Farm Survey

Researchers at South Dakota State University (SDSU) conducted surveys with South Dakota (SD) commodity crop producers in the eastern part of the state in both 2018 and 2021. Producers could take the survey online or via mail and were asked questions about their farm, farming practices including usage of soil and water conservation practices, challenges, and benefits to using conservation practices, and their attitudes about the environment. Using publicly available addresses from the Farm Service Agency of government program participants, a random sample of 3,000 producers were sent the survey in 2018. 650 were ineligible, and 708 responded to the …


South Dakota Farmers’ Usage Of Cover Crops, Tong Wang, Jim Ristau Dec 2021

South Dakota Farmers’ Usage Of Cover Crops, Tong Wang, Jim Ristau

South Dakota Farm Survey

Researchers at South Dakota State University (SDSU) conducted producer surveys in the eastern part of South Dakota in both 2018 and 2021. Producers could take the survey online or via mail and were asked questions about their farm, farming practices including usage of soil and water conservation practices, and their values. Using publicly available addresses from the Farm Service Agency, a random sample of 3,000 producers were sent the survey in 2018. 650 were ineligible, and 708 responded to the survey for a response rate of 30%. In 2021, the same producers who took the survey in 2018 were asked …


South Dakota Farmers’ Usage Of Diversified Crop Rotations, Tong Wang, Jim Ristau Dec 2021

South Dakota Farmers’ Usage Of Diversified Crop Rotations, Tong Wang, Jim Ristau

South Dakota Farm Survey

Researchers at South Dakota State University (SDSU) conducted producer surveys in the eastern part of South Dakota in both 2018 and 2021. Producers could take the survey online or via mail and were asked questions about their farm, soil and water conservation practices, and their values. Using publicly available addresses from the Farm Service Agency, a random sample of 3,000 producers were sent the survey in 2018. 650 were ineligible, and 708 responded to the survey for a response rate of 30%. In 2021, the same producers who took the survey in 2018 were asked to take a follow up …


Comparing Machine Learning Techniques With State-Of-The-Art Parametric Prediction Models For Predicting Soybean Traits, Susweta Ray Dec 2021

Comparing Machine Learning Techniques With State-Of-The-Art Parametric Prediction Models For Predicting Soybean Traits, Susweta Ray

Department of Statistics: Dissertations, Theses, and Student Work

Soybean is a significant source of protein and oil, and also widely used as animal feed. Thus, developing lines that are superior in terms of yield, protein and oil content is important to feed the ever-growing population. As opposed to the high-cost phenotyping, genotyping is both cost and time efficient for breeders while evaluating new lines in different environments (location-year combinations) can be costly. Several Genomic prediction (GP) methods have been developed to use the marker and environment data effectively to predict the yield or other relevant phenotypic traits of crops. Our study compares a conventional GP method (GBLUP), a …


Soil Health Monitoring And Management In Corn And Soybean Agroecosystems Of The Midwestern U.S., Bradley S. Crookston Dec 2021

Soil Health Monitoring And Management In Corn And Soybean Agroecosystems Of The Midwestern U.S., Bradley S. Crookston

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Soil health is a concept and condition of the soil where measurable soil properties represent the capacity of a soil fulfilling its intended use, such as producing crops, without constraint to its agro-ecological quality. Soil health assessments are used to estimate the health of a soil by assessing soil biological, chemical, and physical attributes, called soil health indicators, and scoring them on a scale, usually 0 to 100, to guide soil and crop management. However, there are few large-scale analyses of soil health assessment scores and their relationships with crop yield. Understanding how soil health assessments relate to crop yield …


Nutrient Uptake And Management Strategies In Recirculating Hydroponic Systems, Lauren Leigh Houston Dec 2021

Nutrient Uptake And Management Strategies In Recirculating Hydroponic Systems, Lauren Leigh Houston

Graduate Theses and Dissertations

Nutrient management in recirculating hydroponic systems requires the periodic replenishment of water and nutrients to the nutrient solution reservoir. Common nutrient management strategies, such as replenishing the reservoir with fresh solution and maintaining a constant solution electrical conductivity (EC), can lead to ion accumulation and nutrient imbalances since nutrients are taken up by roots and depleted from solution at different rates. To avoid nutritional disorders, commercial growers typically dump and replace the hydroponic solution periodically, which is wasteful and has an economic cost. A potential alternative is to specially formulate the nutrient replenishment solution to balance the supply of nutrients …


Crispr Gene Editing Drivers, Barriers And Prospects: A Comparative Study Among Plant Scientists Globally, Adriaan Johannes De Lange Dec 2021

Crispr Gene Editing Drivers, Barriers And Prospects: A Comparative Study Among Plant Scientists Globally, Adriaan Johannes De Lange

Graduate Theses and Dissertations

The introduction of CRISPR gene editing into food crops has potential to contribute to food security and sustainable food production globally. To date, most scientific studies have focused on consumer perception of CRISPR gene edited foods or the potential benefits and risks of the CRISPR technology and none have focused on the perceptions of plant scientists concerning CRISPR gene editing. This study aimed to explore the investments, functions, barriers, benefits for specific crops and beneficiaries of CRISPR gene editing according to plant scientists, by distributing an online survey in which 1,040 plant scientists active across six continents and in both …


Economic Potash Fertilizer Rate Recommendations, Kimberly B. Oliver Dec 2021

Economic Potash Fertilizer Rate Recommendations, Kimberly B. Oliver

Graduate Theses and Dissertations

This thesis is comprised of two studies that estimate profit-maximizing potassium (K) fertilizer application rates for various crops across different time periods. Estimation of profit-maximizing fertilizer-K rate (K*) for both studies considered the initial soil test level of K (STK) and yield response information, as traditional recommendations do, and added crop price and the cost of fertilizer. Profit maximum occurs where the marginal revenue from additional yield is equal to the marginal cost of applying an additional unit of fertilizer-K. The first study calculated K* for corn (Zea mays) and cotton (Gossypium hirsutum) and compared results to previous studies on …


Recapture And Reuse Of Nitrogen And Phosphorus From Rendered Animal Materials To Enhance Nutrient Use Efficiency And Produce Quality In Agricultural Crop, Bhupinder Jatana Dec 2021

Recapture And Reuse Of Nitrogen And Phosphorus From Rendered Animal Materials To Enhance Nutrient Use Efficiency And Produce Quality In Agricultural Crop, Bhupinder Jatana

All Dissertations

The current fertilizer regime heavily relies on inorganic fertilizers to meet the crop nitrogen (N) and phosphorus (P) demand. However, the United States has a limited N production capacity, with 50% N demand met through imports. On the other hand, the nonrenewable natural reserves of P are being depleted at an unprecedented rate and are expected to be exhausted with in next 100 years. Additionally, high solubility/liability of the field applied inorganic fertilizers often results in lower nutrient use efficiency (NUE;

The MBM led to rapid N mineralization, with 35% of the applied N mineralized within the first five days …


Integrated Weed Management Strategies For Palmer Amaranth (Amaranthus Palmeri) In Cotton And Soybean Production Systems, Rodger Bruce Farr Dec 2021

Integrated Weed Management Strategies For Palmer Amaranth (Amaranthus Palmeri) In Cotton And Soybean Production Systems, Rodger Bruce Farr

Graduate Theses and Dissertations

Management of Palmer amaranth [Amaranthus palmeri (S.) Wats.] in the Midsouth in soybean [Glycine max (L.)] and cotton (Gossypium hirsutum L.) production systems has become increasingly troublesome due to resistance to many of the commonly utilized herbicides in these systems. Developments have been made to utilize new chemistries as well as incorporate integrated weed management strategies to control Palmer amaranth, but questions have risen given the economic feasibility or effectiveness of these new strategies. Additionally, regulation has limited producers’ abilities to utilize some herbicide chemistries. As a result, experiments were conducted to 1) understand the utility of isoxaflutole in isoxaflutole-tolerant …


Measuring Ecosystem Services From Soil Health. Vermont Payment For Ecosystem Services Technical Research Report #1, Alissa C. White, Heather M. Darby, Benjamin Timothy Dube, Bryony Sands, Joshua W. Faulkner, Meredith Albers, Maggie Payne Dec 2021

Measuring Ecosystem Services From Soil Health. Vermont Payment For Ecosystem Services Technical Research Report #1, Alissa C. White, Heather M. Darby, Benjamin Timothy Dube, Bryony Sands, Joshua W. Faulkner, Meredith Albers, Maggie Payne

UVM Extension Faculty Publications

There are a multitude of approaches to evaluating soil health and the soil processes influenced by soil health. As the state of Vermont explores innovative programs that compensate farmers for soil health and associated ecosystem services, the selection of soil health indicators and quantification methods is a foundational first step that influences other aspects of program design. What is measured determines the ecosystem services that can be inferred, the accuracy of data that informs decisions, and programmatic transaction costs. Simply put, what is measured matters. The PES Working Group identified organic matter, bulk density, aggregate stability, greenhouse gas flux from …


Assessing Freezing Effect On Kiwifruit Cultivars And Mapping Suitable Areas For Growing The Crop In Eastern Texas, Lais De Oliveira Machado Dec 2021

Assessing Freezing Effect On Kiwifruit Cultivars And Mapping Suitable Areas For Growing The Crop In Eastern Texas, Lais De Oliveira Machado

Electronic Theses and Dissertations

Kiwifruit is a perennial vine originating from China where it has been grown for centuries. In the United States, green kiwifruit (Actinidia deliciosa) is primarily produced commercially in California. They are fuzzy, green fleshed and well known in the marketplace. Kiwifruit plants require low to moderate soil pH, adequate winter chilling and adequate precipitation to guarantee plant development and good fructification. Actinidia chinesis or golden kiwifruit are smooth skinned, feature golden flesh and are a more recent introduction into the global market. Kiwifruit crops have attributes that favor production in east Texas, including low pest problems, current long …


Cover Crop Effects On Near-Surface Soil Aggregate Stability In The Southern Mississippi Valley Loess (Mlra 134), Chandler M. Arel Dec 2021

Cover Crop Effects On Near-Surface Soil Aggregate Stability In The Southern Mississippi Valley Loess (Mlra 134), Chandler M. Arel

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Intensive agricultural cultivation within major land resource area (MLRA) 134, the Southern Mississippi Valley Loess, has led to soil erosion, soil compaction, and the overall destabilization of near-surface soil aggregates. The use of cover crops during the agricultural offseason has been shown to help alleviate soil compaction and provide stabilizing effects against soil erosion, which are particularly important as the silty soils of MLRA 134 have a large erosion potential. This study evaluated the effects of cover crop and no-cover crop treatment on silt-loam soils within MLRA 134. Treatments were implemented during Fall 2018 and Fall 2019 and consisted of …


Comparing Organic And Conventional Yield Responses To Climate Variations, Joost Wilken Meyer Dec 2021

Comparing Organic And Conventional Yield Responses To Climate Variations, Joost Wilken Meyer

Graduate Theses and Dissertations

This thesis compares the responses of organic yields and conventional yields towards climate variations. To achieve this objective, weather variables such as growing season weather conditions (average temperature, precipitation, cloud cover, relative humidity, drought index), weather anomalies, the occurrence of severe or extreme droughts and excessive rainfalls, are combined with 23 data sets gathered from previous studies that compare organic and conventional yields from the same location and time periods. To narrow the scope, the thesis focuses on soybean, maize, and wheat production in Europe and North America. Study-level fixed-effects models are used to control for any time-invariant factors such …


Sensitivity Of Soybean And Rice To Dicamba, Owen Wesley France Dec 2021

Sensitivity Of Soybean And Rice To Dicamba, Owen Wesley France

Graduate Theses and Dissertations

Although the integration of dicamba as a postemergence (POST) herbicide has proven useful in controlling many herbicide-resistant weeds, its damage to soybean at low rates, such as supplied by drift and volatility, has been well-documented. Injury to other crops, such as rice, from off-target movement of dicamba and other commonly used herbicides, such as glyphosate, may also occur. Practical options for mitigating injury and yield loss to soybean and other crops from dicamba off-target movement could prove beneficial if dicamba continues to be used during summer months. Experiments were conducted to determine the effects of multiple agricultural practices, including cultivar …


Field Evaluation Of Struvite As A Phosphorus Source, Niyi Sunday Omidire Dec 2021

Field Evaluation Of Struvite As A Phosphorus Source, Niyi Sunday Omidire

Graduate Theses and Dissertations

Phosphorus (P) is an element that is crucial in many biological processes in all forms of life and is not substitutable. Excess P in wastewaters leading to the degradation of receiving waters or eutrophication once released is a major environmental concern. Removal of excess P from wastewater as the mineral struvite (MgNH4PO4·6H2O) could be a promising solution to reduce P discharge into receiving waters and can potentially provide a valuable fertilizer-P source for agricultural production. The objectives of this project were to evaluate the effects of: 1) chemically precipitated struvite (CPST), compared to triple superphosphate (TSP) and an unamended control …


The Medium-Term Impacts Of Integrated Crop–Livestock Systems On Crop Yield And Economic Performance, Teerath Singh Rai, Thandiwe Nleya, Sandeep Kumar, Peter Saxton, Tong Wang, Yubing Fan Dec 2021

The Medium-Term Impacts Of Integrated Crop–Livestock Systems On Crop Yield And Economic Performance, Teerath Singh Rai, Thandiwe Nleya, Sandeep Kumar, Peter Saxton, Tong Wang, Yubing Fan

Agronomy, Horticulture and Plant Science Faculty Publications

Integrated crop–livestock (ICL) systems are diverse production systems that can improve resource utilization through spatially or temporally rotating land among crop, livestock, and pasture uses. However, research on whether the enhanced resource utilization translates to greater crop productivity is still warranted. A field experiment was initiated at South Dakota State University in 2016 to determine the impacts of integrating cover crops and livestock grazing into a crop rotation of oat (Avena sativa L.)–maize (Zea mays L.)–soybean [Glycine max (L.) Merr.]. The objectives were to (a) determine the medium-term (4–6 yr) impacts of cover crops and livestock grazing …


Cover Crops To Improve Soil Health In The North American Great Plains, Augustine K. Obour, Logan M. Simon, Jonathon D. Holman, Patrick M. Carr, Meagan Schipanski, Steven Fonte, Rajan Ghimire, Thandiwe Nleya, Humberto Blanco-Canqui Dec 2021

Cover Crops To Improve Soil Health In The North American Great Plains, Augustine K. Obour, Logan M. Simon, Jonathon D. Holman, Patrick M. Carr, Meagan Schipanski, Steven Fonte, Rajan Ghimire, Thandiwe Nleya, Humberto Blanco-Canqui

Agronomy, Horticulture and Plant Science Faculty Publications

Rotating cereal crops (e.g., wheat [Triticum aestivum L.] with a 10- to 21-mo summer fallow period [fallow]) is a common farming practice in dryland (rainfed) agricultural regions. Fallow is associated with several challenges including low precipitation storage efficiency, depletion of soil organic carbon (SOC), loss of soil fertility, little crop residue retention and soil erosion, and few control options for herbicide-resistant (HR) weeds. The inability to effectively control HR weeds poses a major challenge to maintaining soil and water conservation practices such as no-tillage, as some producers are considering tillage to control weeds. Cover crop (CC) integration into wheat-based …