Open Access. Powered by Scholars. Published by Universities.®

Agronomy and Crop Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 12 of 12

Full-Text Articles in Agronomy and Crop Sciences

Evaluating Mine Soil Prepared By Scraper Pans For Herbaceous Plants And Pine Seedlings At An East Texas Lignite Surface Mine, Hannah Z. Angel Aug 2017

Evaluating Mine Soil Prepared By Scraper Pans For Herbaceous Plants And Pine Seedlings At An East Texas Lignite Surface Mine, Hannah Z. Angel

Electronic Theses and Dissertations

Since 1974, Luminant Mining Company, LLC (Luminant) has planted over 38.7 million trees on its reclaimed lignite surface mine operations in Texas. For decades, the use of improved reclamation techniques on Luminant’s mined lands have resulted in over 31,160 ha reclaimed to forests, wildlife habitat, and pastures with productivity levels similar to those found on unmined lands. The development of new reclamation methodologies offers opportunities to further improve productivity of planted trees at Luminant’s Martin Lake Oak Hill Mine in east Texas. The conventional haulback or ‘truck shovel’ reclamation method uses haul trucks for the selective transport and placement of …


Pinching And Spacing Effects On Cut Sunflower (Helianthus Annuus) Production In East Texas, Rebecca B. Burnett Aug 2017

Pinching And Spacing Effects On Cut Sunflower (Helianthus Annuus) Production In East Texas, Rebecca B. Burnett

Electronic Theses and Dissertations

Three experiments evaluated pinching and spacing on Helianthus annuus in East Texas to determine their effects on growth and development. Experiment 1 was designed to determine the effects of pinching nodes 1, 2, 3, or 4 on ‘Pro Cut Gold’ sunflowers. Results from experiment 1 showed non-pinched plants produced marketable stem lengths and flower sizes, while pinched plants’ stem length, stem diameter, flower diameter, and disk diameter decreased compared to the non-pinched plants. The objective for experiment 2 was to evaluate pinching and spacing treatments on ‘Pro Cut Gold’ sunflowers. All spacings for non-pinched plants in experiment 2 produced marketable …


Phytophthora Sojae Infecting Soybean: Pathotype Diversity, New Sources Of Resistance And Interaction With The Soybean Cyst Nematode, Rawnaq Nazneen Chowdhury Jan 2017

Phytophthora Sojae Infecting Soybean: Pathotype Diversity, New Sources Of Resistance And Interaction With The Soybean Cyst Nematode, Rawnaq Nazneen Chowdhury

Electronic Theses and Dissertations

Phytophthora root and stem rot, caused by Phytophthora sojae Kaufmann and Gerdemann, is an important disease of soybean (Glycine max L.) in South Dakota. To gain a better understanding of the importance of P. sojae in South Dakota, specifically pathotype diversity, identification of new resistance sources and the interaction with the soybean cyst nematode (Heterodera glycines Ichinohe, SCN), this research was undertaken with the following objectives - 1) to characterize the pathotype diversity of P. sojae causing Phytophthora root and stem rot on soybean in commercial fields in South Dakota; 2) to compare inoculation methods to evaluate for …


Interactive Effects Of Cover Crops, Invertebrate Communities And Soil Health In Corn Production Systems, Claire Lacanne Jan 2017

Interactive Effects Of Cover Crops, Invertebrate Communities And Soil Health In Corn Production Systems, Claire Lacanne

Electronic Theses and Dissertations

The adoption of regenerative farming practices is gaining traction, but the costs and benefits are not often considered on a systems level. Encouraging biodiversity and soil health is the goal of many agricultural practices used in regenerative farming; regenerative systems employ practices which abide by the two main principles of increasing biodiversity and decreasing disturbance, with the goal of encouraging ecosystem functioning to minimize inputs and maximize the productivity of a farm. I examined the management of corn (Zea mays) fields across four states in the Upper Midwest region of the United States. Regenerative systems in this study …


Using Gluten Index To Improve Spring Wheat Loaf Volume Prediction, Yaming Lu Jan 2017

Using Gluten Index To Improve Spring Wheat Loaf Volume Prediction, Yaming Lu

Electronic Theses and Dissertations

Wheat (Triticum aestivum L.) is the most widely cultivated crop in the world and contributes about 20% of the total dietary calories and proteins globally. Unique properties of doughs formed from wheat flour make it feasible to produce a range of food, including bread. Loaf volume is the most perceptible indicator for breadmaking quality. Selection in the early generations for loaf volume is difficult due to the requirement of the large volume of grains and due to the costly, time-consuming, and labor-intensive evaluation process. Identification of simple and reliable predictive tests for loaf volume is highly desirable. This study …


Soil Response To Cropping Sequences And Grazing Under Integrated Crop-Livestock System, Hanxiao Feng Jan 2017

Soil Response To Cropping Sequences And Grazing Under Integrated Crop-Livestock System, Hanxiao Feng

Electronic Theses and Dissertations

Integrated crop-livestock system (ICLS) is helpful in diversifying a farm for improving its long-term sustainability and economic benefits. In the United States, the ICLS has been increasing in recent years because of its economic and environmental benefits. However, the impacts of ICLS on soil quality is not well documented in North Dakota. The objective of our study is to assess the impacts of cropping sequences and cattle grazing on the selected soil properties in the crop diversity and livestock integration practice. This study site was established in 2010 at the Dickinson Research Extension Center, Dickinson, North Dakota. The study design …


Development Of Best Management Practices For Production Of Ethiopian Mustard (Brassica Carinata) In South Dakota, Phillip Kenneth Alberti Jan 2017

Development Of Best Management Practices For Production Of Ethiopian Mustard (Brassica Carinata) In South Dakota, Phillip Kenneth Alberti

Electronic Theses and Dissertations

Ethiopian mustard (Brassica carinata) is an alternative non-food oilseed crop which has received interest for its potential as a low-input option for production in the Northern Great Plains (NGP). As B. carinata is a new crop to the NGP, the best management practices have yet to be developed. The overall goal of this project was to develop best management practices for B. carinata production in two diverse agroenvironments in South Dakota. Two field experiments were conducted to assess the response of two B. carinata varieties to i) four seeding rates (4.5, 9, 13.5, and 18 kg ha-1 …


Molecular Characterization Of Spot Blotch And Bacterial Leaf Streak Resistance In Bread Wheat, Girma Ayana Jan 2017

Molecular Characterization Of Spot Blotch And Bacterial Leaf Streak Resistance In Bread Wheat, Girma Ayana

Electronic Theses and Dissertations

Spot blotch (SB), caused by Bipolaris sorokiniana (Sacc.) Shoem, and bacterial leaf streak (BLS), caused by Xanthomonas translucens pv. undulosa (Smith et al.), two important foliar diseases of wheat in the major production regions of the US and the world. Deployment of adequate host resistance against them depends on determining the resistance genes or quantitative trait loci (QTLs) responsible for the trait and identification of genetic markers linked to QTL that facilitate markers assisted breeding. We conducted two independent studies and characterized QTLs for BLS and SB resistance. In the first study, we constructed a genetic linkage map of 1,211 …


Mitigating Risks Of Ochratoxin A Contamination In Oats, Bandana Dhungana Jan 2017

Mitigating Risks Of Ochratoxin A Contamination In Oats, Bandana Dhungana

Electronic Theses and Dissertations

Ochratoxin A (OTA) is a toxic metabolite produced by several species of fungal genera Penicillium and Aspergillus. The major OTA producer in temperate regions (i.e. U.S., Canada, Europe) is Penicillium verrucosum. Oat (Avena sativa), like any other cereal grain, can be contaminated with OTA when storage conditions are favorable for fungal growth. The presence of OTA exceeding the European Union maximum limit of 3 ppb in processed food has been reported in some samples of oat-based breakfast cereals from the US. The use of oat genotypes with limited OTA accumulation would be an effective way to …


Characterization Of Pyrenophora Tritici-Repentis In Wheat And Rye To Study Tan Spot Susceptibility And Insights Into Its Relationship With Stem Rust Resistance, Sidrat Abdullah Jan 2017

Characterization Of Pyrenophora Tritici-Repentis In Wheat And Rye To Study Tan Spot Susceptibility And Insights Into Its Relationship With Stem Rust Resistance, Sidrat Abdullah

Electronic Theses and Dissertations

Tan spot, caused by the ascomycete fungus, Pyrenophora tritici-repentis (Ptr), is a major foliar fungal disease of wheat worldwide. To date, Ptr isolates have been grouped into eight races based on the production of three host selective effectors (toxins), Ptr ToxA, ToxB, and ToxC, which are associated with necrosis and chlorosis symptoms on wheat differential lines. In order to see the correlation between stem rust resistance and tan spot susceptibility in 1970’s, to know the pathogen virulence profile, and explore the sources of tan spot resistance, we recovered isolates from wheat and rye and evaluated wheat and rye lines with …


Terracing, Land Management And Agricultural Soils In The Andagua Valley Of The Southern Peruvian Andes, Blaise Murphy Jan 2017

Terracing, Land Management And Agricultural Soils In The Andagua Valley Of The Southern Peruvian Andes, Blaise Murphy

Electronic Theses and Dissertations

Demographic, socio-political and climatic changes can drastically alter agricultural land management practices, affecting the availability of agriculturally relevant nutrients in the soil. This project investigates the use, reconstruction and abandonment of agricultural terraces and the implications these conditions have on agricultural soil properties of the Andagua Valley in the Western Cordillera of the Southern Peruvian Andes. During the 2016 summer field season, topsoil samples were collected from cultivated and abandoned agricultural terraces between 3229m and 3688m a. s. l. with a range of aspects and ages. Collaboration with a team of archaeologists and anthropologists gave insight into the local and …


Effects Of Fertilizer And Shade Management On Nitrogen Mineralization, Nitrifying Microbial Abundance And Nitrogen-Fixing Capacity Of Erythrina Poeppigiana In Coffee (Coffea Arabica) Agroforestry Systems In Costa Rica, Stuart E. Barker Iii Jan 2017

Effects Of Fertilizer And Shade Management On Nitrogen Mineralization, Nitrifying Microbial Abundance And Nitrogen-Fixing Capacity Of Erythrina Poeppigiana In Coffee (Coffea Arabica) Agroforestry Systems In Costa Rica, Stuart E. Barker Iii

Electronic Theses and Dissertations

Worldwide chemical fertilizer use has increased by four times during the last 50 years. Conventional agricultural systems have a high nitrifying nature, resulting in a loss of nearly 70% of overall nitrogen (N) fertilizer inputs, an estimated economic loss of $81 billion. Over application of fertilizer is rampant in tropical developing nations in Central America, where coffee is major crop. Agroforestry offers ecologically sustainable land management strategies that promote the provision of ecosystem services such as, protection of biodiversity, climate change mitigation, and water and soil regulation. When legume trees are incorporated as the shade tree in coffee production, direct …