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Agronomy and Crop Sciences

Purdue University

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Articles 1 - 30 of 53

Full-Text Articles in Plant Sciences

Modelling The "Bottom-Up" Development Pattern Of Tar Spot Disease In Corn, Brenden Lane, Joaquín Guillermo Ramírez-Gil, Carlos Góngora-Canul, Mariela Sofia Fernandez Campos, Andres Cruz-Sancan, Fidel E. Jiménez-Beitia, Alex G. Acosta-Guatemal, Wily Sic, C. D. Cruz Mar 2024

Modelling The "Bottom-Up" Development Pattern Of Tar Spot Disease In Corn, Brenden Lane, Joaquín Guillermo Ramírez-Gil, Carlos Góngora-Canul, Mariela Sofia Fernandez Campos, Andres Cruz-Sancan, Fidel E. Jiménez-Beitia, Alex G. Acosta-Guatemal, Wily Sic, C. D. Cruz

Graduate Industrial Research Symposium

In 2015, the corn-infecting pathogen Phyllachora maydis (causal agent of tar spot disease) was reported for the first time in the United States. The disease has since spread across the US, causing major yield losses. In 2021 alone, 5.88 million metric tons (231.3 million bushels) of US corn yield were lost to this disease, costing an estimated US$1.25 billion. Though fungicides can protect against these agroeconomic losses, application timing can be difficult to optimize because our understanding of tar spot dynamics is still evolving. The current view is that tar spot typically develops bottom-up through a repeating infection cycle. Because …


Co-Crystallization Of Urea Granules For Slower Dissolution, Vidya Nagaraju, Carl Wassgren, Kingsly Ambrose Mar 2024

Co-Crystallization Of Urea Granules For Slower Dissolution, Vidya Nagaraju, Carl Wassgren, Kingsly Ambrose

Graduate Industrial Research Symposium

Co-crystals are multicomponent crystals formed through hydrogen bond interactions. Co-crystallization, the process of developing cocrystals, serves as a versatile approach for discovering new solid forms of active ingredients (AIs) that can alter physical properties such as solubility, dissolution rates, and stability. These co-crystals can be produced through three main methods: solid-state methods, solution-based methods, and supercritical fluid methods. Recently, the solid-state (mechanochemical) method of developing cocrystals has gained more attention from researchers in the development of slow-release urea fertilizers. This technique can also be applied to the development of urease inhibitors. These multicomponent crystals present a potential solution to the …


The Impact Of Soil On Climate Change And Human Health, Alec S. Patterson Jan 2022

The Impact Of Soil On Climate Change And Human Health, Alec S. Patterson

Ideas: Exhibit Catalog for the Honors College Visiting Scholars Series

As we continue to see the effects of climate change on our world, we are forced to question everything about our lives. One of the most heavily impacted industries due to climate change is the food industry, which is tasked with finding sustainable ways to produce food in any circumstances. This paper establishes what makes a healthy soil, how soil health affects the crops it grows, and the effects these crops have on human health when consumed. Finally, farming techniques, which may help improve the health of our soil are explored.


Internet Of Things In Agricultural Innovation And Security, Abdul Salam Jan 2020

Internet Of Things In Agricultural Innovation And Security, Abdul Salam

Faculty Publications

The agricultural Internet of Things (Ag-IoT) paradigm has tremendous potential in transparent integration of underground soil sensing, farm machinery, and sensor-guided irrigation systems with the complex social network of growers, agronomists, crop consultants, and advisors. The aim of the IoT in agricultural innovation and security chapter is to present agricultural IoT research and paradigm to promote sustainable production of safe, healthy, and profitable crop and animal agricultural products. This chapter covers the IoT platform to test optimized management strategies, engage farmer and industry groups, and investigate new and traditional technology drivers that will enhance resilience of the farmers to the …


Internet Of Things For Sustainable Forestry, Abdul Salam Jan 2020

Internet Of Things For Sustainable Forestry, Abdul Salam

Faculty Publications

Forests and grasslands play an important role in water and air purification, prevention of the soil erosion, and in provision of habitat to wildlife. Internet of Things has a tremendous potential to play a vital role in the forest ecosystem management and stability. The conservation of species and habitats, timber production, prevention of forest soil degradation, forest fire prediction, mitigation, and control can be attained through forest management using Internet of Things. The use and adoption of IoT in forest ecosystem management is challenging due to many factors. Vast geographical areas and limited resources in terms of budget and equipment …


Impact Of Pesticide Regulation On Innovation In The United States And European Union, Brooke D. Schafer Aug 2019

Impact Of Pesticide Regulation On Innovation In The United States And European Union, Brooke D. Schafer

The Journal of Purdue Undergraduate Research

No abstract provided.


A Theoretical Model Of Underground Dipole Antennas For Communications In Internet Of Underground Things, Abdul Salam, Mehmet C. Vuran, Xin Dong, Christos Argyropoulos, Suat Irmak Feb 2019

A Theoretical Model Of Underground Dipole Antennas For Communications In Internet Of Underground Things, Abdul Salam, Mehmet C. Vuran, Xin Dong, Christos Argyropoulos, Suat Irmak

Faculty Publications

The realization of Internet of Underground Things (IOUT) relies on the establishment of reliable communication links, where the antenna becomes a major design component due to the significant impacts of soil. In this paper, a theoretical model is developed to capture the impacts of change of soil moisture on the return loss, resonant frequency, and bandwidth of a buried dipole antenna. Experiments are conducted in silty clay loam, sandy, and silt loam soil, to characterize the effects of soil, in an indoor testbed and field testbeds. It is shown that at subsurface burial depths (0.1-0.4m), change in soil moisture impacts …


Expression Of Carbohydrates Biosynthetic Genes In Developing Soybean Seeds, Jayden Rosen, Karen A. Hudson Aug 2018

Expression Of Carbohydrates Biosynthetic Genes In Developing Soybean Seeds, Jayden Rosen, Karen A. Hudson

The Summer Undergraduate Research Fellowship (SURF) Symposium

An essential part of livestock diets is soybean meal, which is a major source of protein, but which also consists of antinutritional carbohydrates. Antinutritional carbohydrates such as raffinose and stachyose lead to irritation to the gut for monogastric livestock as well as unhealthy weight gain. A major objective of soybean genetics is to reduce these antinutritional carbohydrates within the seed and increase the levels of good carbohydrates. This will lead to healthier livestock and better meat quality. To select genes potentially responsible for variation in carbohydrate levels in seeds, the expression of genes encoding several biosynthetic enzymes was measured during …


Impact Of Automated Guidance For Mechanical Control Of Herbicide-Resistant Weeds In Corn, Terry Griffin, James M. Lowenberg-Deboer Oct 2017

Impact Of Automated Guidance For Mechanical Control Of Herbicide-Resistant Weeds In Corn, Terry Griffin, James M. Lowenberg-Deboer

Journal of Applied Farm Economics

This study evaluated the feasibility of reintroducing mechanical weed control as an alternative for herbicide-resistance weed infestations. The production practice tested included row cultivation with a separate banded spray application using high-accuracy automated guidance systems. A range of ground speeds were tested for the row cultivation operation, each with a different per acre cost and timeliness penalty. A typical eastern Corn Belt farm with a rotation of corn and soybean served as the base for the linear programming model. It was found that if the farmer was willing to reintroduce tillage, row cultivation conducted at higher operating speeds in conjunction …


Annual Forage Cropping-Systems For Midwestern Ruminant Livestock Production, John Ernest Mcmillan Dec 2016

Annual Forage Cropping-Systems For Midwestern Ruminant Livestock Production, John Ernest Mcmillan

Open Access Dissertations

Annual forage cropping systems are a vital aspect of livestock forage production. One area where this production system can be enhanced is the integration of novel annual forages into conventional cropping systems. Two separate projects were conducted to investigate alternative forage options in annual forage production. In the first discussed research trial, two sets of crops were sown following soft red winter wheat (Triticum aestivum L.) grain harvest, at two nitrogen application rates 56 and 112 kg ha-1 . The first set of crops were C4 summer annuals seeded within two weeks of wheat grain harvest and included, brown …


Evaluation Of A Cool-Season Grass-White Clover Mixture For Low-Nitrogen Input Lawns, Gabriel Adam Macke Dec 2016

Evaluation Of A Cool-Season Grass-White Clover Mixture For Low-Nitrogen Input Lawns, Gabriel Adam Macke

Open Access Theses

Turfgrass lawns require supplemental nitrogen (N) to maintain green color and seasonal shoot density. Improper lawn fertilization with excess N or phosphorus has the potential to contaminate both surface and groundwater. Thus, to reduce the reliance on supplemental N fertilization, alternative strategies or novel turf systems like grass-legume mixtures need explored. White clover ( Trifolium repens L.) is a stoloniferous legume that biologically fixes N from the atmosphere and adds N into the soil via mineralization. The objective of this field study was to evaluate the persistence and feasibility of a cool-season grass-clover lawn mixture. A lawn grass mixture with …


Residual Effects Of Nitrogen Fertilization On Soil Nitrogen Pools And Corn Growth, Meghan E. Moser Dec 2016

Residual Effects Of Nitrogen Fertilization On Soil Nitrogen Pools And Corn Growth, Meghan E. Moser

Open Access Theses

Given the dynamic nature of soil nitrogen (N), inorganic N fertilization to corn (Zea mays L.) has potential to alter N pool balance by creating an accumulation or depletion of soil N. Current corn N recommendations in the common corn-soybean rotation of Indiana strive to find the best N rate that maximizes producer profit. Increasing our understanding of soil N will inform producers if they should adjust fertilizer rates for corn to influence maintenance of organic N and Carbon. Our objective was to determine residual N effects from fertilized corn in a corn-soybean rotation by measuring (1) soil N …


Cereal Rye Cover Crop Effects On Soil Physical And Chemical Properties In Southeastern Indiana, Joseph D. Rorick Dec 2016

Cereal Rye Cover Crop Effects On Soil Physical And Chemical Properties In Southeastern Indiana, Joseph D. Rorick

Open Access Theses

Cover crops are growing in popularity in the Midwest, although questions remain about how to include them most effectively in a corn-soybean ( Zea mays L. - Glycine max L.) rotation. This study was conducted to determine the effects of cereal rye ( Secale cereale L.) on soil bulk density and water retention, soil organic carbon, soil nitrogen, and water stable aggregate mean weight diameter after four years of cover crop growth and the effects on soil moisture over a five year period. The study was conducted at the Southeast Purdue Agricultural Center (SEPAC) on silt loam soils. A 14 …


Physiological Aspects Of Relative Changes In Nitrogen And Plant Density Stress Tolerances Over A 38-Year Period Of Us Maize Hybrid Introductions, Keru Chen Dec 2016

Physiological Aspects Of Relative Changes In Nitrogen And Plant Density Stress Tolerances Over A 38-Year Period Of Us Maize Hybrid Introductions, Keru Chen

Open Access Dissertations

Incremental gains in grain yield of maize hybrids over the decades are the consequence of genotype, environment and management interactions. Historically, genetic improvements in newer hybrids have included longer active grain filling periods (achieved by advancing silking and extending functional stay green in maize leaves); stronger source and sink during grain filling; enhanced tolerance to higher density; and canopy architecture changes. Newer hybrids were known to accumulate more dry matter and nitrogen in the post-silking period, but achieving a more comprehensive knowledge of pre-silking and post-silking dynamics required further understanding of dry matter and nitrogen partitioning in individual organs, as …


The Biology And Management Of Palmer Amaranth (Amaranthus Palmeri S. Wats) In Indiana, Douglas J. Spaunhorst Dec 2016

The Biology And Management Of Palmer Amaranth (Amaranthus Palmeri S. Wats) In Indiana, Douglas J. Spaunhorst

Open Access Dissertations

Palmer amaranth is a pernicious summer annual weed that has evolved resistance to six herbicide sites of action in the U.S. and threatens agriculture production. In 2011, Palmer amaranth was identified in flood plains in two southern Indiana counties (Posey and Vanderburgh). Determining if Palmer amaranth can survive and reproduce in northern Indiana may provide insight if this weed will be problematic for northern row crop producers. The objectives of our research were to identify fields containing Palmer amaranth and determine the distribution of herbicide resistance traits in Indiana; determine the influence of tillage frequency and tillage intervals on Palmer …


Genetic Study Of Carotenoids In Maize Grain (Zea Mays L.), Oscar Rafael Espejel Venado Dec 2016

Genetic Study Of Carotenoids In Maize Grain (Zea Mays L.), Oscar Rafael Espejel Venado

Open Access Theses

Pro-Vitamin A (proVA) carotenoids, which are converted into retinol (Vitamin A) in the human body, have been the subject of human nutrition studies and are a target for biofortification of staple crops. Historically, β-carotene has been the principal target for enhancing levels of proVA, yet there is recent interest in enhancing the proVA carotenoid β-cryptoxanthin. Studies have shown that β-cryptoxanthin has excellent bioavailability, and its use in maize may be nearly as effective as β-carotene in providing retinol. The primary aim of this study was to gain a better understanding of the genetic control of levels of β-cryptoxanthin, conversion of …


Increasing Maize Tolerance To Drought And Flood With Seed Coating Treatments, Jacob E. Bennett, Achint Sanghi, R. P. Kingsly Ambrose Aug 2016

Increasing Maize Tolerance To Drought And Flood With Seed Coating Treatments, Jacob E. Bennett, Achint Sanghi, R. P. Kingsly Ambrose

The Summer Undergraduate Research Fellowship (SURF) Symposium

The lack of irrigation in regions prone to drought, and flooding due to high rainfall or lack of drainage affects seed viability and the subsequent germination and crop establishment. Seed treatment in the form of coatings shows promise as an effective method to preserve the viability of corn (Zea mays) seeds in drought and flood conditions. Chemical formulations may help improve the seed corn vigor under these stressed conditions. This study examined the efficacy of β-aminobutyric acid [BABA] and N-isopropylacrylamide [NIPA] in inducing drought resistance, as well as the ability of lanolin and linseed oil to provide flood …


The Biology And Management Of Waterhemp In Indiana, Joseph M. Heneghan Aug 2016

The Biology And Management Of Waterhemp In Indiana, Joseph M. Heneghan

Open Access Theses

Waterhemp is a dioecious weed species indigenous to the Midwestern United states yet it has only recently become problematic in agronomic crop production in Indiana. Waterhemp is a small-seeded broadleaf which has increased in prevalence in conjunction with an increase in conservation tillage practices. Waterhemp germinates and emerges from the top 3 cm of soil and is known to exhibit extended periods of continual emergence, longer than most other summer annual weed species that are typically present in agronomic production settings. As a C4 species, waterhemp then grows rapidly and is capable of producing thousands of seeds, while effectively competing …


Nested Association Mapping Of Stem Rust Resistance In Wheat Using Genotyping By Sequencing, Prabin Bajgain, Matthew N. Rouse, Toi J. Tsilo, Godwin K. Macharia, Sridhar Bhavani, Yue Jin, James A. Anderson Jan 2016

Nested Association Mapping Of Stem Rust Resistance In Wheat Using Genotyping By Sequencing, Prabin Bajgain, Matthew N. Rouse, Toi J. Tsilo, Godwin K. Macharia, Sridhar Bhavani, Yue Jin, James A. Anderson

Department of Agronomy Faculty Publications

We combined the recently developed genotyping by sequencing (GBS) method with joint mapping (also known as nested association mapping) to dissect and understand the genetic architecture controlling stem rust resistance in wheat (Triticum aestivum). Ten stem rust resistant wheat varieties were crossed to the susceptible line LMPG-6 to generate F6 recombinant inbred lines. The recombinant inbred line populations were phenotyped in Kenya, South Africa, and St. Paul, Minnesota, USA. By joint mapping of the 10 populations, we identified 59 minor and medium-effect QTL (explained phenotypic variance range of 1%- 20%) on 20 chromosomes that contributed towards adult plant resistance …


Improved Prediction Of Severe Thunderstorms Over The Indian Monsoon Region Using High-Resolution Soil Moisture And Temperature Initialization, K. K. Osuri, R. Nadimpalli, U. C. Mohanty, F. Chen, M. Rajeevan, Dev Niyogi Jan 2016

Improved Prediction Of Severe Thunderstorms Over The Indian Monsoon Region Using High-Resolution Soil Moisture And Temperature Initialization, K. K. Osuri, R. Nadimpalli, U. C. Mohanty, F. Chen, M. Rajeevan, Dev Niyogi

Department of Earth, Atmospheric, and Planetary Sciences Faculty Publications

The hypothesis that realistic land conditions such as soil moisture/soil temperature (SM/ST) can significantly improve the modeling of mesoscale deep convection is tested over the Indian monsoon region (IMR). A high resolution (3 km foot print) SM/ST dataset prepared from a land data assimilation system, as part of a national monsoon mission project, showed close agreement with observations. Experiments are conducted with (LDAS) and without (CNTL) initialization of SM/ST dataset. Results highlight the significance of realistic land surface conditions on numerical prediction of initiation, movement and timing of severe thunderstorms as compared to that currently being initialized by climatological fields …


Long-Term Tillage System Impacts On Soil Erodibility, Julianne R. Chechanover, Dennis C. Flanagan Aug 2015

Long-Term Tillage System Impacts On Soil Erodibility, Julianne R. Chechanover, Dennis C. Flanagan

The Summer Undergraduate Research Fellowship (SURF) Symposium

Conservation tillage practices, such as no-till agriculture, have the potential of reducing the erodibility of a soil compared to conventional agricultural practices. This research sought to determine whether long-term agricultural practices affect the baseline erodibility properties of a soil. Two soils from Throckmorton-Purdue Agricultural Center in Tippecanoe County, Indiana were used during this experiment. One soil was treated with a long-term conventional tillage (fall chisel, spring disk) system and the other soil was treated with a long-term no-till system. The soils’ interrill erodibility, and rill erodibility and critical hydraulic shear stress were measured under a rainfall simulator using soil boxes …


Genetic, Agronomic And Compositional Characterization Of Brown Midrib Sweet Sorghum Lignocellulosic Biomass For Ethanol Production, Luis A. Rivera Burgos Apr 2015

Genetic, Agronomic And Compositional Characterization Of Brown Midrib Sweet Sorghum Lignocellulosic Biomass For Ethanol Production, Luis A. Rivera Burgos

Open Access Dissertations

Sorghum is a promising bioenergy crop due to its unique phenotypic and genotypic attributes. Quality (low lignin and high stem sugar concentration) and quantity (biomass yield, plant height, plant maturity, etc.) biomass traits are key contributors to ethanol yield and production. In this study, a 236 sorghum recombinant inbred line (RIL) population was subjected to genetic, agronomic and compositional characterization for ethanol yield and production. We found that the sweet mutation enhances biomass quantity traits in the RILs which translates to higher ethanol production and biomass quality which improves ethanol yield. The variance components showed from moderate to high heritability …


Cover Crop And No-Till Effects On Soil Health Properties In Indiana, Sara Alford Apr 2015

Cover Crop And No-Till Effects On Soil Health Properties In Indiana, Sara Alford

Open Access Theses

A growing concern of soil health and long-term sustainability has increased interest in no-till and cover crops in the Midwest. Some of the challenges with no-till in the Midwest can be higher soil moisture and lower soil temperatures at cash crop planting in the spring, planter adjustment issues, and lack of immediate economic benefit. Cover crops also have some of the same issues along with extra cost of seed and termination, mismanagement of cover crops, and lack of knowledge on the benefits and costs. This project was begun in order to quantify the effects of no-till and cover crops on …


Genetic Analysis Of Nitrogen Remobilization And Kernel Compositon In Zea Mays L. And Sorghum Bicolor (L.) Moench, Raymond S Lindsey Apr 2015

Genetic Analysis Of Nitrogen Remobilization And Kernel Compositon In Zea Mays L. And Sorghum Bicolor (L.) Moench, Raymond S Lindsey

Open Access Dissertations

Genetic Analysis of Nitrogen Remobilization and Kernel Composition in Zea Mays L. and Sorghum Bicolor (L.) Moench. Major Professor: Mitchell Tuinstra. Modern maize (Zea mays L.) production relies heavily on nitrogen fertilization for high productivity. Over-application of nitrogen fertilizers in cropping systems can have detrimental economic and environmental effects. For this reason, improving Nitrogen Use Efficiency (NUE) is a major goal of breeders and producers. Nitrogen Utilization Efficiency (NUtE) is one component of NUE, and the most important component under N-limited conditions. In this study we examined the genetic controls of the timing and preferential canopy position of leaf N …


Utilization Of Tall Wheatgrass Translocation Lines To Improve Fusarium Head Blight Resistance In Wheat, Xiangye Xiao Apr 2015

Utilization Of Tall Wheatgrass Translocation Lines To Improve Fusarium Head Blight Resistance In Wheat, Xiangye Xiao

Open Access Dissertations

Fusarium head blight (FHB) and leaf rust (LR) are two major fungal pathogens threatening the wheat crop, consequently identifying resistance genes from various sources is always of importance to wheat breeders. Type II FHB resistance in wheat has been improved by introgressing QTL from landraces and wild species. The present study was undertaken to (1) combine two different type II FHB resistance QTL in the backgrounds of six adapted wheat lines (2) improve the map resolution of Qfhs.pur-7EL.^ In the first objective, the FHB resistance gene Fhb1 originated in a Chinese wheat cultivar and is located on wheat chromosome …


What Do Experienced Water Managers Think Of Water Resources Of Our Nation And Its Management Infrastructure?, Faisal Hossain, Jeffrey R. Arnold, Edward Beighley, Casey M. Brown, Steven J. Burian, Ji Chen, Anindita Mitra, Dev Dutta S Niyogi, Roger A. Pielke, Vincent C. Tidwell, Dave Wegner Jan 2015

What Do Experienced Water Managers Think Of Water Resources Of Our Nation And Its Management Infrastructure?, Faisal Hossain, Jeffrey R. Arnold, Edward Beighley, Casey M. Brown, Steven J. Burian, Ji Chen, Anindita Mitra, Dev Dutta S Niyogi, Roger A. Pielke, Vincent C. Tidwell, Dave Wegner

Department of Earth, Atmospheric, and Planetary Sciences Faculty Publications

This article represents the second report by an ASCE Task Committee "Infrastructure Impacts of Landscape-driven Weather Change" under the ASCE Watershed Management Technical Committee and the ASCE Hydroclimate Technical Committee. Herein, the 'infrastructure impacts" are referred to as infrastructure-sensitive changes in weather and climate patterns (extremes and non-extremes) that are modulated, among other factors, by changes in landscape, land use and land cover change. In this first report, the article argued for explicitly considering the well-established feedbacks triggered by infrastructure systems to the land-atmosphere system via landscape change. In this report by the ASCE Task Committee (TC), we present the …


Combining And Mapping Qtl For Fusarium Head Blight (Fhb) Resistance In Wheat, Jin Sun Oct 2014

Combining And Mapping Qtl For Fusarium Head Blight (Fhb) Resistance In Wheat, Jin Sun

Open Access Dissertations

Fusarium head blight (FHB) has become one of the most damaging wheat diseases in humid and semi-humid regions around the world. Single gene resistance to FHB in wheat provides only partial resistance and also the disease severity is highly influenced by environment. Consequently multiple genes are required for effective resistance. Our hypothesis is that identifying DNA markers for type I resistance will be very beneficial for selection, and combining type I and type II FHB resistance will be more effective than either type alone. The objectives of this project are to 1) combine type I resistance from cultivars Goldfield, INW0412, …


Automatic Extraction Of Plots From Geo-Registered Uas Imagery Of Crop Fields With Complex Planting Schemes, Anthony A. Hearst Oct 2014

Automatic Extraction Of Plots From Geo-Registered Uas Imagery Of Crop Fields With Complex Planting Schemes, Anthony A. Hearst

Open Access Theses

Complex planting schemes are common in experimental crop fields and can make it difficult to extract plots of interest from high-resolution imagery of the fields gathered by Unmanned Aircraft Systems (UAS). This prevents UAS imagery from being applied in High-Throughput Precision Phenotyping and other areas of agricultural research. If the imagery is accurately geo-registered, then it may be possible to extract plots from the imagery based on their map coordinates. To test this approach, a UAS was used to acquire visual imagery of 5 ha of soybean fields containing 6.0 m2 plots in a complex planting scheme. Sixteen artificial targets …


Analyzing The Importance Of Diversifying Beyond Tobacco For Small-Scale Farmers In Malawi, Mphatso Charity Mbulukwa Oct 2014

Analyzing The Importance Of Diversifying Beyond Tobacco For Small-Scale Farmers In Malawi, Mphatso Charity Mbulukwa

Open Access Theses

This thesis analyses potential agricultural alternatives to production and marketing of tobacco in Malawi. I study existing patterns of crop and income diversification and factors that limit crop diversification. I also provide an analysis of the current profitability of different important cash crop alternatives that are commonly grown among smallholder farmers and compare their profitability to that of tobacco.

Following a review and synthesis of available literature on alternatives to tobacco, analysis is presented that relies upon data collected in 2009 from 380 households in Kasungu and Machinga districts of Malawi. Simpsons Index of diversification was used to measure the …


Defining Management Strategies To Maximize Net Soil Carbon And Nitrogen Retention In Turfgrass Systems, Quincy D. Law Oct 2014

Defining Management Strategies To Maximize Net Soil Carbon And Nitrogen Retention In Turfgrass Systems, Quincy D. Law

Open Access Theses

Soil carbon (C) sequestration has been proposed as a method to reduce atmospheric carbon dioxide (CO2 ). Managed turf areas are both a source and a sink for greenhouse gases (GHGs) including CO 2 , methane (CH4 ), and nitrous oxide (N2 O), among others. Management practices, including turfgrass selection and mowing, influence the amount of C and N stored in the soil, as well as the direct and indirect GHG emissions. Thus, the objective of this research was to determine how turfgrass selection (both species and cultivar) and mowing practices (such as frequency and grass clipping management) influence the …