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Improving Nitrogen Use Efficiency And Yield In Louisiana Sugarcane Production Systems, Daniel Ernesto Forestieri

LSU Master's Theses

Proper nitrogen (N) management is essential to optimize crop production. This study was conducted to evaluate different N fertilizer management strategies to improve N use efficiency and yield in sugarcane production in Louisiana. This research was initiated in 2013 at the Sugar Research Station in St. Gabriel, LA and was arranged in a randomized complete block design with four replications consisting of different N rates (0, 45, 90, and 135 kg N ha-1) and sources (urea-46% N, ammonium nitrate [AN]-34% N, and urea-ammonium-nitrate solution [UAN]-32% N dribbled and knifed-in) as treatments. Sensor readings were taken from different N response trials …

Chapter 12 - Terrestrial Insects, Janice M. Glime

Bryophyte Ecology Volume 2: Bryological Interaction

Bryophyte Ecology, Volume 2, Chapter 12 - Terrestrial Insects is coming soon. For the Contents section of this ebook, as well as Volumes 1 through 5, please visit the Bryophyte Ecology Main Page.

Ebook sponsored by Michigan Technological University and the International Association of Bryologists.

A Novel Phytoene Synthase Paralog From Halophytic Salicorniaconfers Salinity Tolerance In Plants, Nazia Rehman, Muhammad Ramzan Khan, Ghulam Muhammad Ali

Turkish Journal of Botany

Salicornia seems to be a suitable euhalophyte for the study of salt stress resilience mechanism and exploitation of salinity-tolerant genes for crop yield improvement. In this study, we cloned a novel SePSY1 gene from an extremely salt-tolerant glycophyte, Salicornia europaea. The sequence analysis revealed that the newly isolated gene is a paralog of PSY, suggesting a gene duplication event in Salicornia. The newly isolated gene encodes a protein of 419 amino acids. The C-terminus containing a Trans-IPPS-H domain with catalytic and binding regions exhibits considerable conservation in various species, while the N-terminus remained divergent. The structural analysis suggested a catalytic …

Evaluating The Utility Of Rbcl In Identifying Nigerian Speciesof The Genus Afzelia Sm. (Fabaceae; Caesalpinioideae), Aramide Oshingboye, George Nodza, Temitope Onuminya, Oluwatoyin Ogundipe

Turkish Journal of Botany

The genus Afzelia Sm. (Fabaceae) represents one of the most useful tree species in tropical Africa. These trees have huge socioeconomic and ecological importance, but are under serious threat from incessant exploitation. This has caused a decline of the species in the wild; several species are now registered as threatened and endangered in the IUCN red list. However, conserving this species for posterity has been hampered by the complexity of morphological characters that exist among Afzelia species. In our study, we evaluated the utility of rbcL as a single barcode region, exploring its performance to accurately identify Nigerian Afzelia species …

Responding To Soil Fungal Communities: A Look At Interactions Between Arbuscular Mycorrhizal Fungi And The Common Yellow Monkeyflower, Mariah Mcintosh

Undergraduate Theses, Professional Papers, and Capstone Artifacts

The obligate fungal mutualists arbuscular mycorrhizal fungi (AMF) colonize the roots approximately 80% of vascular plants, generally thought to provide mineral nutrition, pathogen protection, or drought resistance to plants in exchange for photosynthetic carbon. Because of the ecological and evolutionary significance of these interactions, much work has been done to understand this symbiosis at the community level. However, much remains to be understood about how AMF affect plant fitness on an individual level. In this study, we took advantage of the tractability of the emerging model species Mimulus guttatus, the common yellow monkeyflower, to identify genetic differences in how …

Using Exogenous Hormone Application To Suppress Axillary Shoot Development In Tobacco, W. Jesse Carmack

Theses and Dissertations--Plant and Soil Sciences

The variability in the number of basal axillary shoots (ground suckers) among all tobacco (Nicotiana tabacum L.) varieties, has increased since the hydroponic transplant production system became the standard. The larger root ball of hydroponically produced transplants compared to traditionally produced transplants potentially generates a difference in the ratio of auxin (inhibits axillary shoot formation) to cytokinin (promotes lateral branching), that induces basal axillary shoot development. Starting in 2014, studies were conducted to investigate whether the addition of synthetic auxins or cytokinins to hydroponic transplant production could prevent ground sucker formation. Different tobacco cultivars, with high or low ground sucker …

Changes In Soil Microbial Communities After 10 Years Of Winter Wheat Cultivation Versus Fallow In An Organic-Poor Soil In The Loess Plateau Of China, Hui Tian, Hui Wang, Xiaoli Hui, Zhaohui Wang, Rhae A. Drijber, Jinshan Liu

Department of Agronomy and Horticulture: Faculty Publications

Agricultural management methods, such as cultivation or fallowing, have led to significant changes in soil fertility and hence, crop yield. Such changes may have stemmed from changes in soil microbial communities and associated biogeochemical processes. This phenomenon is particularly true in organic-poor soil in the Loess Plateau of China. In this study, we examined three existing soil management regimes as part of a 10-year field experiment and evaluated their effects on fungal and bacterial community structures by performing high-throughput 454 pyrosequencing. These management regimes were (i) fertilized winter wheat (Triticum aestivum L.) (FW), (ii) continuous …

Comparison Of Organic And Integrated Nutrient Management Strategies For Reducing Soil N2O Emissions, Rebecca F. Graham, Samuel E. Wortman, Cameron M. Pittelkow

Department of Agronomy and Horticulture: Faculty Publications

To prevent nutrient limitations to crop growth, nitrogen is often applied in agricultural systems in the form of organic inputs (e.g., crop residues, manure, compost, etc.) or inorganic fertilizer. Inorganic nitrogen fertilizer has large environmental and economic costs, particularly for low-input smallholder farming systems. The concept of combining organic, inorganic, and biological nutrient sources through Integrated Nutrient Management (INM) is increasingly promoted as a means of improving nutrient use efficiency by matching soil nutrient availability with crop demand. While the majority of previous research on INM has focused on soil quality and yield, potential climate change impacts have rarely been …

Rooting For Food Security In Sub-Saharan Africa, Nicolas Guilpart, Patricio Grassini, Justin Van Wart, Haishun Yang, Martin K. Van Ittersum, Lenny G.J. Van Bussel, Joost Wolf, Lieven Claessens, Johan G.B. Leenaars, Kenneth G. Cassman

Department of Agronomy and Horticulture: Faculty Publications

There is a persistent narrative about the potential of Sub-Saharan Africa (SSA) to be a ‘grain breadbasket’ because of large gaps between current low yields and yield potential with good management, and vast land resources with adequate rainfall. However, rigorous evaluation of the extent to which soils can support high, stable yields has been limited by lack of data on rootable soil depth of sufficient quality and spatial resolution. Here we use location-specific climate data, a robust spatial upscaling approach, and crop simulation to assess sensitivity of rainfed maize yields to root-zone water holding capacity. We find that SSA could …

Lettuce Learn: Student Reflections On Building And Sustaining A Community Donation Garden, Hannah Dankbar, Emily K. Zimmerman, Carrie Chennault, Andrea D. Basche, Jacqueline Ann Nester, Maritza Pierre, Gabrielle Roesch-Mcnally

Department of Agronomy and Horticulture: Faculty Publications

This article emerged from conversations that we and fellow graduate students have had in building a community donation garden. We created the garden with a vision of enacting food justice in our community, but over the past four years we have experienced complexities with our vision. In this article, we share the complexities with which we have wrestled, how we have encouraged thoughtful dialogue among fellow scholars about these shortcomings and the intricate workings of the agrifood system, and the lessons we have learned through these experiences as early-career scholar-activists. This article represents our collective and individual voices as graduate …

Shifts In Microbial Communities In Soil, Rhizosphere And Roots Of Two Major Crop Systems Under Elevated Co2 And O3, Peng Wang, Ellen L. Marsh, Elizabeth A. Ainsworth, Andrew D. B. Leakey, Amy M. Sheflin, Daniel P. Schachtman

Department of Agronomy and Horticulture: Faculty Publications

Rising atmospheric concentrations of CO₂ and O₃ are key features of global environmental change. To investigate changes in the belowground bacterial community composition in response to elevated CO₂ and O₃ (eCO₂ and eO₃) the endosphere, rhizosphere and soil were sampled from soybeans under eCO2 and maize under eO₃. The maize rhizosphere and endosphere α-diversity was higher than soybean, which may be due to a high relative abundance of Rhizobiales. Only the rhizosphere microbiome composition of the soybeans changed in response to eCO₂, associated with an increased abundance of nitrogen …

Science In The Supply Chain: Collaboration Opportunities For Advancing Sustainable Agriculture In The United States, Allison M. Thomson, Stewart Ramsey, Ed Barnes, Bruno Basso, Marlen Eve, Sasha Gennet, Patricio Grassini, Brandon Kliethermes, Marty Matlock, Eileen Mcclellen, Ed Spevak, Clifford S. Snyder, Mark D. Tomer, Chris Van Kessel, Tristram West, Grant Wick

Department of Agronomy and Horticulture: Faculty Publications

Consumers and corporations are increasingly interested in understanding the sustainability of agricultural supply chains and reducing the environmental impacts of food, fiber, feed, and fuel production. This emerging need to quantify environmental impacts from agricultural production creates an opportunity for collaboration with the scientific community. Without such collaboration, sustainability efforts risk failure by adopting unrealistic goals or misguided approaches. This commentary explores the role of science in Field to Market, a nonprofit organization developing a sustainability program for US commodity crops, and highlights opportunities to address emerging science challenges. We evaluate changes over the past 35 years in key environmental …

Editorial: Genomic Approaches For Improvement Of Understudied Grasses, Keenan Amundsen, Gautam Sarath, Teresa Donze-Reiner

Department of Agronomy and Horticulture: Faculty Publications

Grasses are diverse, spanning native prairies to high-yielding grain cropping systems. They are valued for their beauty and useful for soil stabilization, pollution mitigation, biofuel production, nutritional value, and forage quality; grasses encompass the most important grain crops in the world. There are thousands of distinct grass species and many have promiscuous hybridization patterns, blurring species boundaries. Resources for advancing the science and knowledgebase of individual grass species or their unique characteristics varies, often proportional to their perceived value to society. For many grasses, limited genetic information hinders research progress. Presented in this research topic is a brief snapshot of …

High-Throughput Profiling And Analysis Of Plant Responses Over Time To Abiotic Stress, Kira M. Veley, Jeffrey C. Berry, Sarah J. Fentress, Daniel P. Schachtman, Ivan Baxter, Rebecca Bart

Department of Agronomy and Horticulture: Faculty Publications

Sorghum (Sorghum bicolor (L.) Moench) is a rapidly growing, high-biomass crop prized for abiotic stress tolerance. However, measuring genotype-by-environment (G x E) interactions remains a progress bottleneck. We subjected a panel of 30 genetically diverse sorghum genotypes to a spectrum of nitrogen deprivation and measured responses using high-throughput phenotyping technology followed by ionomic profiling. Responses were quantified using shape (16 measurable outputs), color (hue and intensity), and ionome (18 elements). We measured the speed at which specific genotypes respond to environmental conditions, in terms of both biomass and color changes, and identified individual genotypes that perform most favorably. With this …

An Assessment Of How Plant And Mycorrhizal Communities Have Been Affected Along A Mine-Impacted Watershed In The Northwest Territories, Kevin Maccoll

Theses and Dissertations (Comprehensive)

Giant Mine is an inactive gold mine located nine kilometers north of Yellowknife, Northwest Territories. Giant Mine has been the source of arsenic trioxide for the Baker Creek watershed since it opened over 60 years ago. Although arsenic levels in the creek are above the limits considered to be biologically relevant, there is no concrete evidence that plants and mycorrhizae have actually been affected. This study provides an initial assessment of the impacts mining activity at Giant Mine has had on plants and mycorrhizae in the Baker Creek watershed. Nine sites were sampled around Giant Mine: five sites downstream from …

Increasing Renewable Oil Content And Utility, William Richard Serson

Theses and Dissertations--Plant and Soil Sciences

Since the dawn of agriculture man has been genetically modifying crop plants to increase yield, quality and utility. In addition to selective breeding and hybridization we can utilize mutant populations and biotechnology to have greater control over crop plant modification than ever before. Increasing the production of plant oils such as soybean oil as a renewable resource for food and fuel is valuable. Successful breeding for higher oil levels in soybean, however, usually results in reduced protein, a second valuable seed component. We show that by manipulating a highly active acyl-CoA: diacylglycerol acyltransferase (DGAT) the hydrocarbon flux to oil in …

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 …

Frost: Frequently Asked Questions, Department Of Primary Industries And Regional Development, Western Australia

Grain and other field crops published reports

Frequently asked questions regarding frost from the National Frost Initiative.

Establishing Peach Trees For Organic Production In Utah And The Intermountain West, Jennifer R. Reeve, C. M. Culumber, Brent Black, Andrew Tebeau, Corey Ransom, Diane Alston, M. Rowley, Thor Lindstrom

Plants, Soils, and Climate Faculty Publications

Adequate weed control and nutrient supply are critical for successful establishment of fruit trees. This is of particular concern in organic orchard establishment. In order to determine the best approach for establishing peach trees (Prunus persica L.) organically in climates characterized by hot dry summers and cold winters such as the North American Intermountain West, seven organic and three integrated and conventional treatment combinations were established in two first leaf orchards at the USU Kaysville Research Farm, Utah, in 2008 and 2009. Treatments consisted of different tree-row and alleyway mulch and fertilizer combinations. Compost or conventional fertilizer (16-16-16 and …

Effect Of The National Accelerated Agricultural Inputs Access Subsidy Program On Fertilizer Usage And Food Production In Kakamega County, Western Kenya, Abednego Kiwia Mavuthu

Walden Dissertations and Doctoral Studies

Despite 25 years of concerted efforts by African governments to adopt consistent policies for increasing food production, hunger and poverty are still prevalent in the continent. Using Bernanke's conceptualization of the credit channel theory of monetary policy, the purpose of this correlational study was to investigate whether a subsidy program, the National Accelerated Agricultural Inputs Access Program (NAAIAP), affected the rates of fertilizer usage and food production in Kakamega County, Western Kenya. Purposive stratified sampling was used to select 114 participants consisting of 72 farmers in each of the 2 groups: NAAIAP beneficiaries and nonbeneficiaries. Participants completed a survey on …

Polyphenolic Content And Antioxidant Capacity Of White, Green, Black, And Herbal Teas: A Kinetic Study, Emer Shannon, Amit Kumar Jaiswal, Nissreen Abu-Ghannam

Articles

Camellia sinensis teas, and tisanes derived from herbs or fruit, are rich in polyphenolic, antioxidant compounds. This study compared the total phenolic content (TPC), total flavonoid content (TFC), ferric reducing antioxidant power (FRAP), DPPH radical scavenging capacity, and caffeine content of teas (black, green, white, chamomile, and mixed berry/hibiscus) over a range of infusion times (0.5–10 mins) at 90°C. Green, followed by black tea, respectively, had the greatest TPC (557.58 and 499.19µg GAE/g), TFC (367.84 and 325.18µg QE/g), FRAP (887.38 and 209.38µg TE/g), and DPPH radical scavenging capacity (1233.03 and 866.39µg AAE/g). Caffeine content per cup (200mL) in black, green, …

Impact Of Push-Pull Technology On The Nutritional Status Of Farmers' Children In Western Kenya, Nicholas O. Ogot, J. O. Pittchar, C. A.O. Midega, Z. R. Khan

All Peer-Reviewed Publications

This study examined the impact of push-pull technology (PPT) on the nutritional status of children aged 1-12 years. Non-push-pull (NPPT) farmers were used as a control group to establish a comparative model for this study. It determined household production, consumption, and surpluses, comparing the PPT adopters to the nonadopters; found out the incomes and food expenditures from farm products; found out the household dietary diversity scores; and finally found the nutritional status of the two household groups. A six faceted household-level metrics was employed. A sample of 216 households that registered 326 children was derived. This study was conducted in …

Twenty-First Century Climate Change And Submerged Aquatic Vegetation In A Temperate Estuary: The Case Of Chesapeake Bay, Thomas M. Arnold, Richard C. Zimmerman, Katharina A.M. Engelhardt, J. Court Stevenson

OES Faculty Publications

Introduction: The Chesapeake Bay was once renowned for expansive meadows of submerged aquatic vegetation (SAV). However, only 10% of the original meadows survive. Future restoration effortswill be complicated by accelerating climate change, including physiological stressors such as a predicted mean temperature increase of 2-6°C and a 50-160% increase in CO2 concentrations.

Outcomes: As the Chesapeake Bay begins to exhibit characteristics of a subtropical estuary, summer heat waves will become more frequent and severe. Warming alone would eventually eliminate eelgrass (Zostera marina) from the region. It will favor native heat-tolerant species such as widgeon grass (Ruppia maritima) while facilitating colonization by …

Effects Of Silicon And Nitrogen Fertilization On Growth, Yield, And Leaf Rust Disease Development In Wheat, Maryamossadat Shahrtash

LSU Master's Theses

There are so many people who have helped me throughout my graduate studies and for whom I am grateful. I would like to take this opportunity to first and foremost thank God for his always guidance throughout my life and giving me the wisdom and the patience I needed to finish my thesis. I would like to thank Dr. Brenda Tubana for taking me in and providing me with guidance and knowledge. I also would like to thank my committee members, Prof. Brian D. LeBlanc who guided me, encouraged me and provided me with knowledge about sustainable agriculture and Dr. …

Evaluation Of The Microbial Quality Of Cantaloupe Fruit Produced On Raised Or Flat Beds Following A Flooding Event, Isaack Kikway

LSU Master's Theses

Floodwater can contain microbial contaminants such as plant and foodborne pathogens and can compromise the quality of fresh fruit and vegetables produced in Louisiana. The goal of this research was to determine the impact of flooding on microbial quality (foodborne and plant pathogens) of cantaloupe fruit produced on raised or flat beds. Cantaloupe fruit produced on 30 cm raised beds or flat ground, were flooded with a mixture of surface and well water spiked with three generic Escherichia coli strains (ATCC 23716, 25922, 11775). Mean baseline generic Escherichia coli and total coliform populations in flood water (mixture of spiked well …

The Roles Of Avr4 In Fungal Virulence,Cercosporin Biosynthesis And Its Potential Use In Host Induced Gene Silencing For Controlling Cercospora Leaf Blight Disease Of Soybeans, Josielle Santos Rezende

LSU Doctoral Dissertations

The AVR4 effector, secreted by Cladosporium fulvum, has been demonstrated to be involved in pathogen virulence. Recent studies further demonstrated that Avr4 is highly conserved among several Cercospora species, indicating a potential important role of this gene in fungal virulence. Therefore, investigation to determine whether this fungal effector gene is present in Cercospora cf. flagellaris (previously known as C. kikuchii), the causal agent of soybean cercospora leaf blight (CLB) disease, and whether it plays any role in CLB disease development, is of great interest. In the present study, the Avr4 gene from C. cf. flagellaris was cloned and mutants lacking …

The Spaghetti Tree, James P. Smith Jr

Botanical Studies

No abstract provided.

A Chronicle Of Economic Botany, James P. Smith Jr

Botanical Studies

No abstract provided.

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

College of Graduate Studies: Theses & 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 …

Vegetable And Fruit Intake And Fracture-Related Hospitalisations: A Prospective Study Of Older Women, Lauren C. Blekkenhorst, Jonathan M. Hodgson, Joshua R. Lewis, Amanda Devine, Richard J. Woodman, Wai H. Lim, Germaine Wong, Kun Zhu, Catherine P. Bondonno, Natalie C. Ward, Richard L. Prince

Research outputs 2014 to 2021

The importance of vegetable and fruit intakes for the prevention of fracture in older women is not well understood. Few studies have explored vegetable and fruit intakes separately, or the associations of specific types of vegetables and fruits with fracture hospitalisations. The objective of this study was to examine the associations of vegetable and fruit intakes, separately, and specific types of vegetables and fruits with fracture-related hospitalisations in a prospective cohort of women aged ≥70 years. Vegetable and fruit intakes were assessed at baseline (1998) in 1468 women using a food frequency questionnaire. The incidence of fracture-related hospitalisations over 14.5 …