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Louisiana Agriculture Magazine, Fall 2024

Louisiana Agriculture

Questions drive the science behind the LSU AgCenter. Researcher Erin Oberhaus wanted to find data to help educate Louisiana horse owners about the use of an important medication, and a water quality specialist wondered if noneconomic bodies of water, which include agricultural ponds, might help people generate electricity. The research projects that grew from their questions are detailed in this issue of Louisiana Agriculture.

Also in this issue, scientists share the results from important soybean studies, and the AgCenter farm to school team shares success stories from school gardens across the state.

Research is at the core of the LSU …

Louisiana Graduate Network In Applied Evolution (Lagniappe): 2023-2024 End-Year Report, Kristina Little, Samuel B. Robison, Bret Blackmon, Andrew R. Burns

Reports

The Louisiana Graduate Network in Applied Evolution (hereinafter; LAGNiAppE) was funded by a grant awarded through the National Science Foundation (NSF 22-506), as part of the Research and Mentoring for Postbaccalaureates in Biological Sciences (RaMP) grant program. The LAGNiAppE program provides training and mentorship to cohorts of recent college graduates from underrepresented groups interested in advancing their knowledge and research skills in evolutionary biology. Social Research and Evaluation Center (SREC) at Louisiana State University conducted the evaluation of LAGNiAppE, assessing program implementation and impact. The evaluation team at SREC employed a mixed methods design that included online surveys for scholars …

Improving Bovine Intracytoplasmic Sperm Injection, Lauren Gatenby

LSU Doctoral Dissertations

Despite large efforts, there has been minimal improvements in bovine intracytoplasmic sperm injection (ICSI) in the last few decades. In this study, we investigate methods to improve embryo development rates with ICSI in cattle through addressing sperm and oocyte factors and modifying injection methods. Inducing the acrosome reaction in bull sperm prior to injection with progesterone increased cleavage (46.2% vs 16.2%) and blastocyst (21% vs 3.8%) rates compared to controls, respectively. Supplementing glutathione during in vitro maturation of the oocyte did reduce free reactive oxygen species (ROS) in the oocyte, but did not improve embryo development rates with ICSI or …

A Comparison Of Diploid And Triploid Eastern Oysters For Aquaculture Production Under Extreme Temperatures And Salinities, Joshua H. Kim

LSU Master's Theses

Off-bottom aquaculture of Eastern oysters (Crassostrea virginica) is a nascent industry that is increasingly supported by the use of triploid oysters, which grow faster than diploids. Despite their growth advantage, elevated triploid mortality compared to diploids under high temperature, low salinity, or a combination of these conditions challenge consistent triploid production. Identifying the environmental thresholds at which differential triploid mortality occurs and predicting its economic impact are important to informing decision-making in oyster aquaculture. The goal of this thesis was to compare the biological and economic performance of diploid and triploid oysters under high temperature and low salinity conditions. …

Susceptibility Of Spodoptera Frugiperda And Helicoverpa Zea Populations In The Southern Region Of The United States To Common Chemical Insecticides, Bhavana Patla

LSU Master's Theses

Abstract

The fall armyworm, Spodoptera frugiperda and corn earworm/bollworm, Helicoverpa zea, are two polyphagous pests prevalent in the U.S. In recent years, there were increased infestations of the two pests in the U.S., especially in its southern region. Information on the susceptibility/resistance status of the two pests in the region to chemical insecticides, especially to some new chemistries, is very limited or has not been updated for many years. In this study, susceptibility of 17 S. frugiperda and six H. zea field collected populations from the southern U.S. during 2021-23 to common insecticides was investigated in the laboratory. Dose-responses with …

The Behavioral Specialization Of African Ant-Following Birds On Dorylus Driver Ants, Patricia F. Rodrigues

LSU Doctoral Dissertations

Ant-following birds, that forage on arthropods flushed by swarm raiding army ants, are an iconic phenomenon in tropical forests around the globe. Despite capturing the attention of naturalists for over a century, research on ant-following birds has largely focused on Neotropical species. Decades of research on Neotropical ant-following birds has revealed fascinating aspects of their specialization, including complex cognitive and behavioral adaptations that allow birds to locate and track nomadic army ants. Despite this breadth of research on Neotropical species, virtually nothing is known of the behavioral ecology of African ant-following birds, and it remains unknown whether they exhibit adaptations …

An Exploration Of The Drivers Of Intraspecific Variation In Arthropod Phenotypes, Jamie Phelps

LSU Doctoral Dissertations

Herein we explore the various forces that drive phenotypic variation in arthropods focusing on spatial and temporal differences as well as sexual dimorphism. We use both marine, Tigriopus californicus, and terrestrial, Melitaeini, organisms to investigate these forces.

Tigriopus californicus and Heat Hardening: The study explores how Tigriopus californicus, a copepod, adapts to thermal variation along the North American Pacific Coast. Researchers investigated intraspecific variation in heat hardening, measuring differences in upper lethal limits (ULLs) and potential fecundity costs across five populations. We found a cost of heat hardening: the size of the first brood produced after heat shock …

Role Of Acute Alcohol Exposure In Klebsiella Pneumoniae-Induced Pneumonia, Prantho Malakar Dipta

LSU Master's Theses

Klebsiella pneumoniae (KP), a Gram-negative bacterium, induces severe pneumonia associated with devastating pathological consequences in the lung, such as substantial parenchymal damage. K. pneumoniae is responsible for causing life-threatening lung infections in patients with alcoholics and diabetics. The need to look for new therapeutic approaches is due to the emergence of Klebsiella pneumoniae strains that are resistant to many drugs. The effects of acute alcohol consumption on the host’s innate immune response to KP during infection remain unclear. Age-matched C57BL/6 female mice were administered 6g/kg of 32% alcohol or same amount of PBS via oral gavage 30 minutes prior to …

The Impact Of Xenophobia On Agricultural Trade In South Africa, Maxwell Peprah Amponsem

LSU Master's Theses

The growing number of farm attacks and xenophobia is one of the most serious crime issues facing the South African government. This study examines the impact of xenophobia on agricultural trade, using port-level trade data and xenophobia incident records from 2010 to 2023. Utilizing fixed effects Ordinary Least Squares (OLS) specifications, I find a significant negative impact of xenophobia on agricultural exports, while non-agricultural trade remains unaffected. These findings highlight the need for targeted policy interventions to combat xenophobic violence and stabilize the agricultural sector, ensuring the continuity of South Africa's trade and economic growth.

Application Of Automated Radio Telemetry To Explore Space Use Of Golden-Cheeked Warblers (Setophaga Chrysoparia), Michael Gamble

LSU Master's Theses

Understanding the spatiotemporal ecology of birds is essential to inform conservation and management decisions that could help maintain bird populations and reverse current population trends. Advancements in automated radio telemetry systems (ARTS) may improve our ability to monitor animal movements continuously and simultaneously but require further testing and development to maximize their benefits for wildlife research. My goals were (1) to investigate the use of automated telemetry to track fine-scale songbird movements in a forested environment, and (2) to use automated telemetry to quantify home range size, spatial overlap between home ranges, and extraterritorial forays for male and female golden-cheeked …

Digital Agriculture Applications In Maize Nutrient Management And Soybean Crop Stands Assessment, Bhawana Acharya

LSU Master's Theses

High soil moisture from frequent excessive precipitation can reduce maize (Zea mays L.) yield and increase nitrogen (N) loss. Early-stage soybeans (Glycine max) are also susceptible to damage under these conditions. Traditional methods for assessing N status in maize and plant stands in soybean are labor-intensive and time-consuming. In this study, UAV remote sensing was used to assess maize N status under different N rates and excessive soil moisture. For soybeans, we compared a blob detection method with the YOLOv8 model to estimate plant density using ground images from a handheld camera. Additionally, YOLOv8 performance was evaluated …

Leveraging The Genomic Tools To Explore The Molecular Basis Of Salinity Tolerance In Rice And Soybean, Rajat Pruthi

LSU Doctoral Dissertations

Salinity stress significantly challenges agricultural productivity, particularly affecting major crops like rice and soybean. This research investigates the genetic basis of salt tolerance in both crops through high-resolution genetic mapping, genome-wide association studies (GWAS), and RNA-Seq analysis. In rice, we examined quantitative trait loci (QTLs) associated with salt tolerance at the seedling and flowering stages using a population of advanced backcrossed introgression lines (ILs). A genetic map, constructed with 14,230 polymorphic SNP markers, identified distinct QTLs and candidate genes for salt tolerance at both stages, suggesting differential genetic controls. Notable genes such as OsHAK13 and OsCYP21-4 were upregulated under salt …

The Role Of Sexual Network Core Groups In Disease Epidemics, Jason Janeaux

LSU Doctoral Dissertations

Sexually transmitted infections (STIs) remain an economic and social burden, non-discriminately affecting sexually active individuals worldwide. The unique transmission of STIs is dependent upon host and pathogen life histories, as well as the underlying network structure of the host population. Within a population there is a group of individuals, the core group, that maintains STI presence and helps sustain ongoing transmission both within the core group and in the surrounding population. While the presence of these core groups is well documented, the criteria for inclusion into a sexual core group is not. In this dissertation, I explore common factors that …

Revisionary Taxonomy Within The Acmaeoderini, Joel Dubois

LSU Master's Theses

The jewel beetles (Coleoptera: Buprestidae) are the 8th largest family of beetles and fill various important ecological roles including decomposers, pollinators, and leaf miners. The cosmopolitan buprestid tribe Acmaeoderini is extremely diverse, with more than 700 species across 14 genera. Historically, the acmaederines from Afro-Eurasia have received thorough morphological treatment and nearly all species from these areas have been separated into various genus and subgenus groupings. Contrastingly, past studies in the Americas have been mostly restricted to alpha-level taxonomic descriptions, and only a very small percentage of species are placed into any formal group. The aim of this study was …

Impact Of Containment And Elevation On Created Marsh Plant Community And Ecosystem Dynamics, Kevin R. Stoner

LSU Master's Theses

Coastal marsh restoration is increasing globally, as marshes are impacted by anthropogenic impacts. Billions of dollars are allocated to marsh restoration in the Mississippi River delta where wetland loss rates are extremely high. The recovery of structural and functional attributes of created marshes varies by attribute measured and project. Here, two marshes created in 2018 and one natural marsh were used to examine how variations in hydrologic connectivity and marsh elevation influence subsurface hydrology and salinity, vegetation community structure, soil properties, accretion, and denitrification. I established a comparative field study in a created marsh contained within a higher elevation containment …

The Design, Construction, And Testing Of Nucleic Acid Vaccines Against Salmonella Enterica Subspecies Enterica Serovar Javiana, Alexis A. Nguyen

LSU Master's Theses

Salmonella spp. is a Gram-negative bacterium that has the ability to replicate within a variety of hosts, or within the environment, including water, soil, and vegetation. These characteristics, coupled with the zoonotic nature of non-typhoidal Salmonella, pose a significant public health concern. Salmonella is the leading cause of foodborne illnesses worldwide, and in the United States alone, the economic impact due to non-typhoidal Salmonella illnesses in 2013 was estimated to be $3.7 billion, the majority of which were due to mortalities. In a time of rising antibiotic resistance, antibiotics are no longer considered the most effective treatment for …

Louisiana Agriculture Magazine, Summer 2024, Lsu Agcenter

Louisiana Agriculture

When the first agricultural experiment stations were founded in Louisiana more than 130 years ago, researchers focused on ways to improve the lives of farmers across the state. They found the best methods for raising cash crops and livestock along with the fruits and vegetables grown to feed the average rural family. Today the LSU AgCenter maintains that long legacy of research and expands its scope.

This issue of Louisiana Agriculture acknowledges those who helped establish the system of research and extension that would grow into the AgCenter. In addition to these articles, the scientists and staff at the AgCenter …

The Hoof Inside Out: A Comprehensive Investigation About The Shoe Configuration Effects On The Behavior Of The Equine Hoof, Rita Aoun

LSU Doctoral Dissertations

The equine hoof is a unique organ in biology that has intricate elastic properties. From simple protection to therapeutic and corrective measures, horseshoes are widely used in the equine industry. Various types of shoeing have been designed and used based on their unique targeted functions following hoof care. Shoes can modify the gait of the horse, affect the alignment of the distal joints, and alter stress and strains on specific hoof regions. The objective of this dissertation is to provide an overview of the available research on the existing methodology and literature on the effects of shoeing on equine gait …

The Effect Of Season On Neuroendocrine Interactions In The Mare, Victoria N. Bailey

LSU Doctoral Dissertations

Reproductive seasonality in the mare involves various neuroendocrine modulations, and a series of experiments were conducted to investigate the anatomical and physiological roles of some of these seasonal modulators. The first experiment incorporated kisspeptin-10 (Kp10) into a treatment with estradiol benzoate (EB) and sulpiride, aiming to induce early cyclicity in seasonally anovulatory mares. Incorporation of Kp10 resulted in more mares ovulating earlier compared to mares receiving EB-sulpiride. Although plasma prolactin increased in both groups, concentrations were notably higher in Kp10-treated mares. Therefore, the subsequent experiment explored the anatomical interaction of kisspeptin and prolactin, aiming to determine whether kisspeptin may regulate …

Evaluating Past Progress And Assessing Prediction Breeding Strategies For Sustained Genetic Gains In The Louisiana Sugarcane Variety Development Program, Brayden A. Blanchard

LSU Doctoral Dissertations

The aim of this dissertation is to outline important considerations for the Louisiana Sugarcane Variety Development Program (LSVDP) as it pertains to historical progress, impact, goal setting, and new strategies for continued genetic gains. Industry progress was evaluated with robust regression models to quantify rates of productivity gains. Over the last 50 years, statistically significant productivity gains were identified in sucrose content (45%), cane yield (32.2%), and sugar yield (93%) while pairwise comparisons of decades showed that progress was incremental rather than rapid and sustained once achieved. The decade from 1990-1999 was identified as the only decade with a significant …

Farmer's Adaptive Capacity And Adoption Of Strategies To Climate Change Among Mountain Communities In Nepal, Tanvir Hossain

LSU Master's Theses

Climate change presents significant challenges to agriculture worldwide, particularly where farming is central to livelihoods. This phenomenon has been linked to decreasing crop yields due to rising temperatures and reduced rainfall, particularly affecting low-income countries with limited adaptive capabilities. Grasping how farmers perceive climate change is essential for developing effective adaptation strategies to lessen its adverse impacts. This study concentrated on investigating the perceptions and adaptive strategies employed by smallholder farmers in Nepal's Mustang district, utilizing primary data sources. Data from 131 randomly selected households were gathered through structured interviews, while focus group discussions provided qualitative insights into farmers' views …

Methods To Manage Survey Error Within Economic Contribution Analysis, Madison Jane Plaisance

LSU Master's Theses

The primary objective of this research was to employ strategical methodological approaches to assess the economic value of specific sub-sectors of the green industry within Louisiana. I specifically focused on addressing errors associated with utilizing survey data as the primary data source in such analyses and utilizing approaches such as post-survey stratification and bootstrapping techniques to mitigate these errors.

To achieve this aim, a group of green industry professionals and I selected sectors for analysis based on horticultural licenses issued by the Louisiana Department of Agriculture and Forestry (LDAF). Through collaboration with advisors from the Louisiana Nursery and Landscape Association …

Extreme Climate Events And Agricultural Commodity Markets, Mohammad Abir Chowdhury Shovon

LSU Master's Theses

This article investigates the impact of extreme climate events on U.S. agricultural commodity markets, specifically focusing on corn and soybeans. Using event study methods and a comprehensive dataset of 254 extreme climate events for corn as well as 250 extreme climate events for soybeans in top ten corn & soybeans producing states of the USA between 1995 and 2023, we examine how storms, floods, extreme temperatures, and droughts affect the abnormal returns of these commodities. Our findings indicate that 22.04% of climate events significantly impact corn returns and 21.20% of climate events have significant impact on soybeans returns. Notably, extreme …

The Influence Of Stage Of Ripeness On Consumer Perceptions Regarding Selected Aspects Of Non-Astringent Asian Persimmons (Diospyros Kaki Thunb), Robert A. Mirabello Jr

LSU Doctoral Dissertations

Asian Persimmon (Diospyros kaki Thunb.) is an important fruit crop in Asia and in recent decades has experienced expanding production around the world. Non-astringent cultivars are highly desirable in world markets. In the United States the Asian Persimmon is lesser known and consumed although it can be successfully grown in California and the Southeastern United States.This novel study examined the physical/chemical properties of the non-astringent Asian Persimmon ‘Jiro’ grown in Southern Louisiana at three distinct stages of ripeness described as Green (mid-September harvest), Light Orange (mid-October harvest) and Dark Orange (mid-November harvest). Data collected included color, weight, size, soluble …

Characteristics Influencing Enrollment Choices: A Mixed Methods Analysis Of Factors That Influence Black Students' Decision To Enroll In College Of Agriculture Programs, Jennifer L. Brown

LSU Doctoral Dissertations

This study aims to identify the barriers that affect Minority enrollment in agriculture, particularly focusing on increasing the enrollment of Black students. There is a significant concern regarding the gap between Black individuals and agriculture enrollment in post-secondary agriculture programs at land-grant institutions. The purpose of this mixed method phenomenology was to (1) identify factors that influence the decision of Black students to enroll in the College of Agriculture and (2) uncover the societal and economic influences that continue to serve as barriers to Black students’ enrolling in agriculture. The quantitative portion of the investigation utilized a web-based instrument structured …

Optics Design And Fabrication For A Lung Interferometry-Radiography System, Rachael Lyn Blair

LSU Master's Theses

Purpose: High prevalence of lung diseases leads to many people worldwide needing spirometry and imaging testing. The typical imaging done uses chest radiography and/or low-dose CT. Lung tissue is difficult to visualize, making them substandard for monitoring lung disease progression. An improvement on these systems is x-ray interferometry which produces additional images that provide better visualization of changes in the lung tissue. The set-up of x-ray interferometry builds upon other imaging systems in that it includes diffraction gratings.

Materials: This thesis focused on implementing the fabrication processes to create diffraction gratings for a lung imager prototype that is currently under …

Impact Of Early-Season Postemergence Co-Applications Of Foliar And Residual Herbicides On Crop Injury, Growth, And Yield In 2,4-D- And Dicamba-Tolerant Cotton (Gossypium Hirsutum L.), Logan N. Vallee

LSU Master's Theses

Studies were conducted in 2021 through 2023 at the LSU AgCenter Dean Lee Research and Extension Center near Alexandria, LA to determine the sensitivity of 2,4-D- or dicamba- tolerant cotton (Gossypium hirsutum L.) to an early season application of a Group 15 and foliar-only herbicides. Both studies were randomized complete block designs with a two-factorial arrangement of treatments with four replications. In the dicamba-tolerant cotton study, Factor A consisted of no foliar-herbicide, dicamba alone, glyphosate alone, or dicamba plus glyphosate. Factor B consisted of either no Group 15 residual herbicide, acetochlor, or S-metolachlor. In the 2,4-D- tolerant cotton …

Benthic Community Response To The Impacts Of Proposed Sediment Diversions In Louisiana Estuaries, Jillian C. Tupitza

LSU Doctoral Dissertations

Sediment diversions designed to mitigate land loss in coastal Louisiana will likely cause ecosystem-wide shifts. The first diversion, planned for Barataria Bay, will divert fresh water and sediment from the Mississippi River into the surrounding wetlands to help them keep pace with high rates of relative sea-level rise (RSLR). Estuarine benthic communities were used in this study as tools to characterize ecological patterns in the context of anticipated salinity changes. I reviewed relevant literature, conducted a two-year survey of Barataria Bay benthos, executed a reciprocal transplant experiment to describe changes that might occur in both community composition and trophic dynamics, …

Harmonizing Soybean-Associated Beneficial Bacteria For Sustainable Cultivation, Jonas J. Padilla

LSU Master's Theses

Long-term reliance on agrochemicals, such as fertilizers and pesticides, to improve crop productivity can severely impact soil physicochemical properties and health. This eventually leads us to completely depend on these chemicals to sustain the needs of our crops. To resuscitate the deteriorating state of our arable lands, we need to shift from traditional farming to more sustainable crop management. One of the alternatives that we can use instead of these chemicals is the utilization of microorganisms that can perform a variety of beneficial functions for the growth and development of crops. Recently, seed-treating materials made up of bacterial consortia were …

Ammonium Chemotaxis In Chlamydomonas Reinhardtii, Gabela Nelson

LSU Doctoral Dissertations

Analysis of ammonium chemotaxis in Chlamydomonas reinhardtii is largely hindered, compared to that of phototaxis, despite equal importance on flagellated microalgal physiology. A major contribution of this shortfall is the lack of proper assay method. We developed a simple Petri dish assay method in which light is homogenously exposed while patterns of the cellular migration are tracked with a function of time. Using the method, new findings were revealed. First, this research presented that a strain lacking the eyespot organelle required for light gradient-sensing exhibits similar chemotactic behavior compared to a wild-type strain, suggesting Chlamydomonas sense an ammonium gradient not …