Life Sciences Commons^™

Louisiana Agricultural Magazine, Spring 2025

Louisiana Agriculture

Growing fruits and pecans is a part of Louisiana’s agricultural heritage. Citrus trees have been planted here for three centuries, and the state is famous for strawberries. Pecans and mayhaws are native to the state, and they are beloved by Louisianans. Some of these fruits have become industries worth millions of dollars, while others have become popular for home production.

This issue of Louisiana Agriculture focuses on the efforts of LSU AgCenter Extension experts working to foster home fruit production and support the fruit and pecan industry in Louisiana. Through their research and extension programs, they provide homeowners and commercial …

Studies On Cell Cycle Regulation And Ecm Modification During Tubular Organ Formation In Drosophila Embryos, Jeffrey Matthew

LSU Doctoral Dissertations

The formation of tubular organs—such as the heart and kidneys—is a complex developmental process that requires the precise coordination of tissue remodeling with dynamic changes in cellular behavior. Key processes including cell proliferation, apoptosis, and extracellular matrix (ECM) formation must be tightly synchronized with mechanisms that generate and transmit physical forces, transforming a flat epithelial sheet into a three-dimensional organ. Disruptions in the homeostasis of these processes during organogenesis can lead to congenital defects, such as pulmonary atresia and renal hypoplasia.

To investigate the mechanisms underlying epithelial morphogenesis, the Chung laboratory employs the Drosophila embryonic salivary gland (SG) as a …

Rheological, Interfacial, And Filtration Behavior Of Lignocellulosic Nanomaterials In Suspension And Emulsion Drilling Fluids, Meen Sung Koo

LSU Doctoral Dissertations

In recent years, the rheological aspects of suspensions/emulsions applied by cellulose nanomaterials (CNMs) have been gained considerable interests due to high gel-forming properties ascribed by hydrophilicity, crystallinity, ease functionalization, and high aspect ratio. Introducing residual lignin in CNMs (LCNMs) seemed to be capable of achieving various advantages in the application of CNMs ascribed by hydrophobicity, binding effects, and abundant aromatic groups derived from complexity of lignin. This dissertation dedicates to the characterizations of (L)CNMs, and rheological properties of (L)CNMs applied fluids (i.e., suspension and emulsion). In the suspension system, the presence of lignin in LCNMs decreased gel strength, viscosity, and …

Impact Of Glufosinate On Sugarcane Yield And Yield Components When Applied Post-Directed And Its Efficacy In Controlling Emerged Itchgrass (Rottboellia Cochinchinensis), Warner R. Simon

LSU Master's Theses

Weed control is extremely important in the Louisiana sugarcane (Saccharum spp.) industry, as it is a perennial crop that grows back after each harvest. Fields are kept weed free using mechanical and chemical methods to prevent weed-crop competition and further establishment of weed populations. The weed itchgrass (Rottboellia cochinchinensis) has become problematic for Louisiana sugarcane producers. Sometimes, itchgrass can still emerge after farmers have made a pre-emergence (PRE) herbicide application. These weeds are usually controlled using the herbicide paraquat dichloride (paraquat) in post-emergence (POST) directed applications. In recent year, 2016-2024, the United States Environmental Protection Agency …

The Design, Construction, And Testing Of Mrna Vaccine Against Equine Herpes Virus, Bhawana Devkota

LSU Master's Theses

Equine Herpesvirus-1 (EHV 1) is a worldwide significant pathogen that causes respiratory illness, abortion, and neurological disorders in equine. Current vaccines, including live attenuated, inactivated, and subunit platforms, do not prevent viral latency, mucosal shedding, or cross-strain immunity, requiring alternative approaches. To address these gaps, this project explores the design, synthesis, and in vitro testing of an mRNA vaccine targeting immunogenic EHV 1 glycoprotein (gB, gC, gD, gG, and gM). Epitopes were computationally predicted using the Immune Epitope Database (IEDB), codon-optimized for Bos taurus, and cloned into pUCIDT vectors using SP6/T7 promoters. In vitro transcription (IVT) used nucleotide modifications …

Variation In Response To Phosphorus Among Sweetpotato (Ipomoea Batatas L.) Cultivars, Jeffrey Cole Denis Gregorie

LSU Doctoral Dissertations

Phosphorus (P) is essential for plant growth and is often a major limiting nutrient in agriculture. In sweetpotato (Ipomoea batatas), studies on the role of P on storage root yield have been limited because of the lack of response and inconsistent results across cultivars and years. Growing evidence shows that current phosphate (Pi) fertilizer rates can be reduced while maintaining productivity. Newly published molecular evidence shows differential expression of phosphate starvation response genes among sweetpotato cultivars, further supporting the hypothesis of cultivar-specific Pi sensitivity. The research herein sought to characterize root system architecture and yield response to Pi …

Corn And Soybean Responses To Phosphorus And Potassium Application Timings And Methods And Fertilizer Sources, Abrar Bin Wahid

LSU Master's Theses

This research was driven by concerns over phosphorus (P) and potassium (K) losses from fall-applied fertilizers and the increasing marketing popularity of liquid-P and K fertilizers over traditional granular-dry forms. We evaluated corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] yield and tissue nutrient concentration responses to fertilizer-P and K application timings, methods, and sources across 9-13 site-years on silt-loam soils in Louisiana from 2020-2024. For timing and method study, five treatments were evaluated: a no fertilizer-P and/or K check, fall broadcast followed by rehipping the seedbed, spring broadcast without rehipping, spring broadcast with rehipping, and spring top-of-bed …

The Eastern Oyster Behavioral Response To Low Salinity And Hypoxia In Controlled And Natural Settings, Siyah Yongue

LSU Master's Theses

Oyster aquaculture is expanding in the northern Gulf of Mexico, but climate change may challenge the sustainability of this industry. Projected increases in the frequency and intensity of low salinity and low dissolved oxygen (DO) periods could impact the behavior, metabolism, growth, and survival of oysters. Characterizing how oyster behavior links to environmental stressors could help better identify thresholds in their tolerance and inform predictive tools for aquaculture professionals. In this research, the effect of separate and concomitant exposures to low salinity and DO on the behavioral response of oysters was examined in the lab. The impact of other environmental …

Ghost Fishing Due To Derelict Crab Traps In Louisiana’S Barataria Basin, Emma C. Villemarette

LSU Master's Theses

Ghost fishing, the unintentional entrapment of sea life by derelict fishing gear, is an ecologic and socioeconomic concern in Louisiana's crabbing industry (blue crab, Callinectes sapidus). These ghost fishing traps cause unknown and unaccounted for mortality in blue crab and bycatch species. I aimed to track changes to derelict crab trap catch and trap deterioration over seasons and between habitats. I set and monitored 33 simulated derelict crab traps over 367 soak days in three varying habitats along Barataria Bay, Louisiana. Traps were checked once every two weeks and an additional daily check for five days per season. Blue …

Improving Fertilizer Efficiency In Containerized Nursery Production Through Substrate Temperature Management Techniques, Ashley R. Edwards

LSU Master's Theses

Resource efficiency, particularly regarding mineral nutrients, is a critical factor in the long-term success of the nursery industry. Fertilizer release is controlled by water and temperature in container-grown ornamental nursery production systems. Thus, it was hypothesized that pragmatic management of substrate temperature and moisture could extend the longevity of controlled-release fertilizer (CRF) in a container system. This study was conducted to determine the effect of irrigation scheduling, container color, and stratified substrates on substrate temperature and the subsequent use and longevity of CRF in a crop production setting. ‘Limelight’ Hydrangea (Hydrangea paniculata) liners were planted in either black …

Using Phylogenetics And Floral Evolution Of Sicklebill Hummingbird-Pollinated Centropogon Subgenus Centropogon To Support Undergraduate Research, Janet Mansaray

LSU Doctoral Dissertations

The genus Centropogon subgenus Centropogon, offers an ideal system for studying macroevolutionary patterns due to its diverse floral morphologies and specialized pollinator interactions. This subgenus comprises 55 species, mostly found in mid-elevation Andean forests, where many species exhibit abruptly curved flowers, often associated with pollination by sicklebill hummingbirds. Using phylogenomic approaches, we conducted the first densely sampled analysis of this group, confirming the monophyly of two sections. Our study highlighted extensive gene tree discordance, likely driven by incomplete lineage sorting. Floral curvature and inflorescence structure evolved in a correlated fashion, leading to multiple independent losses of traits linked to …

History, Annotated Gazetteer, And Bibliography Of Ornithology In Kalimantan, Indonesian Borneo, Frederick H. Sheldon, Mohammad Irham, Daisy G. S. Kho, Erik Meijaard, Subir B. Shakya, Dewi M. Prawiradilaga, Sebastianus (Bas) Van Balen

Occasional Papers of the Museum of Natural Science, Louisiana State University

Kalimantan comprises nearly three quarters of the island of Borneo and is the place where scientific study of Bornean birds began. We describe the history of bird research in Kalimantan from its beginning, highlighting the ornithologists who explored the region and how their interests and methods changed over time, from a concentration on specimen collection, to examinations of community ecology, to conservation in the face of habitat change and species depletion, to the latest investigations using satellite, genetic, and digital technology. We also highlight some future directions for research, especially the need for more work on basic ecology and biogeography. …

Louisiana Graduate Network In Applied Evolution (Lagniappe): 2024-2025 End-Year Report, Kristina G. Little, Samuel B. Robison, Bret Blackmon

Reports

The Louisiana Graduate Network in Applied Evolution (LAGNiAppE) is a post-baccalaureate program funded by the National Science Foundation (NSF) and hosted by the LSU Department of Biological Sciences. In its second year, the program provides recent college graduates with a structured, immersive research experience designed to prepare them for graduate education and careers in STEM. This report presents findings from the 2024–2025 program year (cohort 2) and is based on comprehensive evaluation data collected from Scholars, mentors, and co-mentors. The 2024–2025 cohort engaged in a wide range of activities, including intensive bootcamp training, independent research projects, scientific presentations, weekly seminars, …

Louisiana Agriculture Magazine, Winter 2025, Lsu Agcenter

Louisiana Agriculture

LSU AgCenter nutrition education programs have always aimed to support the health and well-being of Louisianans. Helping residents eat healthier, be more physically active and maintain a healthy weight are important parts of disease prevention. Building healthy, thriving communities across Louisiana can support reduced healthcare costs, improved workforce productivity and an enhanced quality of life for everyone in our state.

Co2 In Flowing Freshwaters: Macro Scale Database Compilation, Addressing Ph Bias In Co2 Estimates, And Quantifying Cross-Scale Interactions, Timothy R. Toavs

LSU Doctoral Dissertations

This dissertation focuses on carbon dioxide (CO₂) dynamics in flowing freshwaters, contributing to the growing body of knowledge about inland water carbon cycles. The research is structured into three main chapters, each progressing towards the objective of utilizing variability in flowing freshwaters to further understand carbon dynamics, anthropogenic land cover impacts, and potential impacts from a changing climate. Chapter one compiles a 30-year dataset of pCO₂ measurements from flowing freshwater systems across the contiguous United States. This dataset, referred to as CDFLOW, includes over 750,000 pCO₂ estimates from more than 35,000 locations. It serves …

Biological Control Of Roseau Cane Scale With Parasitoid Wasps In Louisiana, Tanner C. Sparks

LSU Doctoral Dissertations

Roseau cane scale, Nipponaclerda biwakoensis (Hemiptera: Aclerdidae) is an invasive species of scale insect negatively impacting Phragmites australis (Cyperales: Poaceae) stands within the Mississippi River Delta. The scales were first detected in 2017 from reports of Phragmites die-back within the MRD by landowners. Initial range surveys located RCS infested Phragmites stands were primarily limited to southeastern Louisiana with a single population near Port Arthur, Texas. Follow-up field surveys conducted annually from 2021 to 2023 monitoring further range expansion by the scale show the current range extends nearly 600 km between High Island, Texas and Bayou la Batre, Alabama. Climate matching …

Understanding Mechanisms For Coastal Marsh Sustainability In A Changing Climate, Ashley R. Booth

LSU Doctoral Dissertations

In the Chenier Plain of Louisiana and Texas, coastal marshes are subject to high rates of relative sea level rise (RSLR), restricted sedimentation, and declining elevation attributed to subsidence and decades of intensive management. These marshes were created via mineral sedimentation but now largely accrete via organic matter accumulation. This organic matter accumulation (OMA) – or the balance between plant productivity and decomposition – is essential for maintaining elevation and thus long-term sustainability. However, management for elevation is complicated by a poor understanding of how abiotic factors like flooding and salinity impact processes driving OMA and elevation. To better understand …

Evaluating Growth Of Coastal Grass In Recycled Glass Sand: Evidence For Safe Application In Coastal Restoration, Allison B. Huddleston

Honors Capstones

Louisiana’s coastal land loss results from complex interactions of anthropogenic and naturally occurring processes that impact sediment supply in the Mississippi river delta. Given the coastline's vital role in the state’s economy, Louisiana has made significant investments in coastal restoration projects, including planting native vegetation and adding borrowed sediments. The amount of sediment needed to maintain Louisiana’s existing coastline exceeds the available amount that could be extracted, and state officials have since identified this lack of sustainable sediment resources as a critical limitation for future restoration projects. One proposed solution to address this shortage is using recycled crushed glass cullet …

Addressing Knowledge Gaps In Disease Epidemiology And Detection Of Fungicide Resistance In Cercospora Leaf Blight Of Soybean, Stephanie Karen Ramos

LSU Master's Theses

Cercospora leaf blight (CLB) has been the primary foliar disease impacting the soybean crop in the mid-South for over a decade. A poor understanding of disease epidemiology and the prevalence of fungicide resistance have added complexity to management efforts. Recent findings suggest that airborne conidia play a significant role in the outbreak of CLB. We investigated the relationship between weather variables and conidial release using multi-site, multi-year spore trapping data. The findings confirm that C. cf. flagellaris is the dominant CLB pathogen, contributing significantly more conidia than C. cf. sigesbeckiae and C. kikuchii in soybean fields across Arkansas, Mississippi, …

Digital Agriculture Approaches: Uav-Based N Monitoring And Machine Learning For Maize Yield Prediction, And N Response Assessment Across Rice Varieties, Rejina Adhikari

LSU Master's Theses

Sustainable agriculture is essential for addressing global challenges such as food security, environmental degradation, and climate change while ensuring high productivity and resource conservation. Precision agriculture technologies, like UAV-based remote sensing and advanced sensors, offer tools to monitor real-time crop health, soil conditions, and nutrient levels, aiding in informed decision-making and resource optimization. In this research, field trials were conducted in maize and rice to assess the effectiveness of NDRE (Normalized Difference Red Edge) obtained from UAV-based remote sensing for nitrogen management. For maize, the study demonstrated that NDRE accurately assessed nitrogen levels during critical growth stages, with yields ranging …

Determining The Impact Of Lethal Temperature And Relative Humidity When Combined With Various Insecticide Classes Against A Bed Bug (Cimex Lectularius) Population., Bandana Shrestha

LSU Master's Theses

Common bed bugs (Cimex lectularius) are obligatory blood-feeding pests that have adapted well to survive in challenging environmental conditions. Known for their high tolerance to dehydration, low water loss, and high critical thermal maximum, they have become difficult to manage. Environmental factors, particularly temperature and humidity, play a significant role in their survival. However, with growing resistance to insecticides, integrated pest management (IPM) strategies are now essential for effective bed bug control. A key strategy in IPM involves combining insecticides with heat treatments. This method aims to overcome the limitations of heat treatment alone, as bed bugs may …

Eastern Baccharis Control In Newly Planted Wetland Reserve Programs, Lucas Stamper

LSU Doctoral Dissertations

The Lower Mississippi Alluvial Valley is a high-priority region for restoration of bottomland hardwood forests. Restoration of these forests is facilitated through conservation easement programs, such as the Conservation Reserve Program (CRP) and the Wetland Reserve Program (WRP), which focus on retiring marginal agriculture land and restoring bottomland hardwoods. A prominent issue that reduces hardwood establishment success is the failure to suppress competing vegetation, like eastern baccharis (Baccharis halimifolia L.), that aggressively colonize a site after seedlings are planted. Eastern baccharis is a frequent woody invader of disturbed bottomland sites throughout northeast Louisiana. There are few chemical options for …

Effects Of Retinal Gonadotropin-Releasing Hormone On Reproductive Behavior And Retinal Activity In The Cichlid Fish, Astatotilapia Burtoni, Chase Anselmo

LSU Master's Theses

Many animals use visual signals to evade predators, forage for food, and communicate with conspecifics. Some animals that shift into and out of breeding stages, such as fish, can modulate their visual sensitivity to better adapt to changing internal and external conditions. Previous work in our lab demonstrated that females of the cichlid fish Astatotilapia burtoni have improved visual sensitivity when they enter reproductive readiness. However, little is known about how fish and vertebrates more broadly modulate visual sensitivity across their reproductive cycle. We hypothesized that the hormone and neuromodulator gonadotropin-releasing hormone (GnRH) could modulate visual sensitivity because GnRH is …

Improving Rice Yield Using Sensor Based Nitrogen Application And Best Management Practices (Bmps) In Rice-Soybean And Rice-Crawfish Rotational Systems, Charles Darnall

LSU Master's Theses

Sustainable rice farming requires effective nutrient management and conservation practices to maintain high yields and minimize environmental impact. Implementing best management practices (BMPs) promotes lower fertilizer application rates, increased N use efficiency, improves soil health, and water quality. Demonstration fields established in two different rotational cropping systems (rice-soybean and rice-crawfish) in Kaplan, LA in 2023. In each rotation system, the benefits of BMPs (sensor based mid-season N management and cover cropping) compared to farmer’s practice (FP) were evaluated using yield, yield components, soil and water quality as metrics. The rice-soybean fields in 2023 and 2024 were both planted with PVL03 …

Evaluation Of Nematicides For Management Of Plant-Parasitic Nematodes In Sugarcane, Iris M. Aguilar

LSU Master's Theses

Plant-parasitic nematodes (PPN) are an understudied threat in sugarcane production. Previous survey work showed that Tylenchorhynchus (stunt nematode), Pratylenchus (lesion nematode), Mesocriconema (ring nematode), and Helicotylenchus (spiral nematode) are the primary PPN genera found in sugarcane fields in Louisiana. This study evaluated the impact of nematodes on sugarcane growth and the effect of nematicides on nematode population densities. Greenhouse studies were conducted using soil collected from multiple sugarcane fields with moderate PPN infestation levels to determine the nematode impact on sugarcane growth and nematicide efficacy. Field soil collected from each site was subjected to four treatments: an untreated and sterilized …

Evaluation Of Wood Fibers Derived From Different Tree Species And Processing Methods On Crop Growth And Microbial Activity In Soilless Substrates, Amanda Mizell

LSU Master's Theses

Soilless culture use is expanding as arable land and viable fumigants have decreased in availability. This has subsequently increased the demand for soilless substrates for container crop production. The primary component in most soilless substrates is Sphagnum peat moss, which is considered unsustainable due to the extensive time it takes to produce and the release of large amounts of carbon into the atmosphere during harvesting. Research into viable peat moss amendments to reduce reliance on this relatively non-renewable material has become a necessity. The most promising amendment that has been accepted in the horticulture industry as a viable amendment is …

The Role Of Siamese In G2 Checkpoint Regulation In Arabidopsis Thaliana, Martha A. Schwall

LSU Doctoral Dissertations

Cyclin-cyclin dependent kinase (Cyclin-CDK) pairs regulate progression through the checkpoints of the cell cycle. They bind with some specificity and must be bound to for their regulative properties to be active. The presence of cyclin-CDKs is conserved throughout eukaryotes, while differences in specifics exist between yeast, animals, and plants. In Arabidopsis, SIAMESE (SIM) is a CDK inhibitor that restricts progression through mitosis. Overexpression of SIM is required for endoreplication in Arabidopsis trichomes, and overexpression of SIM results in increased endoreplication in leaf epidermal cells. SIM is expressed at high levels in the root elongation zone, where it plays a …

Exploring The Interconnectivity Between Soilless Substrate Hydraulic Properties And Plant Root Morphology, Kristopher S. Criscione

LSU Doctoral Dissertations

Horticultural container production heavily relies upon porous soilless substrates to mass produce specialty crops. Soilless substrates are responsible for continuously maintaining optimal water, mineral nutrients, and air balances to promote healthy root growth and support productive shoot yield (foliage or fruit). Increasing evidence of substrate research continues to highlight the strong relationships associated with root development and substrate physiochemical properties. Despite the importance of the root system for overall plant health, most horticultural research to-date has focused on shoot development. Research tends to report total root biomass as the primary root-growth metric; however, this results in several developmental features becoming …

Analyzing The Catfish And Trout Competitiveness Trends And Potential Trade Within The Us And Global Aquaculture Industry: A Gravity Model Approach, Diana Marisol Amaya Discua

LSU Master's Theses

The United States is one of the major seafood product importers in the world. Despite the increases in global seafood and aquaculture consumption over the past decades, there is limited information on the trade dynamics of this sector. To address this gap, this study uses an augmented gravity model to evaluate the factors that have influenced catfish and trout imports into the United States. The analysis was conducted using the Poisson Pseudo Maximum Likelihood (PPML) estimator to address issues of heteroskedasticity, autocorrelation, and zero trade flows. The results highlight the importance of Gross Domestic Product (GDP) and exchange rates in …

Identification And Characterization Of Resistance To Meloidogyne Enterolobii And M. Incognita In Sweetpotato Genotypes, David M. Galo Espinal

LSU Doctoral Dissertations

Root-knot nematodes (RKN), Meloidogyne spp., are significant agricultural pests that cause severe economic losses on a wide range of agricultural crops worldwide, including sweetpotato. The economic viability of the sweetpotato industry in the United States is threatened by Meloidogyne enterolobii, which reproduces on sweetpotato cultivars resistant to other RKN species. To address this issue, 69 sweetpotato genotypes were evaluated to identify sources of resistance to M. enterolobii (Me) and M. incognita (Mi). Results showed that twenty-six genotypes were highly resistant to Me and eleven were resistant to Mi, with three genotypes showing resistance to …