Agriculture Commons^™

Farm Workers And The Structural Basis Of Climate Change Perceptions, Cody Mortell, Anna Erwin, Zhao Ma, Dongkyu Kim, Elizabeth Rodriquez, Marla Perez-Lugo

School of Earth, Environmental, & Marine Sciences Faculty Publications

Farm workers are particularly vulnerable to climate change, especially from extreme heat; however, little is known about how they perceive this risk. This study examines climate change perceptions (CCP) among 404 farm workers surveyed in person in the Lower Rio Grande Valley, Texas from April to May 2024. Guided by Pierre Bourdieu’s theory of practice, we conducted a latent class analysis of economic, cultural, social, and symbolic capital indicators to identify distinct class profiles. We then assessed CCP by latent profile, using two primary outcome variables: (1) perceived temperature trends in the region (assessed alongside NOAA data) and (2) perceived …

Agrivoltaic Shading Reduces Soil Greenhouse Gas Fluxes In A Semi-Arid Vineyard, Marcelo Gomes Da Silva, Rafael M. Almeida, Carine Cocco, Engil Pereira

School of Earth, Environmental, & Marine Sciences Faculty Publications

Agrivoltaic systems are expanding in semi-arid regions, raising questions about how panel driven shading alters soil greenhouse gas exchange. We used automated chambers to measure high frequency soil CO2, N2O, and CH4 fluxes in a newly established vineyard agrivoltaic system in Texas across three shading intensities (0%, 35%, 88%) that represent the light environment beneath panels as shaped by panel tilt and solar trajectory. Shading primarily cooled the soil, reducing mean soil temperature from 35.9 °C (0%) to 32.5 °C (35%) and 30.5 °C (88%), while mean soil water content shifted modestly (0.125, 0.106, and 0.130 m3 m−3, respectively). Over …

Do Cover Crops Influence Beneficial And Herbivorous Arthropod Communities Across Growing Seasons?, Adegboyega Fajemisin, Satinderpal Kaur, Alejandro Vasquez, Alexis Racelis, Rupesh R. Kariyat

School of Earth, Environmental, & Marine Sciences Faculty Publications

Cover crops provide multiple ecosystem services in agriculture, yet their influence on arthropod communities remains poorly understood, especially in commercial farming. Despite their potential benefits, it remains unexplored how cover crops affect arthropod community dynamics across multiple growing seasons. We conducted a two-year study across three commercial farms in the Lower Rio Grande Valley, Texas, to examine how cover crops influence arthropod community composition and abundance, whether beneficial arthropods (natural enemies and pollinators) persist into cash-crop phases, and how cover crops affect natural enemy–herbivore relationships. We compared arthropod communities between cover-crop treatments and control plots and tracked responses through subsequent …

Analyzing Criteria Air Pollutants And Meteorological Parameters In The Rio Grande Valley, Laredo, And Corpus Christi Region Of South Texas, Angela Garcia

Theses and Dissertations

Recently, the Rio Grande Valley has experienced significant population growth due to economic opportunities, cross-border commerce, SpaceX, and the Rio Grande and Texas liquid natural export terminal presence. The Rio Grande Valley has an estimated population of 1,368,723. This region is largely understudied, along with nearby urban centers such as Laredo and Corpus Christi. The Rio Grande Valley and Laredo regions are a concern due to their population growth and heavy cross-border transportation. Data from the Texas Commission of Environmental Quality Continuous Ambient Monitoring Sites was collected from January 1st , 2024, to December 31st, 2024. Statistical analysis, such as …

Molecular Adaptation Of Sweet Potato To Martian Soil Simulant: Insights From Mrna And Long Non-Coding Rna Analyses, Subramanyam Reddy Chinreddy, Karthik Chinnannan, Purushothaman Natarajan, Vaibhavi Patel, Gwonjin Lee, Manohar Chakrabarti, Padma Nimmakayala, Umesh K. Reddy

School of Integrative Biological & Chemical Sciences Faculty Publications

Introduction: Understanding how crops adapt to extraterrestrial environments is essential for sustainable space agriculture. Sweet potato (Ipomoea batatas), a nutritionally rich and stress-resilient crop, is a promising candidate for cultivation under Martian-like conditions, characterized by high salinity, heavy metal contamination, and poor water retention.

Objective: This study aimed to elucidate the molecular mechanisms underlying sweet potato adaptation to Martian soil analog conditions using Mars Global Simulant-1 (MGS-1).

Methods: Leaf, shoot, and storage root tissues of sweet potato grown in MGS-1 were subjected to RNA sequencing. Differentially expressed mRNAs and long non-coding RNAs (lncRNAs) were identified, and functional enrichment analyses were …

Systematic Synthesis Of Crispr/Cas Applications For Enhancing Salt Tolerance In Crops: A Decade Of Progress And Challenges, Xindi Sun, Fusheng Wu, Zhuanzhuan Ma, Guohao Liang, Shumei Chen, Xutong Hu, Shugao Fan, Ying Zhao

School of Mathematical & Statistical Sciences Faculty Publications

Soil salinity is a major constraint on global crop productivity, driving the need for salt-tolerant varieties. While CRISPR-Cas genome editing offers targeted solutions for trait improvement, significant biological and technical bottlenecks limit its application in conferring salt stress resilience. This systematic summarizes findings from 83 peer-reviewed studies (2015–2024) employing CRISPR/Cas technologies to improve salt tolerance in five major crops (rice, wheat, maize, sorghum, barley). Our systematic review reveals that early single-gene edits achieved modest gains (30–50% Na⁺ exclusion) but often showed limited yield gains in field settings, potentially due to compensatory regulation and environmental variation. The literature suggests that multiplex …

Weather Conditions Associated With Citrus Canker Incidence Caused By Aw Strain In The Lower Rio Grande Valley Of South Texas, Amit Sharma, Teresa Patricia Feria-Arroyo, George Yanev, Madhurababu Kunta

School of Integrative Biological & Chemical Sciences Faculty Publications

Citrus canker, caused by bacterium Xanthomonas citri subsp. citri (Xcc), affects the citrus industry by making the fruit unmarketable due to unsightly lesions on the fruit. Citrus canker caused by a relatively new AWstrain of Xcc was reported on the citrus trees in the residential areas of the Lower Rio Grande Valley (LRGV) of South Texas. Xcc AW has a limited host range, predominantly affecting limes and a few other citrus species. Previous work has reported prevailing environmental conditions that influence the incidence and spread of the citrus canker caused by the Asiatic A strain. However, no information is available …

Leptinotarsa Texana Schaeffer And Gargaphia Arizonica Drake & Carvalho As Potential Biocontrol Agents For The Noxious Weed Solanum Elaeagnifolium Cav, Samikshya Subedi, Stephanie L. Kasper, Alexis Racelis, Greg Lefoe, Rupesh R. Kariyat

School of Earth, Environmental, & Marine Sciences Faculty Publications

Silverleaf nightshade (Solanum elaeagnifolium Cav.; SLN) is a perennial forb native to the southern United States, Mexico and South America that has become a serious agricultural weed across the world. Biological control has emerged as a significant alternative for the management of (SLN) due to the challenges and high costs associated with chemical and mechanical controls. In this study, we used a combination of field and laboratory studies to (1) explore the fundamental and realized host ranges of two North American insects, Leptinotarsa texana Schaeffer and Gargaphia arizonica Drake & Carvalho and (2) assess their suitability as potential biological …

Characterizing The Germination Process And Establishing Best Practices For Seed Propagation Of Tamaulipan Thornscrub Species For Habitat Restoration, Saroj Dhakal

Theses and Dissertations

Tamaulipan thornscrub is an imperiled plant community of southern Texas and northeastern Mexico. Given its importance for biodiversity conservation, stakeholders have been involved in restoration programs using seedlings grown from wild seeds. However, stakeholders often report that insufficient seedling supply is a challenge. To address knowledge gaps in seed germination behavior limiting seedling production, this study was conducted on 18 Tamaulipan thornscrub species, identified by growers as difficult to germinate. Seeds of all studied species are orthodox except Amyris texana, which have recalcitrant properties. Nine species have physical dormancy that was successfully addressed with mechanical and/or chemical scarification. Other species …

Collective Agency And Community Resilience Among Farmworkers In The Lower Rio Grande Valley, Angel Velazquez

Theses and Dissertations

This research assesses how farmworkers in the Lower Rio Grande Valley of Texas use everyday practices to build resilience and adapt to changes in their lives. I apply two interconnected theories, White’s (2017, 2019) framework of collective agency and community resilience and Castro and Sen’s (2022) framework of everyday adaptation actions, to study these practices. I conducted 19 semi-structured interviews with Latino farmworkers and professionals who work with local farmworker organizations in the Rio Grande Valley (RGV) of Texas. Interview transcripts were analyzed to determine if and how Latino farmworkers in the RGV can work towards community resilience and implement …

Determination Of An Effective Natural Boxelder Bug (Boisea Trivittata) Repellent, Reyna Chavez

Theses and Dissertations

This study investigates the use of ecofriendly repellant alternatives to pest management to control boxelder bugs (Boisea trivittata). This bug gathers by the thousands on warm surfaces of exterior suburban homes during early fall and late spring. I determined bug repellency to turmeric oil (Curcuma longa), catnip (Nepeta cataria), citronella (Cymbopogon nardus), and lavender (Lavandula angustifolia). The treatments consisted of essential oils containing 20% methanol. All treatments demonstrated repellency of Boxelder bugs. Citronella was the most effective and had the highest level of repellency range of 90-99%. Catnip was the least effective with a repellency range of 63-82%.

Ecophysiological Benefits Of Industrial Organic Wastes On Alfalfa Yield And Stress Mitigation In Saline Soils, Shugao Fan, Zhuanzhuan Ma, Jiawei Wu, Tianhui Yang, Jincheng Hao, Shumei Chen, Xutong Hu, Ying Zhao

School of Mathematical & Statistical Sciences Faculty Publications

Rising soil salinity and water scarcity demand sustainable solutions to maintain crop productivity. This study evaluated four agro-industrial organic amendments—fish emulsion, neem cake, coffee grounds, and seaweed extract on alfalfa (Medicago sativa) under combined salinity and drought stress, assessing their effects on soil respiration, plant physiology, and yield. Soil CO₂ efflux varied significantly among treatments: coffee grounds induced the highest microbial activity (6.2 μmol m⁻² s⁻¹), suggesting rapid decomposition, while neem cake exhibited stable emissions (3.8 μmol m⁻² s⁻¹), indicating slower organic matter turnover. Fish emulsion showed intermediate dynamics, peaking at 4.8 μmol m⁻² s⁻¹ by week 4, …

Factors Influencing Plant Community Structure And Composition Of Restored Tamaulipan Thornscrub Forests, Jerald T. Garrett, Audrey J. Hicks, Christopher A. Gabler

School of Earth, Environmental, & Marine Sciences Faculty Publications

The Lower Rio Grande Valley (LRGV) of Texas is a biodiversity hotspot due to its high alpha, beta, and gamma diversity and high regional endemism, which are at high risk of degradation. The region has lost 95% of its native thornforest habitat primarily due to agricultural and urban expansion. This study aims to evaluate the current vegetative structure and composition of restored thornforest sites located in the LRGV to identify restoration methods and site characteristics that affect forest restoration outcomes. Twelve restored thornforest sites were selected for this study that varied in time since restoration, patch size, degree of isolation, …

Efficacy Of Lactobacillus Rhamnosus And Its Metabolites To Mitigate The Risk Of Foodborne Pathogens In Hydroponic Nutrient Solution, Esther Oginni, Robin A. Choudhury, Veerachandra Yemmireddy

School of Earth, Environmental, & Marine Sciences Faculty Publications

Hydroponic nutrient solution (HNS) has been established as an ideal conduit for pathogen contamination and proliferation. This study evaluated the efficacy of lactic acid bacteria and their metabolites in mitigating the risk of foodborne pathogens in HNS when compared to conventional chemical treatments. Hoagland’s HNS were prepared according to the manufacturer’s instructions and inoculated with Salmonella Typhimurium, Escherichia coli 0157:H7, and Listeria innocua at 105 CFU/mL cell concentration. These nutrient solutions were subjected to treatment with various concentrations of Lactobacillus rhamnosus live cells, a cell-free extract (CFE) of L. rhamnosus metabolites, sodium hypochlorite and peroxyacetic acid at 22 ± 1 …

Exploring Transcriptional Stress Responses In Sorghum And Evolutionary Insights Into Yth Domain Proteins Across Plants, Shikha Bharti

Theses and Dissertations

Understanding how plants respond to abiotic stress is crucial for enhancing crop resilience in the face of climate change. This thesis explores plant stress adaptation mechanisms through two interlinked studies that address different aspects of gene regulation. The first study investigates the transcriptional dynamics of Sorghum bicolor under drought and heat stress at 1-hour and 6-hour time points. By employing 3'-end RNA sequencing, this study provides a comprehensive temporal view of gene expression changes, revealing stress-responsive transcription factors, hormone-associated pathways, and chromatin regulators. The comparative analysis highlights both common and distinct molecular responses between drought and heat stress, providing insights …

Impact Of Seed Moisture And Temperature On Hemp Seed Germination, Paul Cockson, Andrea Webb, Natalia Martinez-Ochoa, Lindsey Moffitt, Robert Pearce, Manohar Chakrabarti

School of Integrative Biological & Chemical Sciences Faculty Publications

Germination rates of commercial lots of hemp have been highly variable, resulting in poor stand establishment. Germination rates in some seed lots have decreased by 50% after only 1 year of storage. The objective of this trial was to investigate the impact of seed storage conditions on seed germination over time. Industrial hemp (IH) seeds (cv. NWG2730) were harvested from the field. The seeds were cleaned, sorted, and dried to specific moisture contents (MC) 6%, 8%, 10%, and 14%. Seeds were subdivided, placed in hermetically sealed packets, and stored at temperatures of −20°C, 4°C, 10°C, or 21°C for 3, 6, …

Cover Crop-Induced Improvements To Soil Hydraulic Properties And The Role Of Termination Time In Mitigating Negative Soil Moisture Impacts, Fabrizio Javier Pilco

Theses and Dissertations

In the Lower Rio Grande Valley of South Texas, water scarcity and drought pose ongoing challenges for farmers. Although cover crops are promoted for improving soil health and moisture, their effects on soil hydraulic properties in this region remain understudied. This thesis addresses both long-term (Chapter 2) and short-term (Chapter 3) impacts of cover crops on soil hydraulic properties and soil moisture. Long-term effects were evaluated through a three-year participatory field trial across four farms using a BACI design, while short terms were evaluated using a complete randomized block design. Soil hydraulic properties (residual water content θr, saturated water content …

Climate Resilience In Texas Assessing The Impact Of Extreme Weather On Energy Poverty And The Mitigating Role Of Tree Canopy Coverage, Yongwen Yang

Theses and Dissertations

Extreme weather events, including severe heat and cold waves —increasingly threaten public health, economic stability, and energy equity. This two-part study examines the interplay between extreme weather, energy poverty, and green infrastructure (tree canopy coverage) in Texas, a state characterized by climatic extremes and socioeconomic diversity.

This study consists of four chapters. The first chapter in the Introduction includes the research background, existing research, research gaps, research questions, and potential contributions. Followed by two core chapters. Chapter II aims to assess the impact of extreme weather on energy poverty at the household level. Chapter III aims to identify whether tree …

Survival, Biofilm Formation, And Control Of Foodborne Pathogens In Hydroponic Systems, Sai Rithin Reddy Kothur Thirupathi

Theses and Dissertations

The growing global population and increasingly unpredictable weather patterns have intensified the demand for sustainable food production methods. Hydroponics, a form of Controlled Environment Agriculture (CEA), has gained attention as a viable solution due to its efficient use of resources such as land and water. Although hydroponic systems are perceived as safer alternatives to conventional farming, recent foodborne outbreaks associated with these systems have raised significant public health concerns. This thesis research investigated the food safety risk in hydroponic, particularly the survival and persistence of foodborne pathogens. Chapters I and II provide a comprehensive overview of hydroponics and the microbial …

Climate Change And The Field Of Farm Labor In The Lower Rio Grande Valley, Texas, Cody Richard Mortell

Theses and Dissertations

Farm workers in the United States are often vulnerable to adverse impacts of climate change, particularly extreme heat. This study explores farm workers’ climate change perceptions (CCP) as a mediating force in climate adaptation. Using latent class analysis, in-person survey data (n=404) from Lower Rio Grande Valley, TX (2024) and NOAA data were analyzed. Results were interpreted using Bourdieu’s field analysis framework and his notions of capital and symbolic power. Findings include: a social hierarchy with three latent classes of workers based on economic, cultural, social, and symbolic capital, which statistically significantly affected CCP. Workers in higher structural positions were …

Meta-Transcriptomes Of The Microbial Communities Of The Different Developmental Life Stages Of Anastrepha Ludens (Diptera: Tephritidae), Erin L. Schuenzel

School of Integrative Biological & Chemical Sciences Faculty Publications

The Mexican fruit fly, Anastrepha ludens, is a polyphagous pest that is a constant threat to US agriculture because of its proximity to citrus production in border region of the United States and Mexico. Sterile Insect Technique has been used to manage and eradicate of the Mexican Fruit Fly. SIT, however, requires millions of sterile male flies to be released each week from mass-rearing facilities. The mass-reared colonies must deal with microbial infections that reduce survivorship, fecundity and male-male competition. Meta-transcriptomics joins culturing and next generation DNA sequencing techniques to understand these changing microbial communities. This study uses advances …

Efficiency Of Labor In Winter Pruning Of Apple Trees Using Technological Innovations, Élio Fillipi Dos Santos, Wendel Paulo Silvestre, Lessandra Silva Rodrigues, Carine Cocco

School of Earth, Environmental, & Marine Sciences Faculty Publications

The increase of new technologies in fruit-growing crops has increased productivity in cultural practices and helped farmers expand their production areas. This work aimed to quantify labor performance in winter pruning of apple trees, using manual and electronic scissors associated with utilizing a pruning platform and ladders. The treatments consisted of two types of pruning shears and two support systems. A pruner carried out pruning for 16 days, with a journey of 10 h per day. The average yield in manual pruning with a ladder was 21.35 plants pruned per hour per man. Using a platform, the yield increased to …

Can Trichoderma Spp. Contribute To The Bioremediation And Biostimulation Of Plants In Soil Contaminated With Herbicides?, Elaine Damiani Conte, Elton José Da Rosa, Gabriel Rieth Silvestrini, Daiane Da Silva Motta, Christiane Fernandes De Oliveira, Carine Cocco, Gabriel Fernandes Pauletti, Taísa Dal Magro, Joséli Schwambach

School of Earth, Environmental, & Marine Sciences Faculty Publications

This work aimed to evaluate the potential of Trichoderma spp. in the bioremediation of herbicides and biostimulation of plants in herbicide-contaminated soils. In the first phase, the experiment followed a completely randomized design in a 4 × 3 × 4 factorial scheme with five replications, four strains of Trichoderma spp., three herbicides, and four herbicide doses. The mycelial growth speed index (MGSI) of Trichoderma spp. was obtained by growing it in a Petri dish with PDA associated with different doses of herbicides and evaluated every 24 h for 10 days. Results indicated the selection ofTrichoderma harzianumT1A to continue …

Pathogen And Host Associations Of Soft Ticks Collected In South Texas, Sarah E. Mays Maestas, Lauren P. Maestas, Phillip E. Kaufman

School of Integrative Biological & Chemical Sciences Faculty Publications

Background: Soft ticks (Family: Argasidae) are vectors of relapsing fever Borrelia in the United States and are potential vectors of African swine fever virus, a pathogen that could have a devastating effect on the U.S. swine industry if introduced to the U.S. mainland. Much of the tick-borne disease research in the U.S. focuses on hard ticks, and less is known about the ecology of soft ticks. Some soft tick species found in the southern U.S. have a wide host range and may feed on cattle, swine, native and exotic ungulates, small mammals, reptiles, and humans. Because the feeding habit of …

Intraspecific Variability Of Rice Root Knot Nematodes Across Diverse Agroecosystems For Sustainable Management, Sandip Mondal, Arnab Purohit, Anjan Hazra, Sampa Das, Manohar Chakrabarti, Matiyar Rahaman Khan, Horacio Lopez-Nicora, Dipankar Chakraborti, Abhishek Mukherjee

School of Integrative Biological & Chemical Sciences Faculty Publications

In the rice agroecosystems of Southeast Asia, rice root knot nematode (Meloidogyne graminicola) significantly impairs yield, representing a major species within the ‘graminis-group’ known for its morphological similarities with other root knot nematodes (RKNs). This study delves into the variations in reproductive potential, morphology, morphometrics, and genetic diversity among thirty RKN populations in rice across three distinct agroecological zones in Jharkhand, India. Despite notable differences in reproductive potential among the populations, morphological and morphometric correlations to reproductive potential were inconclusive. However, male and juvenile morphometrics were crucial for identifying intraspecific variability. Genetic analysis utilizing five molecular markers (ITS, …

Guiding Wildlife: Evaluating Wildlife Exit Designs And Sensor Lights For Safer Highways In South Texas, Rupesh Maharjan

Theses and Dissertations

Roadside exclusionary fencing is more prevalent on highways to prevent wildlife-vehicle collisions. Although it can mitigate wildlife road mortality by limiting their access to the road, it can also create a barrier for wildlife stranded within the right-of-way. In State Highway 100 of Texas, the Texas Department of Transportation installed ten wildlife exits to allow wildlife to escape the fenced roadway, and a pair of sensor lights on 13 wildlife guards (WGs) to scare off target species (bobcats and coyotes) from crossing the guards and accessing the roadway. In this study, the effectiveness of three wildlife exit (WE) designs were …

Implementing Organic Fertilization Practices To Improve Aloe Vera Growth And Soil Health In The Lower Rio Grande Valley, Isaiah Edward Jaramillo

Theses and Dissertations

Aloe vera (L.) (Aloe) Burm. f., is valued for its applications across the cosmetic, medicinal, and food industries due to its leaf gel. In the aloe industry, the extraction of gel from leaves generates significant quantities of organic waste, which presents an opportunity to repurpose this material as an amendment in aloe cultivation. While Aloe is renowned for its resilience, understanding the feasibility of using these organic shavings as a soil fertility amendment in aloe production is critical. This research aims to identify sustainable fertilization methods for Aloe that can maintain and/or improve crop yield while enhancing soil health. This …

Examining Hispanic Beginning Farmers And Ranchers In The Rio Grande Valley Through A Community Capitals Framework, Perla Kimberly Schrock

Theses and Dissertations

While existing literature addresses the experiences of beginning farmers and ranchers (BFR), there is a notable gap in research focused on Hispanic beginning farmers and ranchers (HBFR). This study aimed at exploring the unique experiences of HBFR in a predominantly Hispanic region, the Rio Grande Valley (RGV), employed the Community Capitals Framework (Flora et al., 2016). I conducted 16 semi-structured interviews with HBFR and local nonprofit organizations and federal employees, complemented by participant observations. Through thematic and content analysis of the interview transcripts, findings revealed valuable insights into the livelihoods of HBFR. Despite HBFR facing significant challenges, this study demonstrated …

Assessing Cover Crop Adoption Factors In The Rio Grande Valley Through A Social-Ecological Perspective, Mackenzie Feldman

Theses and Dissertations

Reducing agriculture’s negative environmental impacts is crucial for mitigating climate change (White, 2021). Cover crops– non-cash crops grown to benefit subsequent cash crops– can slow erosion, improve soil health, enhance water availability, control pests, and increase biodiversity. Despite these benefits, adoption rates remain low, prompting the USDA and other organizations to fund research on increasing their use. Most studies focus on the Midwest and Northeast, and emphasize individual factors over the relationship between structural factors and individual factors that impact farmers’ decisions to adopt cover crops. This USDA-funded study begins to fill this gap by exploring social-ecological factors and how …

A New Record Of Fleas From Nilgai Antelope In Southern Texas And Fleas From Other Wildlife, Sarah E. Mays Maestas, Jason Tidwell, John A. Goolsby, Lauren P. Maestas

School of Integrative Biological & Chemical Sciences Faculty Publications

Wildlife are hosts of ectoparasites, such as fleas and ticks that may transmit human and animal pathogens. Little is known about the ecology of many ectoparasite species native to southern Texas, or their role in pathogen maintenance and transmission. Much attention has been given to the role of nonnative nilgai antelope as cattle fever tick hosts and agents of dispersal, but little attention has been given to other ectoparasites that may utilize nilgai antelope as hosts. As southern Texas is a hot-spot for flea-borne (murine) typhus, it is important to examine flea species presence, abundance, and host use in this …