Biology Commons^™

The Molecular Evolution Of Insect Opsin Genes, Maria Jose Cardenas Muedano

Theses and Dissertations

Opsins are part of the superfamily of G-coupled receptor proteins and together with chromophores, are responsible for initiating the signal transduction cascade responsible for animal vision. Since opsins have a critical role on visual perception these genes are crucial for a myriad of adaptive traits and behaviors and should show diverse signs of natural selection at the molecular level. Understanding the evolution of opsins across the wide diversity of insect groups will allow us to better understand the evolutionary pressure on insect opsins and serve as a model for both other gene systems and other taxonomic groups of animals that …

Foxo Factors Regulate The Expression Of Canonical Wnt Target Genes In A Set Of Basal-Like Breast And Glioblastoma Multiforme Cancer Cell Lines, Shania Pintor

Theses and Dissertations

Basal-like breast cancer (BBC) and Glioblastoma Multiforme (GBM) each express stem gene expression signatures which are partly driven by FOXO transcription factors. Preliminary data from Gene Set Enrichment Analysis (GSEA) with RNA Seq. data indicated that a set of WNT target genes including LEF1, and TCF7 were robustly induced after 48-hours of AS1842856 (FOXO1 inhibitor) treatment. These same genes were also induced in GBM cell lines U87MG, LN18, LN229, A172, and DBTRG upon treatment with AS1842856. In contrast to FOXO1 inhibition, RNAi targeting of FOXO1, led to reduced LEF1, and TCF7 gene expression in BT549 and U87MG …

Effects Of Disturbance (Mowing) On Florivory And Floral Defenses In Solanum Elaeagnifolium, A Noxious And Worldwide Invasive Weed, Alejandro Rafael Vasquez Marcano

Theses and Dissertations

Chapter 1: Literature Review- In this literature review we have examined weed management as it concerns urban and agricultural ecosystems, as well as the need for mowing assessments as it relates to floral traits and defense against herbivory.

Chapter 2: Experiments- In the experiments we examined the role of mowing on floral growth traits, floral defense traits, and their effect on Manduca sexta specialist herbivores.

Chapter 3: Results- In the results we found SLN flowers to have larger diameters than unmowed flowers; however, flower mass was in line with our predictions as unmowed flowers were heavier in high mowing frequency …

Wildlife Road Mortality Patterns In South Texas And Survey Methodology Improvement, Bradley E. Beer

Theses and Dissertations

Mortalities of wildlife caused by collisions with vehicles along roads are increasing in prevalence, threatening the existence of various species and populations. A better understanding of how mortalities change in response to natural and anthropogenic variables and efficient methods of obtaining mortality data are essential to mitigating such mortalities. This thesis investigates several key elements to improving road mortality surveys in south Texas. First, it was found that road mortality survey counts did not change under a pandemic-related lockdown and that 2 mortality survey observers detect more mortalities than 1. Analysis of brown pelican groundings on Texas State Highway 48 …

Population Density And Reproductive Seasonality Of Tryonia Cheatumi (Gastropoda: Cochliopidae), The Phantom Tryonia, Kathryn E. Perez, Nina Noreika, Chad Norris, Marty Kelly, Melissa Lopez, Christina Ortega, Salma Ruiz Sandoval, Samantha Gonzalez, Weston Nowlin

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

We studied population density, population size, and reproductive seasonality of the Phantom Tryonia, Tryonia cheatumi (Pilsbry, 1935). This endangered freshwater snail is found only in the San Solomon Spring system, a cienega, or karst-based, arid-land freshwater spring system, in western Texas, USA. We sampled populations at seven locations in the system seasonally over a 2-yr period. San Solomon Spring, the system's largest spring and modified into a swimming pool, had the largest population of T. cheatumi, with an estimated 49 million individuals and a mean density as high as 23,626 ± 39,030 (individuals/m2 ± SD). There were seasonal differences …

Soil Nematode Trophic Group Composition And Influence On Growth Of Amaranthus Palmeri And Parthenium Hysterophorus, Orlando Garcia, Dana Garibaldi, Krissa Jhaveri, Jake Lanoue, Pushpa G. Soti

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Weeds have a significant impact on agricultural systems. They not only cause a loss in crop yield by competing with them for resources, but they can also serve hosts for several pests and parasties such as plant parasitic nematodes casusing additional crop loss. The aim of this study was to analyze plant-nematode feedback in two major weeds, Amaranthus palmeri S Watson and Parthenium hysterophorus L. First, a field survey was conducted to determine the rhizosphere nematode trophic groups associated with these two plants in the summer of 2020 and 2021. Then a 6-week greenhouse study was conducted where the two …

Mechanistic Insight Into Functionally Different Human Islet Polypeptide (Hiapp) Amyloid: The Intrinsic Role Of The C-Terminal Structural Motifs, Dibakar Sarkar, Narayan Chandra Maity, Gourav Shome, Kyriakos Gabriel Varnava, Vijayalekshmi Sarojini, Subramanian Vivekanandan, Nirakar Sahoo, Sourav Kumar, Atin Kumar Mandal, Ranjit Biswas, Anirban Bhunia

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Targeting amyloidosis requires high-resolution insight into the underlying mechanisms of amyloid aggregation. The sequence-specific intrinsic properties of a peptide or protein largely govern the amyloidogenic propensity. Thus, it is essential to delineate the structural motifs that define the subsequent downstream amyloidogenic cascade of events. Additionally, it is important to understand the role played by extrinsic factors, such as temperature or sample agitation, in modulating the overall energy barrier that prompts divergent nucleation events. Consequently, these changes can affect the fibrillation kinetics, resulting in structurally and functionally distinct amyloidogenic conformers associated with disease pathogenesis. Here, we have focused on human Islet …

Low Soil Nitrogen And Moisture Limit The Expansion Of The Invasive Grass, Megathyrsus Maximus (Guinea Grass) In Semi-Arid Soils, E. Penelope Holland, Vanessa Thomas, Pushpa G. Soti

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

The goal of this study was to predict the range expansion potential of an invasive forage grass, Guinea grass (Megathyrsus maximus). We collected rhizosphere soil samples of M. maximus and coexisting species from 150 different locations and analysed them for soil properties. We estimated the probability of M. maximus presence as a function of soil moisture, organic matter, pH, salinity, total N, and CN ratio using logistic regression. Presence of M. maximus was associated with higher soil moisture, higher organic matter, pH, and nitrogen, but lower salinity and CN ratio. Soil nitrogen and moisture …

Intracellular Hemin Is A Potent Inhibitor Of The Voltage-Gated Potassium Channel Kv10.1, Nirakar Sahoo, Kefan Yang, Alisa Bernert, Sandip M. Swain, Guido Gessner, Reinhard Kappl, Toni Kühl, Diana Imhof, Toshinori Hoshi, Roland Schönherr, Stefan H. Heinemann

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Heme, an iron-protoporphyrin IX complex, is a cofactor bound to various hemoproteins and supports a broad range of functions, such as electron transfer, oxygen transport, signal transduction, and drug metabolism. In recent years, there has been a growing recognition of heme as a non-genomic modulator of ion channel functions. Here, we show that intracellular free heme and hemin modulate human ether à go-go (hEAG1, Kv10.1) voltage-gated potassium channels. Application of hemin to the intracellular side potently inhibits Kv10.1 channels with an IC50 of about 4 nM under ambient and 63 nM under reducing conditions in a weakly voltage-dependent manner, …

Analysis Of Sanitizer Rotation On The Susceptibility, Biofilm Forming Ability And Caco-2 Cell Adhesion And Invasion Of Listeria, Md Asfakur Rahman, Nirakar Sahoo, Veerachandra K. Yemmireddy

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

The purpose of this study was to determine the effect of sanitizer use conditions on the susceptibility, biofilm forming ability and pathogenicity of Listeria monocytogenes. Two different strains of L. monocytogenes and a non-pathogenic L. innocua were exposed to sodium hypochlorite, benzalkonium chloride and peroxyacetic acid at different concentrations (4 to 512 ppm) and treatment times (30 s to 5 min), respectively. Under the tested conditions, no significant difference (p > 0.05) in reduction was observed among the three tested sanitizers. A reduction of 1 to 8 log CFU/mL was observed depending upon the sanitizer concentration and treatment times. The survived …

Cytochrome C: A Potential Early Biomarker Of Diabetic Retinopathy, Ileana G. Villarreal

Theses and Dissertations

Diabetic retinopathy is an ocular disease which appears in patients who experience progression of diabetes mellitus over a continuous period. Oftentimes, patients go undiagnosed due to the fact that there is no way to determine when the exact moment a patient develops diabetic retinopathy. Ophthalmologists and other eye specialists diagnose a patient with diabetic retinopathy once the patient begins to show progressed symptoms of the disease. Various experiments have been previously performed to increase our knowledge of the connection of diabetic retinopathy and early biomarkers of the disease. Several studies have determined the effects of diabetic retinopathy and apoptosis with …

De Novo Transcriptome Analysis Of Orange Jasmine (Murraya Paniculata) Infected With Citrus Greening Disease, Jeffrey Aquino Gomez

Theses and Dissertations

Citrus greening disease, also known as Huanglongbing, is one of the most devastating citrus diseases in the world. Candidatus Liberibacter asiaticus (CLas) is a non-culturable, phloem-limited bacterium that serves as one of two vectors for the transmission of any of the three kinds of greening disease. In cooler climates, the African variant transmitted by the African citrus psyllid (Trioza erytreae) is more prevalent. The Asian form transmitted by the Asian citrus psyllid (Diaphorina citri) where is predominant in warmer conditions and recently discover the American form who is also transmit by Diaphorina citri, was discover in Brazil but has also …

Examination Of Amphibian Community And Environmental Relationships In South Texas Using Environmental Dna (Edna), Sean Michael Collins

Theses and Dissertations

Developing more efficient tools to assess amphibian biodiversity and understanding what environmental variables drive amphibian biodiversity are top priorities, as amphibians are facing extinction events across the globe. Environmental DNA (eDNA) surveys are a promising new tool to asses amphibian biodiversity. Throughout the study eDNA metabarcoding along with a targeted eDNA assay and traditional survey methods were used to provide foundational information on amphibian community assemblages throughout South Texas. Water quality, habitat characteristics and soil composition data were collected and used to examine environmental relationships. eDNA metabarcoding detected significantly more amphibian taxonomic units compared to traditional survey …

Biological Flora Of Coastal Wetlands: Sporobolus Cynosuroides (L.) P.M. Peterson & Saarela, Richard Stalter, Robert I. Lonard

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Sporobolus cynosuroides (L.) P.M. Peterson & Saarela¼Spartina cynosuroides (L.) Roth is a temperate zone rhizomatous grass that often is a dominant species in coastal brackish marshes on the Gulf coast and Atlantic coasts of the United States where salinity ranges from 0 to 10 psu. Sporobolus cynosuroides (L.) P.M. Peterson & Saarela ¼ Spartina cynosuroides (L.) Roth is usually absent where salinity values are .12 psu. Sporobolus cynosuroides occurs in coastal habitats characterized by infrequent tidal flooding and moderate nutrient levels. Also known as big cordgrass, it may account for net productivity in high marshes that rivals productivity of Sporobolus …

A Rationally Designed Synthetic Antimicrobial Peptide Against Pseudomonas-Associated Corneal Keratitis: Structure-Function Correlation, Sk Abdul Mohid, Prerana Sharma, Amani Alghalayini, Tripti Saini, Debarun Datta, Mark D. P. Willcox, Haydar Ali, Sreyan Raha, Achintya Singha, Nirakar Sahoo

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Contact lens wearers are at an increased risk of developing Pseudomonas-associated corneal keratitis, which can lead to a host of serious ocular complications. Despite the use of topical antibiotics, ocular infections remain a major clinical problem, and a strategy to avoid Pseudomonas-associated microbial keratitis is urgently required. The hybrid peptide VR18 (VARGWGRKCPLFGKNKSR) was designed to have enhanced antimicrobial properties in the fight against Pseudomonas-induced microbial keratitis, including contact lens-related keratitis. In this paper, VR18's modes of action against Pseudomonas membranes were shown by live cell Raman spectroscopy, live cell NMR, live-cell fluorescence microscopy and measures taken using sparsely tethered bilayer …

What Are Mycorrhizal Traits?, V. Bala Chaudhary, E. Penelope Holland, Suw Charman-Anderson, Aidee Guzman, Lukas Bell-Dereske, Tanya E. Cheeke, Adriana Corrales, Jessica Duchicela, Cameron Egan, Pushpa G. Soti

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Highlights

• Applying trait-based approaches to ecological research on mycorrhizal symbioses broadens ecological inferences, but there is no single unified framework to unite disparate language, terminology, and methods across the many multidisciplinary scientists studying mycorrhizas.
• We propose an inclusive framework for trait-based mycorrhizal ecology aimed to stimulate scientists around the world to collect and use more mycorrhizal trait data, particularly in understudied areas. This would widen our understanding regarding the ecological role of mycorrhizal symbioses at individual, species, community, and ecosystem scales.
• Analyzing how mycorrhizal symbioses fit within existing trait definitions highlights significant theoretical and empirical knowledge gaps, novel questions, and …

Modeling The Impact Of Climate Change On Cervid Chronic Wasting Disease In Semi-Arid South Texas, Md Rafiul Islam, Ummugul Bulut, Teresa Patricia Feria-Arroyo, Michael G. Tyshenko, Tamer Oraby

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Chronic wasting disease (CWD) is a spongiform encephalopathy disease caused by the transmission of infectious prion agents. CWD is a fatal disease that affects wild and farmed cervids in North America with few cases reported overseas. Social interaction of cervids, feeding practices by wildlife keepers and climate effects on the environmental carrying capacity all can affect CWD transmission in deer. Wildlife deer game hunting is economically important to the semi-arid South Texas region and is affected by climate change. In this paper, we model and investigate the effect of climate change on the spread of CWD using typical climate scenarios. …

Stinging The Predators: A Collection Of Papers That Should Never Have Been Published, Zen Faulkes

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

This ebook collects academic papers and conference abstracts that were meant to be so terrible that nobody in their right mind would publish them. All were submitted to journals and conferences to expose weak or non-existent peer review and other exploitative practices. Each paper has a brief introduction. Short essays round out the collection.

The Potential Impact Of Climate Change On The Distributions Of Eleutherodactylus Cystignathoides And E. Planirostris (Anura: Eleutherodactylidae), Rebecca T. Chastain

Theses and Dissertations

Climate change is inducing changes in the distributions of many species, causing range shifts and habitat loss as well as facilitating invasions. It is a broad contributor to global amphibian decline, already causing mass extinctions and extirpations of amphibian populations, a phenomenon which is expected to continue. The understudied direct-developing frog Eleutherodactylus cystignathoides is a notable outlier, having rapidly expanded its distribution in recent years. This is of particular interest given that other eleutherodactylids, such as E. coqui and E. planirostris, have already shown propensity for rapid dispersal and invasion. Originally found in the southernmost tip of …

Effects Of Tributyltin Exposure On 8-Ohdg And Dsdna Expressions, Oxidative And Nitrative Stress In The American Oyster, Crassostrea Virginica, Mohan Kumar Dash

Theses and Dissertations

Environmental pollution increases due to anthropogenic activities. Different types of pollutants and/or chemicals impair growth, reproduction and development in aquatic organisms. Tributyltin (TBT, an organotin compound) is a tremendously toxic substance which widely uses as antifouling paints used in boats, hulls, and ships. The toxic effect of TBT is well documented in teleost species. The American oyster (Crassostrea virginica) is an ideal shellfish species to study on TBT exposure DNA lesion and oxidative/nitrative stress. In this study, the effects of TBT on 8’-hyrodxy-2’-deoxyguanosine (8-OHdG, a molecular marker), dsDNA, dinitrophenyl protein …

Removal Of Arsenic (Iii) And Arsenic (V) From Aqueous Solution Via Common Sunflower Helianthus Annuus By Phytoremediation, Irving A. Vazquez Hurtado

Theses and Dissertations

Phytoremediation provides a cost-effective, non-invasive technique to remove contaminants from the soil and groundwater. Sunflowers are fast growing and have a showed effective at removing various pollutants from soil, including lead and other heavy metals. Health issues related to arsenic are mainly attributed to exposure of arsenite, whereas arsenate is much less toxic. The common sunflower Helianthus annuus was the species used to remove both arsenic (III) and As(V) ions from hydroponics solutions. In the present study sunflower seeds were germinated for a week, placed under the sun for a day and subsequently placed in a nutrient solution to aid …

Winners And Losers In Dryland Reforestation: Species Survival, Growth, And Recruitment Along A 33-Year Planting Chronosequence, Clifton Albrecht, Zarek Contreras, Kimberly Wahl-Villarreal, Mitch Sternberg, Bradley O. Christoffersen

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Reforestation in the Lower Rio Grande Valley (LRGV) of Texas began in the 1960s and to date over 6,475 ha of land has been reforested. However, there has been minimal assessment to understand differential species success, compositional trends, and the aboveground C sequestration potential of these developing forests. We coupled quantitative planting information of >50 native woody tree and shrub species with surveys of 5,223 stems of 4,606 individuals in a chronosequence of restored forests ranging in age from 1 to 33 years to estimate species-specific mortality rates, biomass accumulation and recruitment, as well as compositional trends in the herbaceous …

Towards Conserving Crop Wild Relatives Along The Texas–Mexico Border: The Case Of Manihot Walkerae, Gisel Garza, Crystian Sadel Venegas Barrera, Jon Dale, José Guadalupe Martínez-Ávalos, Teresa Patricia Feria-Arroyo

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Walker’s Manihot, Manihot walkerae, is an endangered species endemic to south Texas and northeastern Mexico and is a Crop Wild Relative (CWR) of the international and economically important crop cassava (M. esculenta). Manihot walkerae is globally endangered (IUCN’s Redlist, Texas list, USA); however, it is not recognized on the Mexican list of endangered species (NOM-059-SEMARNAT). We assessed the status of M. walkerae in Mexico and re-evaluated its global status. According to our analysis, M. walkerae should be considered an endangered species based on the IUCN’s assessment method and a threatened species in Mexico based on the Mexican criteria. Our findings …

Impact Of Hydrologic Alteration On Brazos River Pelagophilic Minnows, Christopher M. Taylor, Kevin B. Mayes

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

The lower Brazos River has been profoundly altered since the construction of multiple impoundments. The resulting river regulation poses problems for organisms adapted to a natural flow regime and is thought to play a major role in the imperilment of seven native minnows that synchronize spawning during high flow pulses. Four of the species are presumably extirpated from the region, but their declines and losses differed across time. To address potential reasons for species’ declines, we assessed pre- and post-impoundment changes in flow regime from five gaging stations across the lower Brazos River to identify river flow characteristics that depart …

Screening Commercial Entomopathogenic Fungi For The Management Of Diaphorina Citri Populations In The Lower Rio Grande Valley, Texas, Usa, Justin Wendel, Jonathan Cisneros, Stefan Jaronski, Christopher Vitek, Matthew Ciomperlik, Daniel Flores

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Ten strains of entomopathogenic ascomycete fungi, sourced from commercial formulations of blastopore or conidiospore formulations, were tested in 14 different formulations in a primary acquisition/direct spray bioassay against adult Asian citrus psyllid (Diaphorina citri Kuwayama (Hemiptera: Liviidae)). The Cordyceps (Isaria) javanica Apopka 97-C (conidia) strain was used as the standard. A statistical ranking system was established in which top performing pathogenic strains were selected for further screening and eventual field trials. Modified Potter-type spray towers were utilized to deliver a range of doses of viable spores to adult D. citri in an aqueous spray consistent with …

Cover Crops May Exacerbate Moisture Limitations On South Texas Dryland Farms, Stephanie Kasper, Faeqa Mohsin, Lindsey Richards, Alexis Racelis

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Cover crops are a sustainable management tool for mediating weed pressure, reducing soil erosion, and enhancing soil organic carbon (C) and nitrogen (N) levels. Yet, adoption rates across water-limited farms in Texas remain low, especially among producers without irrigation access, due to concerns that cover crop use of soil moisture will negatively impact subsequent cash crop yields. This three-year cover crop trial in a rain-fed sorghum (Sorghum bicolor L.) farm in Lyford, Texas, trialed different cover crop mixes and seeding rates and confirmed that cover cropping leads to significant soil moisture deficits and cash crop failure when rainfall is low …

Diel Activity Patterns Of Two Distinct Populations Of Aedes Aegypti In Miami, Fl And Brownsville, Tx, John-Paul Mutebi, André Barretto Bruno Wilke, Erik Ostrum, Chalmers Vasquez, Gabriel Cardenas, Augusto Carvajal, Maday Moreno, William D. Petrie, Arturo Rodriguez, Henry Presas, Jesus Rodriguez, Fred Barnes, Christopher Vitek, Xochitl Estrada, Thalia Rios, Jeremy Marshall

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

The diel biting activity of Aedes (Stegomyia) aegypti (L) populations was extensively investigated in the early 1900s to gain more information on the biology of Ae. aegypti, and this information was used to devise effective approaches to controlling populations of this species and protect the human population from widespread arbovirus outbreaks. However, few contemporary studies are available regarding the diel activity patterns of Ae. aegypti. To assess the diel activity patterns of Ae. aegypti in southern Florida and Texas, we conducted 96-h uninterrupted mosquito collections once each month from May through November 2019 in Miami, Florida, and Brownsville, Texas, using …

Insecticide Resistance In Aedes Aegypti Varies Seasonally And Geographically In Texas/Mexico Border Cities, Heather Hernandez, Flor A. Martinez, Christopher Vitek

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Insecticide use is the primary method of attempting to reduce or control the spread of mosquito-borne diseases. Insecticide resistance is a major concern as resistance will limit the efficacy of vector-control efforts. The lower Rio Grande Valley region of South Texas has had autochthonous transmission of multiple mosquito-borne diseases including those caused by dengue virus, chikungunya virus, and Zika virus. However, the current status of mosquito resistance to commonly used pesticides in this region is unknown. In this study, we collected field samples from multiple municipalities in South Texas and assessed resistance using the Centers for Disease Control and Prevention …

Assessment Of Two Novel Host-Derived Beauveria Bassiana (Hypocreales: Cordycipitaceae) Isolates Against The Citrus Pest, Diaphorina Citri (Hemiptera: Liviidae), Jonathan Cisneros, Justin Wendel, Stefan Jaronski, Christopher Vitek, Matthew Ciomperlik, Daniel Flores

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

The Asian citrus psyllid (ACP), Diaphorina citri Kuwayama (Hemiptera: Liviidae), vectors ‘Candidatus Liberibacter spp.’, the causative agent of Citrus Greening Disease (CGD) or Huanglongbing (HLB). Managing populations of psyllids in the Lower Rio Grande Valley (LRGV), TX, United States is imperative given a continuous increase in HLB-positive trees. A component of integrated pest management (IPM) program is the use of strains of entomopathogenic fungi for the biological control of D. citri. In an attempt to find endemic strains of entomopathogenic fungi that grow favorably under LRGV environmental conditions and naturally infect D. citri, psyllids were collected from …

Review Of The Invasive Forage Grass, Guinea Grass (Megathyrsus Maximus): Ecology And Potential Impacts In Arid And Semi-Arid Regions, Pushpa Soti, Vanessa Thomas

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Several introduced African grasses are known to present recurring patterns of invasiveness and cause a severe impact on the diversity and functioning of ecosystems worldwide. Megathyrsus maximus (Guinea grass), a forage grass species native to South Africa, is reported to be highly invasive and pose a serious threat to native biodiversity in the introduced range. Despite the severe ecological threats posed by M. maximus worldwide, there is a dearth of information on the ecological and agroecological impact of M. maximus when growing in unintended areas. In this review, we present general information on M. maximus, its distribution and ecological …