Life Sciences Commons^™

Stimulation Of Ammonia Oxidizer And Denitrifier Abundances By Nitrogen Loading: Poor Predictability For Increased Soil N2o Emission, Yong Zhang, Feng Zhang, Diego Abalos, Yiqi Luo, Dafeng Hui, Bruce A. Hungate, Pablo García-Palacios, Yakov Kuzyakov, Jørgen Eivind Olesen, Uffe Jørgensen, Ji Chen

Biology Faculty Research

Unprecedented nitrogen (N) inputs into terrestrial ecosystems have profoundly altered soil N cycling. Ammonia oxidizers and denitrifiers are the main producers of nitrous oxide (N₂O), but it remains unclear how ammonia oxidizer and denitrifier abundances will respond to N loading and whether their responses can predict N-induced changes in soil N₂O emission. By synthesizing 101 field studies worldwide, we showed that N loading significantly increased ammonia oxidizer abundance by 107% and denitrifier abundance by 45%. The increases in both ammonia oxidizer and denitrifier abundances were primarily explained by N loading form, and more specifically, organic N …

Bases For The Establishment Of Robusta Coffee (Coffea Canephora) As A New Crop For Colombia, Luis F. Campuzano-Duque, Juan Carlos Herrera, Claire Ged, Matthew Wohlgemuth Blair

Agricultural and Environmental Sciences Faculty Research

Robusta coffee (C. canephora) covers 36% of world coffee production and has strategic relevance as a beverage that it is produced by thousands of small-scale producers around the world. Although mainly grown in Africa and Asia as opposed to Latin America, this situation is changing. Colombia is recognized as a producer of high-quality Arabica (C. arabica L.) coffee, however we argue that Robusta represents a great economic opportunity for small scale producers, for the industrialization of new products and for emerging coffee chains. Therefore, the objective of this review is to outline the agronomic value of Robusta coffee as a …

Citric Acid/Β-Alanine Carbon Dots As A Novel Tool For Delivery Of Plasmid Dna Into E. Coli Cells, Anju Pandey, Asmita Devkota, Anil Sigdel, Zeinab Yadegari, C. Korsi Dumenyo, Ali Taheri

Agricultural and Environmental Sciences Faculty Research

Successful delivery of plasmid DNA into the microbial cells is fundamental in recombinant DNA technology. Natural bacterial transformation is limited to only certain species due in part to the repulsive forces between negatively charged DNA and bacterial membranes. Most common method of DNA delivery into bacteria is artificial transformation through heat shock and electroporation. These methods require sophisticated instruments and tedious steps in preparation of competent cells. Transformation by conjugation is also not applicable to all plasmids. Nanoparticles have been used successfully in therapeutics for drug delivery into animal cells. They are starting to gain popularity in plant sciences as …

Antibiotic Resistant Enterobacteriaceae In Milk Alternatives, Winnie Mukuna, Abdullah Ibn Mafiz, Bharat Pokharel, Aniume Tobenna, Agnes Kilonzo-Nthenge

Human Sciences Faculty Research

The consumption of non-dairy milk is on the rise due to health benefits. Although there is increasing inclination towards milk alternatives (MA), there is limited data on antibiotic resistant bacteria in these substitutes. The aim of this study was to investigate antimicrobial resistance of bacteria isolated from MA. A total of 138 extracts from almonds (n = 63), cashew nuts (n = 36), and soybeans (n = 39) were analyzed for Enterobacteriaceae. The identification of the bacteria was based on biochemical and PCR methods. Antibiotic sensitivity was determined by using the Kirby-Bauer disk diffusion technique. Overall, 31% (43 of 138) …

Identification And Management Of Phytophthora Aerial Blight Caused By Phytophthora Nicotianae On Catharanthus Roseus, Fulya Baysal-Gurel, Ravi Bika, Terri Simmons, Farhat A. Avin

Agricultural and Environmental Sciences Faculty Research

Phytophthora nicotianae is the most common pathogen in nurseries and gardens, infecting both woody and herbaceous ornamental plants. Phytophthora aerial blight symptoms such dull water-soaked lesions on shoot tips and leaf petioles, girdling on the main stem, necrosis, and wilting of annual vinca were observed in a commercial greenhouse in Warren Co., Tennessee, USA in May 2016. The objective of this study was to identify the causal agent of Phytophthora aerial blight and develop a fungicide management recommendation for ornamental producers. Attempts to isolate the pathogen from symptomatic leaf tissue were conducted and excised leaf pieces were embedded in the …

Comparative Study Of Sensory Attributes Of Leafy Green Vegetables Grown Under Organic And Conventional Management, Kripa Dhakal, Ramasamy Ravi, Dilip Nandwani

Agricultural and Environmental Sciences Faculty Research

This study was carried out to compare the sensory qualities of leafy green vegetables (collard, kale, lettuce and swiss chard) grown under organic and conventional production systems. Four leafy greens were produced on an organically and conventionally managed research farm of Tennessee State University, Nashville, TN in Spring 2019 and 2020. Crops in a conventional field were grown in the open field, whereas in organic field crops were grown in the open and under three different row covers (agribon cloth, insect net and plastic). Row covers in organic systems were used to protect crops from insect damage. Plant samples were …

Three-Dimensional Graph Matching To Identify Secondary Structure Correspondence Of Medium-Resolution Cryo-Em Density Maps, Bahareh Behkamal, Mahmoud Naghibzadeh, Mohammad Reza Saberi, Zeinab Amiri Tehranizadeh, Andrea Pagnani, Kamal Al Nasr

Computer Science Faculty Research

Cryo-electron microscopy (cryo-EM) is a structural technique that has played a significant role in protein structure determination in recent years. Compared to the traditional methods of X-ray crystallography and NMR spectroscopy, cryo-EM is capable of producing images of much larger protein complexes. However, cryo-EM reconstructions are limited to medium-resolution (~4–10 Å) for some cases. At this resolution range, a cryo-EM density map can hardly be used to directly determine the structure of proteins at atomic level resolutions, or even at their amino acid residue backbones. At such a resolution, only the position and orientation of secondary structure elements (SSEs) such …

Identification And Genetic Characterization Of Pseudomonas Syringae Pv. Syringae From Sweet Cherry In Turkey, Cansu Oksel, Farhat A. Avin, Mustafa Mirik, Fulya Baysal-Gurel

Agricultural and Environmental Sciences Faculty Research

Pseudomonas syringae pv. syringae (Pss), which causes bacterial canker, is the most polyphagous bacterium in the P. syringae complex due to its broad host range. This pathogen is considered the major bacterial disease in cherry orchards. In this study, several samples were collected from infected sweet cherry trees in different locations of the Marmara region in Turkey between 2016-2018. Sixty-three isolates were identified as Pss by pathogenicity, LOPAT, GATTa, and MALDI-TOF MS tests. Total genomic DNA was extracted to confirm identity, followed by PCR amplification of syrB and cfl genes. Out of 63 isolates, 12 were randomly selected for Repetitive …

Relationship Of Cultivated Grain Amaranth Species And Wild Relative Accessions, Ranjita Thapa, Matthew Edwards, Matthew W. Blair

Agricultural and Environmental Sciences Faculty Research

Amaranthus is a genus of C4 dicotyledonous herbaceous plants, and three New World species have been domesticated to produce grain crops with light colored seed which are classified as pseudo-cereals rich in protein and minerals. A core collection of grain amaranths and immediate precursor species has been established, representing the closest related species. The goal of this study was to evaluate the genetic diversity in that collection of cultivated and wild species, using competitive allele single nucleotide polymorphism markers. A secondary objective was to determine the relationships among the three cultivated species and non-domesticated Amaranthus, while a third objective was …

Soil Bacteria In Urban Community Gardens Have The Potential To Disseminate Antimicrobial Resistance Through Horizontal Gene Transfer, Abdullah Ibn Mafiz, Yingshu He, Wei Zhang, Yifan Zhang

Agricultural and Environmental Sciences Faculty Research

Fifteen soil and 45 vegetable samples from Detroit community gardens were analyzed for potential antimicrobial resistance contamination. Soil bacteria were isolated and tested by antimicrobial susceptibility profiling, horizontal gene transfer, and whole-genome sequencing. High-throughput 16S rRNA sequencing analysis was conducted on collected soil samples to determine the total bacterial composition. Of 226 bacterial isolates recovered, 54 were from soil and 172 from vegetables. A high minimal inhibitory concentration (MIC) was defined as the MIC greater than or equal to the resistance breakpoint of Escherichia coli for Gram-negative bacteria or Staphylococcus aureus for Gram-positive bacteria. The high MIC was observed in …

Immunometabolic Dysregulation At The Intersection Of Obesity And Covid-19, Collins N. Khwatenge, Marquette Pate, Laura C. Miller, Yongming Sang

Agricultural and Environmental Sciences Faculty Research

Obesity prevails worldwide to an increasing effect. For example, up to 42% of American adults are considered obese. Obese individuals are prone to a variety of complications of metabolic disorders including diabetes mellitus, hypertension, cardiovascular disease, and chronic kidney disease. Recent meta-analyses of clinical studies in patient cohorts in the ongoing coronavirus-disease 2019 (COVID-19) pandemic indicate that the presence of obesity and relevant disorders is linked to a more severe prognosis of COVID-19. Given the significance of obesity in COVID-19 progression, we provide a review of host metabolic and immune responses in the immunometabolic dysregulation exaggerated by obesity and the …

High-Fat Diet-Induced Obese Effects Of Adipocyte-Specific Cxcr2 Conditional Knockout In The Peritoneal Tumor Microenvironment Of Ovarian Cancer, Deokyeong Choe, Eun-Sook Lee, Alicia Beeghly-Fadiel, Andrew J. Wilson, Margaret M. Whalen, Samuel E. Adunyah, Deok-Soo Son

Chemistry Faculty Research

Obesity contributes to ovarian cancer (OC) progression via tumorigenic chemokines. Adipocytes and OC cells highly express CXCR2, and its ligands CXCL1/8, respectively, indicating that the CXCL1/8-CXCR2 axis is a molecular link between obesity and OC. Here, we investigated how the adipocyte-specific CXCR2 conditional knockout (cKO) affected the peritoneal tumor microenvironment of OC in a high-fat diet (HFD)-induced obese mouse model. We first generated adipocyte-specific CXCR2 cKO in mice: adipose tissues were not different in crown-like structures and adipocyte size between the wild-type (WT) and cKO mice but expressed lower levels of CCL2/6 compared to the obese WT mice. HFD-induced obese …

Short-Term Canopy And Understory Nitrogen Addition Differ In Their Effects On Seedlings Of Dominant Woody Species In A Subtropical Evergreen Broadleaved Forest, Jun Wang, Dafeng Hui, Hai Ren, Nan Liu, Zhongyu Sun, Long Yang, Hongfang Lu

Biology Faculty Research

As atmospheric nitrogen (N) deposition continues to increase, information on how N deposition affects seedling performance of tree species is critical for predicting forest regeneration. In this study, we examined the effects of canopy N addition at 25 and 50 kg ha−1 year−1 of N (CAN25 and CAN50), and understory N addition at 25 and 50 kg ha−1 year−1 of N (UAN25 and UAN50) on the survival, physiology, and growth of seedlings of two dominant woody species (Schima superba and Ardisia quinquegona) that were transplanted into a subtropical evergreen broadleaved forest. At two years after transplanting, understory N additon greatly …

Automatic Identification And Monitoring Of Plant Diseases Using Unmanned Aerial Vehicles: A Review, Krishna Neupane, Fulya Baysal-Gurel

Agricultural and Environmental Sciences Faculty Research

Disease diagnosis is one of the major tasks for increasing food production in agriculture. Although precision agriculture (PA) takes less time and provides a more precise application of agricultural activities, the detection of disease using an Unmanned Aerial System (UAS) is a challenging task. Several Unmanned Aerial Vehicles (UAVs) and sensors have been used for this purpose. The UAVs’ platforms and their peripherals have their own limitations in accurately diagnosing plant diseases. Several types of image processing software are available for vignetting and orthorectification. The training and validation of datasets are important characteristics of data analysis. Currently, different algorithms and …

Identification Of Bacterial Wilt (Erwinia Tracheiphila) Resistances In Usda Melon Collection, Bimala Acharya, Lucas Mackasmiel, Ali Taheri, Christine A. Ondzighi-Assoume, Yiqun Weng, C. Korsi Dumenyo

Agricultural and Environmental Sciences Faculty Research

Bacterial wilt (BW) caused by the Gram-negative bacterium, Erwinia tracheiphila (Et.), is an important disease in melon (Cucumis melo L.). BW-resistant commercial melon varieties are not widely available. There are also no effective pathogen-based disease management strategies as BW-infected plants ultimately die. The purpose of this study is to identify BW-resistant melon accessions in the United States Department of Agriculture (USDA) collection. We tested 118 melon accessions in two inoculation trials under controlled environments. Four-week-old seedlings of test materials were mechanically inoculated with the fluorescently (GFP) labeled or unlabeled E. tracheiphila strain, Hca1-5N. We recorded the number of days to …

Harness Organoid Models For Virological Studies In Animals: A Cross-Species Perspective, Yongming Sang, Laura C. Miller, Rahul K. Nelli, Luis Gabriel Giménez-Lirola

Agricultural and Environmental Sciences Faculty Research

Animal models and cell culture in vitro are primarily used in virus and antiviral immune research. Whereas the limitation of these models to recapitulate the viral pathogenesis in humans has been made well aware, it is imperative to introduce more efficient systems to validate emerging viruses in both domestic and wild animals. Organoids ascribe to representative miniatures of organs (i.e., mini-organs), which are derived from three-dimensional culture of stem cells under respective differential conditions mimicking endogenous organogenetic niches. Organoids have broadened virological studies in the human context, particularly in recent uses for COVID19 research. This review examines the status and …

Effect Of Volatile Compounds Produced By Selected Bacterial Endophytes In Promoting Plant Growth, Asha Maheshwari, Margaret T. Mmbaga, Bandana Bhusal, Christine A. Ondzighi-Assoume

Agricultural and Environmental Sciences Faculty Research

Bacterial endophytes selected for their capability to suppress diverse fungal pathogens in vitro and in greenhouse studies have been shown to promote plant growth. The effect of volatile compounds emitted by selected bacteria on plant growth in Arabidopsis thaliana, tomato (Solanum lycopersicum), sweet pepper (Capsicum annuum), and cucumbers (Cucumis sativus) was evaluated on container-grown plants nested above bacterial cultures, with roots exposed to the volatiles without direct contact between bacterial cells and the plant roots. Significant increases in plant growth were observed in plant height, root length, leaf size, fresh weight, and chlorophyll content in all plants tested. Although diverse …

Association Of Oral Microbiota With Lung Cancer Risk In A Low-Income Population In The Southeastern Usa, Jiajun Shi, Yaohua Yang, Hua Xie, Xiaofei Wang, Jie Wu, Jirong Long, Regina Courtney, Xiao-Ou Shu, Wei Zheng, William J. Blot, Qiuyin Cai

Biology Faculty Research

Purpose

Oral microbiome plays an important role in oral health and systemic diseases, including cancer. We aimed to prospectively investigate the association of oral microbiome with lung cancer risk.

Methods

We analyzed 156 incident lung cancer cases (73 European Americans and 83 African Americans) and 156 individually matched controls nested within the Southern Community Cohort Study. Oral microbiota were assessed using 16S rRNA gene sequencing in pre-diagnostic mouth rinse samples. Paired t test and the permutational multivariate analysis of variance test were used to evaluate lung cancer risk association with alpha diversity or beta diversity, respectively. Conditional logistic regression models …

Organic And Conventional Sweetpotato Production In The Southeastern Of United States: A Comparative Analysis, Sochinwechi Nwosisi, Prabodh Illukpitiya, Dilip Nandwani, Ismail Tubosun Arebi, Obinna Nwosisi

Agricultural and Environmental Sciences Faculty Research

Background

There has been a piqued interest in alternative agricultural production systems that are environmentally friendly due to concerns on how sustainable it is to grow conventionally. However, in the producer’s point of view, economic returns are an important issue in decision-making in adaptation. The purpose of this study is to assess the economic risk of conventional and organic sweetpotato production in the Southeastern US. The primary and secondary data were used for the analysis. We identified risk variables in stochastic profit function and performed Monte Carlo simulation in analyzing profitability and economic risk of conventional and organic production systems. …

Antibacterial Properties Of Citric Acid/Β-Alanine Carbon Dots Against Gram-Negative Bacteria, Anju Pandey, Asmita Devkota, Zeinab Yadegari, C. Korsi Dumenyo, Ali Taheri

Agricultural and Environmental Sciences Faculty Research

While multi-drug resistance in bacteria is an emerging concern in public health, using carbon dots (CDs) as a new source of antimicrobial activity is gaining popularity due to their antimicrobial and non-toxic properties. Here we prepared carbon dots from citric acid and β-alanine and demonstrated their ability to inhibit the growth of diverse groups of Gram-negative bacteria, including E. coli, Salmonella, Pseudomonas, Agrobacterium, and Pectobacterium species. Carbon dots were prepared using a one-pot, three-minute synthesis process in a commercial microwave oven (700 W). The antibacterial activity of these CDs was studied using the well-diffusion method, and their minimal inhibitory concentration …

Response Of Cover Crops To Phytopythium Vexans, Phytophthora Nicotianae, And Rhizoctonia Solani, Major Soilborne Pathogens Of Woody Ornamentals, Milan Panth, Anthony L. Witcher, Fulya Baysal-Gurel

Agricultural and Environmental Sciences Faculty Research

Management of plant diseases is a subject of concern for researchers as well as growers. Different management practices are being developed and used to combat the rising number of plant pathogens, which threaten nursery crop production. Use of cover crops for sustainable management of soilborne diseases is being explored as an alternative strategy to the chemicals. However, the potential threat of these cover crops acting as a secondary host of these devastating soilborne pathogens has not been described. We studied the response of the major cover crops being used by woody ornamental growers in the Southeastern United States to Phytopythium …

Assessing The Impact Of Organic Versus Conventional Agricultural Management On Soil Hydraulic Properties In A Long-Term Experiment, Abdelrahman Alfahham, Matthew T. Amato, Emmanuel Omondi, Daniel Giménez, Alain F. Plante

Agricultural and Environmental Sciences Faculty Research

Investigating the effects of various agricultural management systems on soil hydraulic properties in long-term field experiments allows farmers to evaluate their efficacy in mitigating the effects of droughts and floods, which are expected to intensify in the coming decades. This study's main objective was to quantify soil structural and hydraulic properties in plots under organic manure, organic leguminous, and conventional agricultural management and related tillage practices at Rodale Institute's Farming Systems Trial. Soil cores were collected at depths of 0–10, 10–20, and 20–30 cm and analyzed for soil water retention, saturated hydraulic conductivity (Ksat), soil organic C (SOC), bulk density, …

The Effects Of Tunnel Technology On Crop Productivity And Livelihood Of Smallholder Farmers In Nepal, Diwakar Kc, Dinesh Jamarkattel, Tek Maraseni, Dilip Nandwani, Pratibha Karki

Agricultural and Environmental Sciences Faculty Research

Technologies-based production practices are critical for agricultural growth and sustainable development in low-income countries like Nepal. In the last few years, tunnel house has been increasingly promoted as tools to enhance smallholder farmers’ livelihood and tackle climate adversaries. However, little is known about what factor determines its adoption and whether it helps smallholders adapt to climate change and experience better livelihood. We address these gaps using the cross-sectional survey data collected from 62 adopters and 92 non-adopters in three municipalities of Bagmati Province. We employed descriptive analysis and probit model and found out that age, farm size, and ethnicity strongly …

Editorial: Amaranthus: Naturally Stress-Resistant Resources For Improved Agriculture And Human Health, Chance W. Riggins, Ana Paulina Barba De La Rosa, Matthew W. Blair, Eduardo Espitia-Rangel

Agricultural and Environmental Sciences Faculty Research

No abstract provided.

Decomposition Of Microbial Necromass Is Divergent At The Individual Taxonomic Level In Soil, Weiling Dong, Alin Song, Huaqun Yin, Xueduan Liu, Jianwei Li, Fenliang Fan

Agricultural and Environmental Sciences Faculty Research

The turnover of microbial biomass plays an important part in providing a significant source of carbon (C) to soil organic C. However, whether the decomposition of microbial necromass (non-living microbial biomass) in the soil varies at the individual taxa level remains largely unknown. To fill up these gaps, we compared the necromass decomposition of bacterial and archaeal taxa by separating live microbial biomass with 18O-stable isotope probing from dead microbial biomass in soil. Our results showed that most of the microbial necromass at the operational taxonomic unit level (88.51%), which mainly belong to Acidobacteria, Actinobacteria, Gemmatimonadetes, and Proteobacteria, decomposed significantly …

Identifying Tennessee School-Based Agricultural Education Student Growth And Program Accountability Metrics, Ashton Street, Christopher T. Stripling, John C. Ricketts, Nathan W. Conner, Christopher Boyer

Extension Publications

Over the years, accountability in education has transformed from the primary focus being the school as a whole to the individual teacher. The purpose of this study was to determine the metrics Tennessee school-based agricultural education teachers perceive as indicators of excellent total programs (classroom instruction, FFA, SAE), and a modified Delphi study was used to seek a consensus. The following nine metrics were retained: (a) pesticide certification, (b) program of activities, (c) number of students participating in CDEs, (d) chapter community service hours, (e) total number of FFA activities, (f) number of CDEs coached, (g) at least one proficiency …

Soil Health Beneath Amended Switchgrass: Effects Of Biochar And Nitrogen On Active Carbon And Wet Aggregate Stability, Priya Saini, Jason P. De Koff, Richard Link, Chris Robbins

Agricultural and Environmental Sciences Faculty Research

Perennial crops, like switchgrass (Panicum virgatum L.), are important for bioenergy production and long-term carbon sequestration. Biochar, a byproduct of certain bioenergy production processes, is also identified as a potential tool for carbon sequestration and soil quality improvements, especially in marginal soils. Despite the focus on switchgrass, soil health characteristics under switchgrass production for biomass are unclear. This study focused on identifying the effects of four N rates (0, 17, 34, and 67 kg N ha−1) and biochar application (0 and 9 Mg ha−1) in a 3-year switchgrass field study on a silt loam soil. Soil active carbon (AC) and …

Genome Wide Association Mapping Of Root Traits In The Andean Genepool Of Common Bean (Phaseolus Vulgaris L.) Grown With And Without Aluminum Toxicity, Daniel Ambachew, Matthew W. Blair

Agricultural and Environmental Sciences Faculty Research

Common bean is one of the most important grain legumes for human diets but is produced on marginal lands with unfavorable soil conditions; among which Aluminum (Al) toxicity is a serious and widespread problem. Under low pH, stable forms of Al dissolve into the soil solution and as phytotoxic ions inhibit the growth and function of roots through injury to the root apex. This results in a smaller root system that detrimentally effects yield. The goal of this study was to evaluate 227 genotypes from an Andean diversity panel (ADP) of common bean and determine the level of Al toxicity …

Identification Of Fusarium Commune, The Causal Agent Of Postharvest Zinnia Meltdown Disease In Tennessee, Ravi Bika, Fulya Baysal-Gurel

Agricultural and Environmental Sciences Faculty Research

The cut flower growers of the eastern and southern United States are threatened with postharvest meltdown of zinnia (Zinnia elegans), which reduces yield and income as well as limiting opportunities for production expansion. Disease symptoms such as bending of the stem just below the flower were visually apparent on zinnia cut flowers. The objective of this study was to identify the causal agent related to zinnia meltdown. A total of 20 symptomatic zinnia cut flower stems were collected from Tennessee. Several Fusarium-like colonies with micro and macroconidia were isolated from the base and bend area of stems on potato dextrose …

Effects Of Lactobacillus Reuteri And Streptomyces Coelicolor On Growth Performance Of Broiler Chickens, Sarayu Bhogoju, Collins N. Khwatenge, Thyneice Taylor-Bowden, Gabriel Oluwamuyiwa Akerele, Boniface M. Kimathi, Joseph Donkor, Samuel N. Nahashon

Agricultural and Environmental Sciences Faculty Research

There are well documented complications associated with the continuous use of antibiotics in the poultry industry. Over the past few decades, probiotics have emerged as viable alternatives to antibiotics; however, most of these candidate probiotic microorganisms have not been fully evaluated for their effectiveness as potential probiotics for poultry. Recent evaluation of a metagenome of broiler chickens in our laboratory revealed a prevalence of Lactobacillus reuteri (L. reuteri) and Actinobacteria class of bacteria in their gastrointestinal tract. In this study Lactobacillus reuteri and Streptomyces coelicolor (S. coelicolor) were selected as probiotic bacteria, encapsulated, and added into broiler feed at a …