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A Modified Delphi Study On Boxwood Blight Disease Management In The Us Nursery Industry, Bhawana Ghimire, Kumuditha Hikkaduwa Epa Liyanage, Charlie Hall, Fulya Baysal-Gurel

Agricultural and Environmental Sciences Faculty Research

Boxwood is one of the most popular evergreen shrubs in the United States, the production of which is currently challenged by boxwood blight, an emerging threat that has spread across 30 states. A thorough understanding of boxwood production, plant health, management practices and economic impact could aid in answering the needs of the nursery industry in managing this disease. An online modified Delphi survey was conducted to identify grower perceptions on processes, programs, and practices to limit or prevent the entry and spread of boxwood blight disease. The expert panel consisted of 29 nursery producers who represented a significant portion …

Regulation Of Cora, The Magnesium, Nickel, Cobalt Transporter, And Its Role In The Virulence Of The Soft Rot Pathogen, Pectobacterium Versatile Strain Ecc71, Caleb M. Kersey, Korsi Dumenyo

Agricultural and Environmental Sciences Faculty Research

Pectobacterium versatile (formally P. carotovorum) causes disease on diverse plant species by synthesizing and secreting copious amount of plant-cell-wall-degrading exoenzymes including pectate lyases, polygalacturonases, cellulases, and proteases. Exoenzyme production and virulence are controlled by many factors of bacterial, host, and environmental origin. The ion channel forming the magnesium, nickel, and cobalt transporter CorA is required for exoenzyme production and full virulence in strain Ecc71. We investigated CorA’s role as a virulence factor and its expression in P. versatile. Inhibiting the transport function of CorA by growing a CorA+ strain in the presence of specific CorA inhibitor, cobalt (III) hexaammine (Co …

Snp Genotyping For Purity Assessment Of A Forage Oat (Avena Sativa L.) Variety From Colombia, Luis Fernando Campuzano-Duque, Diego Bejarano-Garavito, Javier Castillo-Sierra, Daniel Ricardo Torres-Cuesta, Andrés J. Cortés, Matthew Wohlgemuth Blair

Agricultural and Environmental Sciences Faculty Research

Single nucleotide polymorphism (SNP) markers have multiple applications in plant breeding of small grains. They are used for the selection of divergent parents, the identification of genetic variants and marker-assisted selection. However, the use of SNPs in varietal purity assessment is under-reported, especially for multi-line varieties from the public sector. In the case of variety evaluation, these genetic markers are tools for maintaining varietal distinctness, uniformity and stability needed for cultivar release of multi-line or pure-line varieties of inbred crops. The objective of this research was to evaluate the purity and relationships of one original (AV-25) and two multi-line sub-populations …

Efficacy And Timing Of Application Of Fungicides, Biofungicides, Host-Plant Defense Inducers, And Fertilizer To Control Phytophthora Root Rot Of Flowering Dogwoods In Simulated Flooding Conditions In Container Production, Krishna Neupane, Bhawana Ghimire, Fulya Baysal-Gurel

Agricultural and Environmental Sciences Faculty Research

Phytophthora root rot caused by Phytophthora cinnamomi Rands is one of the major diseases of flowering dogwoods (Cornus florida L.). The severity of root rot disease increases when the plants are exposed to flooding conditions. A study was conducted to determine the efficacy and timing of application of different fungicides, biofungicides, host plant defense inducers, and fertilizer to manage Phytophthora root rot in month-old seedlings in simulated flooding events for 1-, 3-, and 7- days. Preventative treatments were drench applied 3 weeks and 1 week before flooding whereas curative treatments were applied 24 hrs. after flooding. Dogwood seedlings were inoculated …

Influence Of Citrate And Phosphate On The Adsorption Of Adenosine-5′-Monophosphate At The Hematite Water Interface, Sudipta Rakshit, Avedananda Ray, Ali Taheri, Michael E. Essington

Agricultural and Environmental Sciences Faculty Research

Nucleic acid derived organic phosphorus (Po) is an important source of plant available P when degraded to inorganic phosphate (P(V)i). It is known that when nucleic acids or components are adsorbed on mineral surfaces, the enzymatic degradation is hindered or delayed. Thus, understanding adsorption/desorption mechanisms of nucleic acids and their derivatives are key to assess the biogeochemical pathways of Po cycling. Here we report adsorption mechanisms of adenosine-5′-monophosphate (AMP) on hematite, a common iron oxide mineral, under various solution properties using macroscopic and in situ attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopic probes. The effects of citrate, mimicking organic …

Editorial: Accelerating Genetic Gains In Pulses, Aditya Pratap, Shiv Kumar, Patricia L. Polowick, Matthew W. Blair, Michael Baum

Agricultural and Environmental Sciences Faculty Research

No abstract provided.

Effect Of Winter Canola Cultivar On Seed Yield, Oil, And Protein Content, Kyle D. Mcgeary, Jason P. De Koff, Bharat Pokharel, Richard Link, Priya Saini, Taqdeer Gill

Agricultural and Environmental Sciences Faculty Research

Winter canola (Brassica napus L.) production has increased in the United States over the past several decades; however, there is little research in the southeastern United States on its agronomic production and growth characteristics under different nitrogen (N) fertilizer rates. The objectives of this study were to determine the effects of N rates on winter mortality, yield, oil and protein content, and seedpod shatter resistance across cultivars. Canola was grown in a randomized split complete block design with four replicates under five different N rates (0, 56, 112, 168, and 224 kg N ha−1) with four different cultivars (Hekip, Inspiration, …

A Rulebook For Peptide Control Of Legume–Microbe Endosymbioses, Sonali Roy, Lena Maria Müller

Agricultural and Environmental Sciences Faculty Research

Plants engage in mutually beneficial relationships with microbes, such as arbuscular mycorrhizal fungi or nitrogen-fixing rhizobia, for optimized nutrient acquisition. In return, the microbial symbionts receive photosynthetic carbon from the plant. Both symbioses are regulated by the plant nutrient status, indicating the existence of signaling pathways that allow the host to fine-tune its interactions with the beneficial microbes depending on its nutrient requirements. Peptide hormones coordinate a plethora of developmental and physiological processes and, recently, various peptide families have gained special attention as systemic and local regulators of plant–microbe interactions and nutrient homeostasis. In this review, we identify five 'rules' …

Carbon-Sensitive Pedotransfer Functions For Plant Available Water, Dianna K. Bagnall, Cristine L. S. Morgan, Michael Cope, Gregory M. Bean, Shannon Cappellazzi, Kelsey Greub, Daniel Liptzin, Charlotte L. Norris, Elizabeth Rieke, Paul Tracy, Ezra Aberle, Amanda Ashworth, Oscar Bañuelos Tavarez, Andy Bary, Roland Louis Baumhardt, Alberto Borbón Gracia, Daniel Brainard, Jameson Brennan, Dolores Briones Reyes, Darren Bruhjell, Cameron Carlyle, James Crawford, Cody Creech, Steven Culman, William Deen, Curtis Dell, Justin Derner, Thomas Ducey, Sjoerd Willem Duiker, Miles Dyck, Benjamin Ellert, Martin Entz, Avelino Espinosa Solorio, Steven J. Fonte, Simon Fonteyne, Ann-Marie Fortuna, Jamie Foster, Lisa Fultz, Audrey V. Gamble, Charles Geddes, Deirdre Griffin-Lahue, John Grove, Stephen K. Hamilton, Xiying Hao, ‪Zachary D. Hayden, Julie Howe, James Ippolito, Gregg Johnson, Mark Kautz, Newell Kitchen, Sandeep Kumar, Kirsten Kurtz, Francis Larney, Katie Lewis, Matt Liebman, Antonio Lopez Ramirez, Stephen Machado, Bijesh Maharjan, Miguel Angel Martinez Gamiño, William May, Mitchel Mcclaran, Marshall Mcdaniel, Neville Millar, Jeffrey P. Mitchell, Philip A. Moore, Amber Moore, Manuel Mora Gutiérrez, Kelly A. Nelson, Emmanuel Omondi, Shannon Osborne, Leodegario Osorio Alcalá, Philip Owens, Eugenia M. Pena-Yewtukhiw, Hanna Poffenbarger, Brenda Ponce Lira, Jennifer Reeve, Timothy Reinbott, Mark Reiter, Edwin Ritchey, Kraig L. Roozeboom, Ichao Rui, Amir Sadeghpour, Upendra M. Sainju, Gregg Sanford, William Schillinger, Robert R. Schindelbeck, Meagan Schipanski, Alan Schlegel, Kate Scow, Lucretia Sherrod, Sudeep Sidhu, Ernesto Solís Moya, Mervin St. Luce, Jeffrey Strock, Andrew Suyker, Virginia Sykes, Haiying Tao, Alberto Trujillo, Laura L. Van Eerd, Nele Verhulst, Tony John Vyn, Yutao Wang, Dexter Watts, David Wright, Tiequan Zhang, Charles Wayne Honeycutt

Agricultural and Environmental Sciences Faculty Research

Currently accepted pedotransfer functions show negligible effect of management-induced changes to soil organic carbon (SOC) on plant available water holding capacity (θAWHC), while some studies show the ability to substantially increase θAWHC through management. The Soil Health Institute's North America Project to Evaluate Soil Health Measurements measured water content at field capacity using intact soil cores across 124 long-term research sites that contained increases in SOC as a result of management treatments such as reduced tillage and cover cropping. Pedotransfer functions were created for volumetric water content at field capacity (θFC) and permanent wilting point (θPWP). New pedotransfer functions had …

Effect Of Mulch Type And Depth On Rooting Of Stem Cuttings And Weed Control In Containers, Isha Poudel, Anthony L. Witcher

Agricultural and Environmental Sciences Faculty Research

Weeds are a major problem in cutting propagation and compete with the main crop for water, sunlight, and nutrients, thus reducing growth and marketable quality of rooted cuttings. Due to the high labor cost of hand weeding, mulches can be an alternative method for weed control in the propagation environment. The objective of this research was to determine the effect of mulches (coarse vermiculite, rice hulls, paper pellets, and pine pellets) on rooting of stem cuttings and weed control when applied at 0.5- and 1-inch depths. Cuttings of three plant species [‘Nanho Blue’ butterfly bush (Buddleja davidii), ‘Catawba’ …

Application Of Synthetic Peptide Cep1 Increases Nutrient Uptake Rates Along Plant Roots, Sonali Roy, Marcus Griffiths, Ivone Torres-Jerez, Bailey Sanchez, Elizabeth Antonelli, Divya Jain, Nicholas Krom, Shulan Zhang, Larry M. York, Wolf-Rüdiger Scheible, Michael Udvardi

Agricultural and Environmental Sciences Faculty Research

The root system of a plant provides vital functions including resource uptake, storage, and anchorage in soil. The uptake of macro-nutrients like nitrogen (N), phosphorus (P), potassium (K), and sulphur (S) from the soil is critical for plant growth and development. Small signaling peptide (SSP) hormones are best known as potent regulators of plant growth and development with a few also known to have specialized roles in macronutrient utilization. Here we describe a high throughput phenotyping platform for testing SSP effects on root uptake of multiple nutrients. The SSP, CEP1 (C-TERMINALLY ENCODED PEPTIDE) enhanced nitrate uptake rate per unit root …

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 …

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 …

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 …

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 …

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. …

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 …

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.

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 …

A Research Road Map For Responsible Use Of Agricultural Nitrogen, Michael Udvardi, Frederick E. Below, Michael J. Castellano, Alison J. Eagle, Ken E. Giller, Jagdish Kumar Ladha, Xuejun Liu, Tai Mcclellan Maaz, Barbara Nova-Franco, Nandula Raghuram, G. Philip Robertson, Sonali Roy, Malay Saha, Susanne Schmidt, Mechthild Tegeder, Larry M. York, John W. Peters

Agricultural and Environmental Sciences Faculty Research

Nitrogen (N) is an essential but generally limiting nutrient for biological systems. Development of the Haber-Bosch industrial process for ammonia synthesis helped to relieve N limitation of agricultural production, fueling the Green Revolution and reducing hunger. However, the massive use of industrial N fertilizer has doubled the N moving through the global N cycle with dramatic environmental consequences that threaten planetary health. Thus, there is an urgent need to reduce losses of reactive N from agriculture, while ensuring sufficient N inputs for food security. Here we review current knowledge related to N use efficiency (NUE) in agriculture and identify research …

Fire Ant Venom Alkaloids: Possible Control Measure For Soilborne And Foliar Plant Pathogens, Sujan Dawadi, Fulya Baysal-Gurel, Karla M. Addesso, Prabha Liyanapathiranage, Terri Simmons

Agricultural and Environmental Sciences Faculty Research

The purpose of this study was to evaluate fire ant venom alkaloids and an alarm pheromone analog against several plant pathogens, including Botrytis cinerea, Fusarium oxysporum, Phytophthora nicotianae, P. cryptogea, Pseudomonas syringae, Phytopythium citrinum, Rhizoctonia solani, Sclerotonia rolfsii, Xanthomonas axonopodis, and X. campestris. All pathogens were tested against red imported fire ant venom alkaloid extract and alarm pheromone compound for growth inhibition in in vitro assay. The venom alkaloid extract inhibited fungal and oomycete pathogens. Neither of the treatments were effective against bacterial pathogens. Three soilborne pathogens, P. nicotianae, R. solani, F. oxysporum, and one foliar pathogen, B. cinerea were …

Sources Of Resistance To Common Bacterial Blight And Charcoal Rot Disease For The Production Of Mesoamerican Common Beans In The Southern United States, Daniel Ambachew, Jacqueline Joshua, Margaret T. Mmbaga, Matthew W. Blair

Agricultural and Environmental Sciences Faculty Research

The gene pool of Mesoamerican common beans (Phaseolus vulgaris L.) includes genotypes in the small-to-medium-size seeded dry beans, as well as some snap beans from hotter environments adapted to the Southeastern United States. However, the warm and humid climate of the Southeastern United States is conducive to diseases such as Common Bacterial Blight (CBB) and Charcoal Rot (CR). The pathogens for these two diseases can survive long periods in infested soil or on seeds and are difficult to control through pesticides. Hence, field-level resistance would be the best management strategy for these diseases. The goals of this study were (1) …

Management Of Powdery Mildew On Ninebark Using Sanitizers, Biorational Products, And Fungicides, Fulya Baysal-Gurel, Ravi Bika

Agricultural and Environmental Sciences Faculty Research

Ninebark (Physocarpus opulifolius) is a popular ornamental shrub and considered a hardy and tough plant that can thrive in different environmental conditions and resist diseases. However, powdery mildew, caused by Podosphaera physocarpi, can severelyaffect ninebark, deteriorating the ornamental value and making them unmarketable. Only a few studies have been done in managing powdery mildew of ninebark. The current study focuses on evaluating and identifying effective products (sanitizers, biorational products, and fungicides) for the management of powdery mildew disease of ninebark. A total of 12 treatments, including nontreated control, were studied. The experiment was arranged in randomized complete block design with …

Allelic Diversity At Abiotic Stress Responsive Genes In Relationship To Ecological Drought Indices For Cultivated Tepary Bean, Phaseolus Acutifolius A. Gray, And Its Wild Relatives, María A. Buitrago-Bitar, Andrés J. Cortés, Felipe López-Hernández, Jorge M. Londoño-Caicedo, Jaime E. Muñoz-Florez, L. Carmenza Muñoz, Matthew Wohlgemuth Blair

Agricultural and Environmental Sciences Faculty Research

Some of the major impacts of climate change are expected in regions where drought stress is already an issue. Grain legumes are generally drought susceptible. However, tepary bean and its wild relatives within Phaseolus acutifolius or P. parvifolius are from arid areas between Mexico and the United States. Therefore, we hypothesize that these bean accessions have diversity signals indicative of adaptation to drought at key candidate genes such as: Asr2, Dreb2B, and ERECTA. By sequencing alleles of these genes and comparing to estimates of drought tolerance indices from climate data for the collection site of geo-referenced, tepary bean accessions, we …

Impact Of Zinc Excess On Germination, Growth Parameters And Oxidative Stress Of Sweet Basil (Ocimum Basilicum L.), Hela Mahmoudi, Imene Ben Salah, Wafa Zaouali, Walid Zorrig, Ameni Smaoui, Ali Taheri, Margaret Gruber, Zeineb Ouerghi, Karim Hosni

Agricultural and Environmental Sciences Faculty Research

In the present study, the effects of elevated zinc concentrations on germination, physiological and biochemical parameters were investigated in basil (Ocimum basilicum L.). Results indicate that zinc excess (1–5 mM ZnSO4) did not affect germination process, but it drastically reduced vigor index and radicle elongation, and induced oxidative stress. Exposure of basil plants to 400 and 800 µM Zn decreased aerial parts and roots dry biomass, root length and leaf number. Under these conditions, the reduction of plant growth was associated with the formation of branched and abnormally shaped brown roots. Translocation factor < 1 and bioconcentration factor > 1 was observed for 100 µM Zn …