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Resolving The Position Of Astragalus Borysthenicus Klokov Within The Astragalus L. Species, Nataliia Karpenko, Viktoriia Martyniuk, Oksana Tyshchenko, Andrii Tarieiev, Ayten Tekpinar, Vitaliia Didenko, Igor Kostikov

Turkish Journal of Botany

The present study is focused on several species from the genus Astragalus L. with the aim to clarify the taxonomic status of Ukrainian local endemic species Astragalus borysthenicus Klokov, which is sometimes considered a synonym to A. onobrychis L. In this study, the morphological features, current taxonomy, taxonomical history, and phylogenetic analysis based on rDNA Bayesian inference, as well as comparative analysis of ITS1 and ITS2 secondary structures, were investigated. It was found that A. borysthenicus is distant from A. onobrychis according to phylogenetic analysis. Moreover, A. borysthenicus has differences from the investigated taxa in its secondary structures of ITS1 …

Managing Wicked Herbicide-Resistance: Lessons From The Field, Jill Schroeder, Michael Barrett, David R. Shaw, Amy B. Asmus, Harold Coble, David Ervin, Raymond A. Jussaume Jr., Michael D. K. Owen, Ian Burke, Cody F. Creech, A. Stanley Culpepper, William S. Curran, Darrin M. Dodds, Todd A. Gaines, Jeffrey L. Gunsolus, Bradley D. Hanson, Prashant Jha, Annie E. Klodd, Andrew R. Kniss, Ramon G. Leon, Sandra Mcdonald, Don W. Morishita, Brian J. Schutte, Christy L. Sprague, Phillip W. Stahlman, Larry E. Steckel, Mark J. Vangessel

Department of Agronomy and Horticulture: Faculty Publications

Herbicide resistance is ‘wicked’ in nature; therefore, results of the many educational efforts to encourage diversification of weed control practices in the United States have been mixed. It is clear that we do not sufficiently understand the totality of the grassroots obstacles, concerns, challenges, and specific solutions needed for varied crop production systems. Weed management issues and solutions vary with such variables as management styles, regions, cropping systems, and available or affordable technologies. Therefore, to help the weed science community better understand the needs and ideas of those directly dealing with herbicide resistance, seven half-day regional listening sessions were held …

Intraspecific Genetic Variation, Population Structure, And Performance Of The Invasive Aquatic Macrophyte Eurasian Watermilfoil (Myriophyllum Spicatum) In Waterbodies With And Without Histories Of Chemical Herbicide Treatment Across Michigan, Taylor Zallek

Dissertations, Master's Theses and Master's Reports

Populations of invasive species are often subjected to novel selective forces in the form of anthropogenic control agents in their introduced ranges. These control agents, applied unevenly among populations within a species’ new range, can send invasive populations on drastically different evolutionary and ecological trajectories. In these studies, we aimed to see if different histories of chemical herbicide treatment are differentially influencing the genetic diversity, structure, and performance of populations of invasive watermilfoil (Myriophyllum spicatum and M. spicatum x M. sibiricum hybrids) from waterbodies in the state of Michigan. We sampled ten waterbodies with different histories of herbicide treatment …

Floral Resource Availability And Butterfly Community Characteristics In Cp-42 Pollinator Habitat Plantings, Ethan Marburger, Corinne Myers, Mark Myers

Undergraduate Student Work

Prairies once covered approximately 85% of Iowa, but due to extensive habitat loss less than 0.1% of native prairies remain (Smith 1998). Habitat loss in Iowa has been driven by agricultural expansion and intensification, and has resulted in the decline of many native insect pollinators. To curb habitat loss and restore habitat for pollinators, USDA’s Farm Service Agency (FSA) provides private landowners incentives to enroll agricultural land into the Conservation Reserve Program (CRP) Pollinator Habitat (CP-42) practice. The CP-42 conservation practice requires landowners to seed at least 9 species of pollinator friendly wildflowers, legumes, or shrubs on enrolled lands. CP-42 …

Correlation Between Wild Bee Populations And Vegetative Resources In The Conservation Reserve Program’S Pollinator Enhancement Plantings, Olivia Willoughby, Alyssa Burgert, Nathan Theel, Ai Wen

Undergraduate Student Work

Wild bee populations are in decline; and one of the main factors that caused this is habitat loss, which diminishes floral resources that bees utilize for nectar and pollen (Watanabe 2013)

The Conservation Reserve Program (CRP) aims to combat habitat loss by implementing ecological restorations that provide resources for a variety of different wildlife

In 2011, the CRP established a Pollinator Habitat Initiative called CP-42, which encompasses forbs and grasses to create adequate habitat for pollinators

A primary goal of this program is to enhance pollinator abundance and diversity

Soil Characteristics Affecting Weed Invasion On Conservation Reserve Program Pollinator Habitats, Jennifer Pauley

Undergraduate Student Work

The Conservation Reserve Program (CRP) is a land conservation program administered by the US Department of Agriculture Farm Service Agency (FSA) to improve water quality, prevent soil erosion, and create wildlife habitat.

• The CP-42 program provides cost share and an annual rental payment to farmers in order to establish native prairie species for pollinator habitat.

County NRCS technical staff make recommendations for seed mix to match the dominant soil moisture class in a parcel (e.g. dry, mesic, wet) with the appropriate plant species.

• There has been little to no research prior to the Biology SURP initiative to monitor …

Pollinator Power: Supporting Bees Through Ecoregion Specific Planting Guides, Maya Thomas

Scripps Senior Theses

The pollination of flowering crops by bees is an invaluable ecosystem service that supports biodiversity and much of the global agricultural system. Pollinators move pollen between the male structures of a plant to the female structures of a plant of the same species. This fertilizes the female plant, which then produces the next generation. This process also provides the pollinator with the nectar or pollen it needs to survive. While some plants transfer pollen through different means, the majority of plants need help from pollinators to reproduce. Depending on the means of pollination, pollination can be classified as abiotic or …

Interseeding Cover Crops To Suppress Weeds In Corn- Soybean Rotations In Kentucky, Victoria Leigh Stanton

Theses and Dissertations--Plant and Soil Sciences

Cover crops are typically sown between cash crops and can suppress weed emergence and growth. If cover crops are sown after cash crop harvest the system is left susceptible to weed emergence while they establish. Interseeding cover crops into a standing cash crop may limit this bare period by allowing cover crops to become established, go into dormancy, and then revive around cash crop senescence. Studies were conducted in Princeton and Lexington, KY, to determine (i) which corn pre-emergent herbicides and mixtures of herbicide active ingredients commonly used by Kentucky growers would impact interseeded cover crop density and biomass, (ii) …

Measured Soil Hydraulic Properties As Rzwqm2 Input To Simulate Soil Water Dynamics And Crop Evapotranspiration, Saadi Sattar Shahadha

Theses and Dissertations--Plant and Soil Sciences

Agricultural system models integrate many different processes that cannot all be measured in field experiments and help quantify soil water dynamics, crop evapotranspiration, and crop growth with high temporal resolution. Understanding soil water dynamics and crop evapotranspiration is essential to improve agricultural management of field crops. For example, the interaction between nitrogen application rate and water dynamics is not sufficiently understood. In most cases, model simulations deviate from field measurements, especially when model input parameters are indirectly and unspecifically derived. The extent to which measured soil hydraulic property inputs decrease the discrepancy between measured and simulated soil water status is …

Bioremoval Of Toxic Dye By Using Different Marine Macroalgae, Hanan Omar, Adel El-Gendy, Khairia Al-Ahmary

Turkish Journal of Botany

The removal of malachite green dye from aqueous solution by Ulva lactuca, Sargassum crassifolium, and Gracilaria corticata has been demonstrated in order to examine their potential use as low-cost adsorbents. The optimum pH (8.0), temperature (25 °C), contact time (150 min), and biomass (2.0 g) for removal of dye by algae are reported. The maximum removal percentage of the dye ranged between 95.6% and 98.3% by using Sargassum crassifolium at the optimal conditions. Minimum removal of dye by algae (69%-77.1%) was observed with the high dye concentration of 35 mg L-1 at the optimal conditions. Adsorption of the dye by …

A New Species Of Hygrophorus, H. Yadigarii Sp. Nov. (Hygrophoraceae), With An Isolated Systematic Position Within The Genus From The Colchic Part Of Turkey, Ertuğrul Sesli̇, Vladimir Antonin, Marco Contu

Turkish Journal of Botany

Hygrophorus yadigarii (Hygrophoraceae/Basidiomycota) is described as a new species for science based on basidiomata collected from Maçka, Trabzon, Turkey. The new taxon is quite different even from the closest relatives, easily distinguished by the other species because of its grayish to ash-colored, gregarious to subcaespitose, sticky basidioma; a slightly umbonate to depressed pileus; a cylindrical to clavate, grayish stipe; ellipsoid and smooth basidiospores; quite long basidia; clavate, cylindrical or narrowly utriform, apically pyriform or strangulated cheilocystidia; and gelatinous pileipellis. A description with field and micromorphological illustrations, a phylogenetic tree, a simple key, a comparison chart including similar species, and a …

Habitat Effects And Differences In The Reproductive Success Oforchis Punctulata And Orchis Purpurea (Orchidaceae), Spyros Tsiftsis, Vladan Djordjevic

Turkish Journal of Botany

The pollination success of two nonrewarding orchids in two coarse habitats was examined. The comparative results of Orchis punctulata and O. purpurea showed a significant differentiation. The fruit set of O. purpurea was significantly greater compared to O. punctulata, whereas both species also had significantly higher fruit set in the grassland compared to the forest. Although the pollination success of O. purpurea was not significantly correlated with plant height, inflorescence size, or nearest neighbor distance, these factors were found to be significantly correlated to the pollination success of O. punctulata. Among these factors, the nearest neighbor distance had the highest …

Pollen Morphology Of Scaligeria Dc. (Apiaceae) In Turkey, Ayşe Baldemi̇r, Şenol Alan, Aydan Acar Şahi̇n, Mehmet Yavuz Paksoy, Nur Münevver Pinar

Turkish Journal of Botany

In this study, the pollen morphology of all Scaligeria DC. species distributed in Turkey were studied with light and scanning electron microscopy for the first time. The aim is to contribute to knowledge of the variation among seven Scaligeria species, which have taxonomic problems, based on pollen morphological characteristics by population analysis. The pollen is radially symmetrical, isopolar, and tricolporate in all examined species. Pollen grains are prolate and subprolate with the polar axes ranging from 18.4 to 37 μm and the equatorial axes from 9.8 to 30 μm. Their polar shapes are triangular, triangular to subcircular, circular to subcircular, …

Isolation Of Potential Photosynthetic N2-Fixing Microbes From Topsoil Of Native Grasslands In South Dakota, Nanfang Wang, Shengni Tian, Liping Gu, Lan Xu, Yeyan Qiu, Trevor Van Den Top, Jose L. Gonzalez-Hernandez, Michael B. Hildreth, Shaoshan Li, Runbao Zhou

Natural Resource Management Faculty Publications

Nitrogen fertilizer is one of the most limiting factors and costly inputs in agriculture production. Current fossil fuel-dependent ammonia production is both energy intensive and environmentally damaging. An economically practical and environmentally friendly solution for the production of ammonia is urgently needed. Solar-powered N2-fixing cyanobacteria provide a unique opportunity and promise for applications in agriculture compared to all other N2-fixing bacteria that cannot use solar energy. Isolation of nitrogen-fixing microbes from the topsoil of native grasslands may have the potential to use them in crop fields as living ammonia factories. This may be a mechanism to free farmers from heavy …

Identifying And Characterizing Salt-Tolerant Alfalfa (Medicago Sativa Subsp Falcata Germplasm, Katelin E. Frerichs, Lan Xu

Natural Resource Management Faculty Publications

Soil salinity limits plant growth and crop production. More than 20% of cultivated land worldwide is affected by salinity. The situation is becoming more severe due to shifts in precipitation and evaporation patterns and improper irrigation. There is an urgent need to develop salt-tolerant, economically valuable plants to minimize the loss of and to sustain agricultural production. Alfalfa is one of the most extensively cultivated forage crops. Some yellow-flowered alfalfa (Medicago sativa subsp. falcata) have exhibited morphological and physiological drought tolerance. Since soil salinity is associated with physiological drought, it is reasonable to expect that these drought tolerant falcata populations …

Impacts Of Strategic Grazing And Fire On Soil Seed Bank Heterogeneity In Mixed-Grass Prairie, Kassidy Weathers, Lan Xu, Patricia Johnson

Natural Resource Management Faculty Publications

Native plant communities in the Northern Great Plains evolved under periodic fire and substantial grazing pressure from native herbivores, two main drivers maintaining the heterogeneity of grassland ecosystems. However, contemporary management practices focus on maximizing livestock production through fire suppression and uniform grazing strategies, resulting in decreased vegetation heterogeneity, species richness, wildlife habitat, and biodiversity. Objectives of this study were to evaluate and compare the effectiveness of patch-burn grazing (PBG) and winter-patch grazing (WPG) managements on soil seed bank heterogeneity in terms of species 1) richness, 2) composition, 3) abundance, and 4) diversity. Two soil cores (10-cm dia × 10-cm …

Growth, Fitness, And Overwinter Survival Of A Shattercane (Sorghum Bicolor Ssp. Drummondii) × Grain Sorghum (Sorghum Bicolor Ssp. Bicolor) F2 Population, Jared J. Schmidt, Melinda K. Yerka, Jeffrey F. Pedersen, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

Although sorghum [Sorghum bicolor (L.) Moench ssp. bicolor] is the fifth most important grain crop in terms of global production, no commercial hybrids carry genetically engineered (GE) traits for resistance to insect pests or herbicides due to regulatory concerns about gene flow to weedy relatives. However, non-GE herbicide resistance currently is being developed in grain sorghum and will likely transfer to related weeds. Monitoring the impact of this new nuclear technology on the evolution and invasiveness of related weeds requires a baseline understanding of the population biology of grain sorghum genes once they transfer to in situ weed …

Genomic Selection In Preliminary Yield Trials In A Winter Wheat Breeding Program, Vikas Belamkar, Mary J. Guttieri, Waseem Hussain, Diego Jarquin, Ibrahim El-Basyoni, Jesse Poland, Aaron J. Lorenz, P. Stephen Baenziger

Department of Agronomy and Horticulture: Faculty Publications

Genomic prediction (GP) is now routinely performed in crop plants to predict unobserved phenotypes. The use of predicted phenotypes to make selections is an active area of research. Here, we evaluate GP for predicting grain yield and compare genomic and phenotypic selection by tracking lines advanced. We examined four independent nurseries of F_3:6 and F_3:7 lines trialed at 6 to 10 locations each year. Yield was analyzed using mixed models that accounted for experimental design and spatial variations. Genotype-by-sequencing provided nearly 27,000 high-quality SNPs. Average genomic predictive ability, estimated for each year by randomly masking lines as missing …

Investigating The Ecology Of A Rare Species On St. John, Usvi: Reintroducing Solanum Conocarpum In Light Of Climate Change, Cecilia Rogers

Senior Honors Projects, 2010-2019

Approximately two thirds of St. John is National Park territory. However, the land has been threatened with tourism and development, greatly impacting island biodiversity. One species that may become extinct due to this degradation is Solanum conocarpum. S. conocarpum is a rare shrub, endemic to the dry tropical forests of St. John, USVI. This plant is a species of conservation concern and is one of very few native and endemic plants on this island. Very little is known about the ecology and reproduction of S. conocarpum. Most plants are found on the southern half of the island. Recent observations …

The Role Of Environmental Filtering In Structuring Appalachian Tree Communities: Topographic Influences On Functional Diversity Are Mediated Through Soil Characteristics, Julia I. Chapman, Ryan W. Mcewan

Biology Faculty Publications

Identifying the drivers of community assembly has long been a central goal in ecology, and the development of functional diversity indices has provided a new way of detecting the influence of environmental gradients on biotic communities. For an old-growth Appalachian forest, we used path analysis to understand how patterns of tree functional diversity relate to topography and soil gradients and to determine whether topographic effects are mediated through soil chemistry. All of our path models supported the idea of environmental filtering: stressful areas (high elevation, low soil moisture, low soil nutrients) were occupied by communities of low functional diversity, which …

Characterizing Low Nutrient Stress Resistance In Crop Sunflowers (Helianthus Annus), Casey Croshaw

All Master's Theses

Historically agriculture has met global food production demands, but abiotic stresses are predicted to decrease crop yield in the context of climate change. In order to prevent losses in crop yield under conditions of increasing environmental stress and to reduce environmental damage from unsustainable farming practices, improvements must be made in crop breeding and bioengineering. However, these improvements require insight into the mechanisms of abiotic stress resistance. In this study, 60 different genetic sunflower (Helianthus annuus) lines were grown in the field under fertilized and unfertilized treatments to assess phenotypic traits associated with low nutrient stress resistance. Sunflowers …

Tomato Spotted Wilt Virus Nss Protein Supports Infection And Systemic Movement Of A Potyvirus And Is A Symptom Determinant, Hernan Garcia-Ruiz, Sergio M. Gabriel Peralta, Patricia A. Harte-Maxwell

Department of Plant Pathology: Faculty Publications

Plant viruses are inducers and targets of antiviral RNA silencing. To condition susceptibility, most plant viruses encode silencing suppressor proteins that interfere with antiviral RNA silencing. The NSs protein is an RNA silencing suppressor in orthotospoviruses, such as the tomato spotted wilt virus (TSWV). The mechanism of RNA silencing suppression by NSs and its role in virus infection and movement are poorly understood. Here, we cloned and tagged TSWV NSs and expressed it from a GFP-tagged turnip mosaic virus (TuMV-GFP) carrying either a wild-type or suppressor-deficient (AS9) helper component proteinase (HC-Pro). When expressed in cis, NSs restored pathogenicity and promoted …

Intermolecular Rna Recombination Occurs At Different Frequencies In Alternate Forms Of Brome Mosaic Virus Rna Replication Compartments, Hernan Garcia-Ruiz, Arturo Diaz, Paul Ahlquist

Department of Plant Pathology: Faculty Publications

Positive-strand RNA viruses replicate their genomes in membrane-bound replication compartments. Brome mosaic virus (BMV) replicates in vesicular invaginations of the endoplasmic reticulum membrane. BMV has served as a productive model system to study processes like virus-host interactions, RNA replication and recombination. Here we present multiple lines of evidence showing that the structure of the viral RNA replication compartments plays a fundamental role and that recruitment of parental RNAs to a common replication compartment is a limiting step in intermolecular RNA recombination. We show that a previously defined requirement for an RNA recruitment element on both parental RNAs is not to …

Metagenomic Analysis Of Viruses Associated With Maize Lethal Necrosis In Kenya, Mwathi Jane Wamaitha, Deepti Nigam, Solomon Maina, Francesca Stomeo, Anne Wangai, Joyce Njoki Njuguna, Timothy A. Holton, Bramwel W. Wanjala, Mark Wamalwa, Tanui Lucas, Appolinaire Djikeng, Hernan Garcia Ruiz

Department of Plant Pathology: Faculty Publications

Background: Maize lethal necrosis is caused by a synergistic co-infection of Maize chlorotic mottle virus (MCMV) and a specific member of the Potyviridae, such as Sugarcane mosaic virus (SCMV), Wheat streak mosaic virus (WSMV) or Johnson grass mosaic virus (JGMV). Typical maize lethal necrosis symptoms include severe yellowing and leaf drying from the edges. In Kenya, we detected plants showing typical and atypical symptoms. Both groups of plants often tested negative for SCMV by ELISA. Methods: We used next-generation sequencing to identify viruses associated to maize lethal necrosis in Kenya through a metagenomics analysis. Symptomatic and asymptomatic leaf samples …

Susceptibility Genes To Plant Viruses, Hernan Garcia Ruiz

Department of Plant Pathology: Faculty Publications

Plant viruses use cellular factors and resources to replicate and move. Plants respond to viral infection by several mechanisms, including innate immunity, autophagy, and gene silencing, that viruses must evade or suppress. Thus, the establishment of infection is genetically determined by the availability of host factors necessary for virus replication and movement and by the balance between plant defense and viral suppression of defense responses. Host factors may have antiviral or proviral activities. Proviral factors condition susceptibility to viruses by participating in processes essential to the virus. Here, we review current advances in the identification and characterization of host factors …

Profile Of Genetically Modified Plants Authorized In Mexico, Mayra Teresa Garcia Ruiz, Aaron N. Knapp, Hernan Garcia Ruiz

Department of Plant Pathology: Faculty Publications

Mexico is a center of origin for several economically important plants including maize, cotton, and cocoa. Maize represents more than a food crop, has been declared a biological, cultural, agricultural and economic patrimony, and is linked to the national identity of Mexicans. In this review, we describe the historic and current use of genetically modified plants in Mexico and factors that contributed to the development of the biosafety regulation. We developed a database containing all permit applications received by the government to release genetically modified plants. A temporal and geographical analysis identified the plant species that have been authorized for …

Primula Veris Plants Derived From In Vitro Cultures And From Seeds: Genetic Stability, Morphology, And Seed Characteristics, Iwona Jedrzejczyk, Maria Morozowska, Renata Nowinska, Andrzej Jagodzinski

Turkish Journal of Botany

Flow cytometry measurement confirmed the genetic stability of Primula veris L. (cowslip) plants obtained during the micropropagation process. The mean 2C DNA content was 0.97 pg/2C and P. veris can be classified in the group of plants of very small genomes. Comparative morphological analysis of cowslip plants regenerated in vitro and derived from seeds was carried out in three subsequent years under common garden conditions, which limited the effects of environmental factors. The origin of specimens significantly influenced most of the morphological traits examined. Plants that originated from seeds were characterized by more intensive development rate and higher total seed …

Callus Production And Analysis Of Some Secondary Metabolites In Globularia Trichosantha Subsp. Trichosantha, Hati̇ce Çölgeçen, Havva Atar, Gülnur Toker, Gençay Akgül

Turkish Journal of Botany

This study describes the production of calli from Globularia trichosantha subsp. trichosantha and the quantitative determination of catalpol, aucubin, and verbascoside in the calli and the plant by HPLC. The seeds of the plant were sterilized and germinated in Murashige and Skoog (MS) medium without in vitro plant growth regulator. Hypocotyl, cotyledon, first leaf, epicotyl, apical meristem, and root explants were taken from the 30-day-old aseptic seedlings germinated in vitro. Explants were then transferred to MS media for callus production together with varying concentrations of plant growth regulators. The best callus production occurred in the media containing 6 mg L?1 …

Genomic-Enabled Prediction Models Using Multi-Environment Trials To Estimate The Effect Of Genotype × Environment Interaction On Prediction Accuracy In Chickpea, Manish Roorkiwal, Diego Jarquin, Muneendra K. Singh, Pooran M. Gaur, Chellapilla Bharadwaj, Abhishek Rathore, Reka Howard, Samineni Srinivasan, Ankit Jain, Vanika Garg, Sandip Kale, Annapurna Chitikineni, Shailesh Tripathi, Elizabeth Jones, Kelly R. Robbins, José Crossa, Rajeev K. Varshney

Department of Agronomy and Horticulture: Faculty Publications

Genomic selection (GS) by selecting lines prior to field phenotyping using genotyping data has the potential to enhance the rate of genetic gains. Genotype × environment (G × E) interaction inclusion in GS models can improve prediction accuracy hence aid in selection of lines across target environments. Phenotypic data on 320 chickpea breeding lines for eight traits for three seasons at two locations were recorded. These lines were genotyped using DArTseq (1.6 K SNPs) and Genotyping-by-Sequencing (GBS; 89 K SNPs). Thirteen models were fitted including main effects of environment and lines, markers, and/or naïve and informed interactions to estimate prediction …

Gene Expression Profiling Of Iron Deficiency Chlorosis Sensitive And Tolerant Soybean Indicates Key Roles For Phenylpropanoids Under Alkalinity Stress, Brian M. Waters, Keenan Amundsen, George L. Graef

Department of Agronomy and Horticulture: Faculty Publications

Alkaline soils comprise 30% of the earth and have low plant-available iron (Fe) concentration, and can cause iron deficiency chlorosis (IDC). IDC causes soybean yield losses of $260 million annually. However, it is not known whether molecular responses to IDC are equivalent to responses to low iron supply. IDC tolerant and sensitive soybean lines provide a contrast to identify specific factors associated with IDC.We used RNA-seq to compare gene expression under combinations of normal pH (5.7) or alkaline pH (7.7, imposed by 2.5mM bicarbonate, or pH 8.2 imposed by 5mM bicarbonate) and normal (25μM) or low (1μM) iron conditions from …