Life Sciences Commons^™

Pollen-Mediated Gene Flow From Genetically Modified Herbicide Resistant Creeping Bentgrass, L. S. Watrud, E. H. Lee, A. Fairbrother, C. Burdick, J. R. Reichman, M. Bollman, M. Storm, G. King, P. K. Van De Water

IGC Proceedings (1997-2023)

Approximately 162 ha of multiple experimental fields of creeping bentgrass (Agrostis stolonifera L.) genetically modified for resistance to Roundup ®herbicide, were planted in central Oregon in 2002. When the fields flowered for the first time in the summer of 2003, a unique opportunity was presented to evaluate methods to monitor potential pollen-mediated gene flow from the experimental GM crop fields to compatible sentinel and resident plants that were located in surrounding, primarily non-agronomic areas.

Distribution And Genomic Diversity Of Pollen-Borne Viruses And Viroids At The Interface Of Peach And Wild Prunus Spp. In The Southeastern United States, Fabian Omar Rodriguez Bonilla

All Theses

Prunus necrotic ringspot virus (PNRSV), prune dwarf virus (PDV), and peach latent mosaic viroid (PLMVd) are important pollen-borne pathogens that affect peach orchards in the southeastern United States. My aim with this research is to identify potential sources of virus/viroid inoculum sources in the wild and determine pathogen movement and interactions between wild Prunus spp. and cultivars of peach (P. persica). In Chapter I, I review the literature on pollen borne viruses and viroids in peach. In Chapter II, I surveyed for these pathogens near peach production areas in South Carolina and Georgia, sampling from three endemic wild …

The Effects Of Ppal-1 In Arabidopsis Gamete Development, Amanda J White, Susana Perez-Martinez, Mark P. Running

The Cardinal Edge

Prenylation is a type of post-translational modification in which a 15- or 20-carbon lipid is added to the carboxyl (C) terminus of the protein. Arabidopsis thaliana contains the PROTEIN PRENYLTRANSFERASE ALPHA SUBUNIT-LIKE (PPAL) gene, which encodes a protein with homology to the α-subunits of the three known prenylation enzymes, PFT, PGGT, and Rab-GGT. We previously identified two mutations in PPAL, one of which is ppal-1, which contains a T-DNA insertion in the fourth intron. We have previously observed that self-fertilizing heterozygous ppal-1 plants produce progeny in which homozygous ppal-1 is underrepresented. This project attempts to ascertain …

Study On The Pollen Morphologies And Seed Setting Rate Of Hemarthria Compressa, Xiantao Fu, Chunhua Yang, Lingzhi Chen, Xinquan Zhang, Ke Ma

IGC Proceedings (1997-2023)

No abstract provided.

A New Asperula L. (Rubiaceae) Species From Gypsum Steppes Of Çankırı Province In Turkey, Bi̇lal Şahi̇n, Mehmet Sağiroğlu, Bi̇rol Başer

Turkish Journal of Botany

Asperula cankiriense B.Şahin & Sağıroğlu, a new species discovered in the central Anatolian region of Turkey (Çankırı), is described herein. A. cankiriense is similar to Asperula bornmuelleri Velen. However, A. cankiriense differs mainly in its habitus, stem, leaves, and inflorescence features. In this study, the diagnostic morphological features, distribution, habitat and ecology, etymology, conservation status, and taxonomic features of the new species are discussed. Additionally, pollen micromorphological characteristics of A. cankiriense and A. bornmuelleri are examined and compared using light microscopy (LM) and scanning electron microscopy (SEM) analyses. The pollen grains are subprolate, aperture type 6?7 or rarely 8 zonocolpate …

Taxonomic Monograph Of The Tribe Nigelleae (Ranunculaceae): A Group Including Ancientmedicinal Plants, Ali̇ Aslan Dönmez, Zübeyde Uğurlu Aydin, Emel Oybak Dönmez

Turkish Journal of Botany

The tribe Nigelleae Schröd. (Ranunculaceae) worldwide distribution has been studied taxonomically, based on morphological, palynological and seed morphological characters, as well as chromosome counts. Extensive field works have been carried out in Turkey, Greece, Iran, Syria, Lebanon, Portugal and in Northern Cyprus. Moreover, the specimens of major herbaria in Turkey, Ukraine, Russia, Syria and Iran as well in Europe have been examined. This study represents the most comprehensive monograph of the tribe based on field work across its nearly entire distributional range, complemented by examination of over 980 specimens from 25 herbaria and our collections with nomenclatural contributions. Eighteen species …

Arp2/3-Independent Wave/Scar Pathway And Class Xi Myosin Control Sperm Nuclear Migration In Flowering Plants, Mohammad F. Ali, Umma Fatema, Xiongbo Peng, Samuel W. Hacker, Daisuke Maruyama, Meng-Xiang Sun, Tomokazu Kawashima

Plant and Soil Sciences Faculty Publications

After eukaryotic fertilization, gamete nuclei migrate to fuse parental genomes in order to initiate development of the next generation. In most animals, microtubules control female and male pronuclear migration in the zygote. Flowering plants, on the other hand, have evolved actin filament (F-actin)-based sperm nuclear migration systems for karyogamy. Flowering plants have also evolved a unique double-fertilization process: two female gametophytic cells, the egg and central cells, are each fertilized by a sperm cell. The molecular and cellular mechanisms of how flowering plants utilize and control F-actin for double-fertilization events are largely unknown. Using confocal microscopy live-cell imaging with a …

Reproductive Ecology And Phenology Of Thalassia Testudinum (Hydrocharitaceae) In Tampa Bay, Florida, Sheila Scolaro

USF Tampa Graduate Theses and Dissertations

Successful sexual reproduction and recolonization are critical in maintaining genetic diversity within seagrass meadows. Thalassia testudinum flower, fruit and seedling production were assessed visually at 10 sites within Tampa Bay, Florida approximately every 4 weeks from May to July 2017 to determine if there is spatial and temporal variation in sexual reproductive effort and if location within a meadow effects sexual reproductive effort. Results from this study reveal strong temporal variability throughout the reproductive season. The month of May was observed as peak Thalassia testudinum anthesis and June was peak fruiting in Tampa Bay during 2017. Flower and fruit density …

Sequenced-Based Paternity Analysis To Improve Breeding And Identify Self-Incompatibility Loci In Intermediate Wheatgrass (Thinopyrum Intermedium), Jared Crain, Steve Larson, Kevin Dorn, Traci Hagedorn, Lee Dehaan, Jesse Poland

Forage and Range Research Laboratory Publications

Key Message

Paternity assignment and genome-wide association analyses for fertility were applied to a Thinopyrum intermedium breeding program. A lack of progeny between combinations of parents was associated with loci near self-incompatibility genes.

Abstract

In outcrossing species such as intermediate wheatgrass (IWG, Thinopyrum intermedium), polycrossing is often used to generate novel recombinants through each cycle of selection, but it cannot track pollen-parent pedigrees and it is unknown how self-incompatibility (SI) genes may limit the number of unique crosses obtained. This study investigated the potential of using next-generation sequencing to assign paternity and identify putative SI loci in IWG. Using …

Method Development For Identifying Counterfeit Cigarettes Using Environmental Pollen Analysis, Tiffany Chan

Student Theses

Cigarette counterfeiting negatively impacts government revenue and undermines tobacco control policies. Tracking geographical origins and potential trade routes of counterfeit cigarettes is important for investigation illegal trade in tobacco products. Traditional pollen extraction techniques provide clear residues of pollen trapped on tobacco leaves and used for geographical identification; however, such methods are time-consuming and utilize concentrated chemicals. This study developed a simple, fast and environmentally friendly method for extraction of pollen grains used in differentiating genuine and counterfeit cigarettes. Experimental factors that may affect pollen recovery including number of cigarettes, extraction solution, and extraction temperature, were optimized. The optimum parameters …

Holocene Fire History Reconstruction Of A Mid-Evaluation Mixed-Conifer Forest In The Eastern Cascades, Washington, Zoe Rushton

All Master's Theses

Fire histories of mid-elevation mixed-conifer forests (MEMC) are uncommon, particularly in the eastern Cascades of Washington. As a result, fire regimes and the effects of 20th century fire suppression in these forests are not well understood. In the summer of 2014 a 7.80 meter-long sediment core was extracted from Long Lake, located approximately 45 km west of Yakima, WA, which exists in a grand fir-dominated mixed-conifer forest. Fire activity for the Long Lake watershed was reconstructed using macroscopic charcoal analysis and pollen analysis was used to reconstruct vegetation change through time. Charcoal results show low fire activity in the early …

Biology Of Flowering And Insect Visitors Of Iris Aphylla L. (Iridaceae), Agnieszka Dabrowska, Magdalena Smigala, Bozena Denisow, Krystyna Winiarczyk

Turkish Journal of Botany

The paper presents the morphology of the flower of Iris aphylla L., which is a protected species in many European countries. The study comprises phenological observations of flowering and assessment of nectar and pollen production, and flowering and fruiting abundance. Additionally, the number of insect visitors on the flowers was monitored. The investigations of specimens originating from 4 populations in central-eastern Poland (Wyzyna Lubelska Upland) were conducted in the Botanical Garden of Maria Curie-Sklodowska University. It was found that morphological features of the analysed flowers, i.e. the 6-angular ovary and the perianth tube, which is 2-fold longer than the ovary, …

Plants, Parasites, And Pollinators: The Effects Of Medicinal Pollens On A Common Gut Parasite In Bumble Bees, George Locascio

Masters Theses

Declines in several pollinator species are due to a variety of factors, including pathogens. Incorporating pollinator-friendly plant species into wild and agricultural habitats could reduce the stress of pathogens if food sources act medicinally against pathogens. Previous research demonstrated one domesticated sunflower cultivar (Helianthus annuus) can dramatically reduce a gut pathogen (Crithidia bombi) of the common eastern bumble bee, Bombus impatiens. To ascertain the breadth of this medicinal trait, we tested whether pollen from several H. annuus cultivars and four relatives could also reduce C. bombi infections in B. impatiens. We also investigated whether …

Flower Visitation In Relation To Pollen And Nectar Nutrition: Implications For Pollinator Habitat And Conservation, Megan E. Leach

Electronic Theses and Dissertations

Pollination of both wild and crop plants is at a crossroads; honey bee populations are experiencing losses at a higher rate than ever before, and some native bee species are declining in abundance to the point of being listed as endangered species. A few examples of these threats include pesticide exposure, habitat loss, and climate change. In response to bee population declines, conservation efforts have been initiated to increase habitat quality for bees by planting pollinator reservoirs or gardens. Plants provide nutrition to bees in the form of pollen and nectar. Several studies have shown links between higher nutritional quality …

Systematics Value Of Micromorphological And Palynological Characters In Stenocephalum Sch.Bip. (Vernonieae, Asteraceae), Maria Betiana Angulo, Laura Chalup, Massimiliano Dematteis

Turkish Journal of Botany

Micromorphological and palynological characters of all Stenocephalum Sch.Bip. species (Vernonieae, Asteraceae) were analyzed to evaluate their reliability as taxonomic markers at generic level and discussed in relation to other genera of the subtribe Lepidaploinae. Characters such as pubescence of corollas and cypselae showed glandular and nonglandular trichomes allowing differentiation among related species. Apical appendages without glandular trichomes, caudate anthers, and carpopodium structure are common characteristics among Stenocephalum species. With the exceptions of S. megapotamicum and S. tragiaefolium, almost all species of the genus showed style bases without basal nodes for the first time. Crystals on the fruits wall were also …

Protocol For Enrichment Of The Membrane Proteome Of Mature Tomato Pollen, Puneet Paul, Palak Chaturvedi, Anida Mesihovic, Arindam Ghatak, Wolfram Weckwerth, Enrico Schleiff

Department of Agronomy and Horticulture: Faculty Publications

We established and elaborated on a method to enrich the membrane proteome of mature pollen from economically relevant crop using the example of Solanum lycopersicum (tomato). To isolate the pollen protein fraction enriched in membrane proteins, a high salt concentration (750 mM of sodium chloride) was used. The membrane protein-enriched fraction was then subjected to shotgun proteomics for identification of proteins, followed by in silico analysis to annotate and classify the detected proteins.

The Effect Of Insects On Seed Set Of Ozark Chinquapin, Castanea Ozarkensis, Colton Zirkle

Graduate Theses and Dissertations

Ozark chinquapin (Castanea ozarkensis), once found throughout the Interior Highlands of the United States, has been decimated across much of its range due to accidental introduction of chestnut blight, Cryphonectria parasitica. Efforts have been made to conserve and restore C. ozarkensis, but success requires thorough knowledge of the reproductive biology of the species. Other Castanea species are reported to have characteristics of both wind and insect pollination, but pollination strategies of Ozark chinquapin are unknown. Experiments were conducted to determine the influence of insects on successful pollination of C. ozarkensis, as measured by production of burs and seeds. Exclosure treatments …

Foraging Behavior Of Spring Bees And Their Agricultural Implications, Michael D. Gregory

Biological Sciences Theses & Dissertations

Colony Collapse Disorder has greatly reduced honey bee populations in the last decade. Native bees have been largely neglected in research, and their floral preferences may have agricultural implications because native bees ameliorate the demand to rely solely on non-native bees. In this work, pollinator visitation to flowers with manipulated ultraviolet floral patterns was monitored. Populations of wild showy golden-eye in Colorado, plus cultivar populations of black-eyed Susan and lawn populations of buttercups in Virginia were monitored for pollinator landings to compare preference for unmanipulated ultraviolet-absorptive floral guide preferences. Another number, a proxy for pollen load, was manipulated on strawberry …

A Taxonomic Study Of The Silene Sections Behenantha And Dichotomae (Caryophyllaceae) In Turkey Based On The Micromorphology Of Their Seed And Pollen, Mehmet Kuh, Kemal Yildiz, Ersi̇n Mi̇nareci̇

Turkish Journal of Botany

The seed and pollen grain micromorphologies of 10 taxa of the Silene sections Behenantha and Dichotomae (Caryophyllaceae) were analyzed in this study. Although the seeds of the analyzed taxa were generally reniform, S. tenuiflora and S. koycegizensis from the section Behenantha were clearly distinct from other taxa, while subspecies of S. dichotoma and S. euxina in the section Dichotomae showed differences. Pollen grains are periporate and spheroidal and ornamentation is generally spinulate-microperforate in all taxa. However, ornamentation is spinulate in S. euxina and semireticulate in S. koycegizensis. While the exine structure is generally tectate, it is semitectate in S. koycegizensis. …

Muts Homolog1 Silencing Mediates Orf220 Substoichiometric Shifting And Causes Male Sterility In Brassica Juncea, Na Zhao, Xinyue Xu, Yashitola Wamboldt, Sally Ann Mackenzie, Xiaodong Yang, Zhongyuan Hu, Jinghua Yang, Mingfang Zhang

Department of Agronomy and Horticulture: Faculty Publications

Cytoplasmic male sterility (CMS) has consistently been associated with the expression of mitochondrial open reading frames (ORFs) that arise from genomic rearrangements. Spontaneous fertility reversion in CMS has been observed in several cases, but a clear understanding of fertility reversion controlled by nuclear genetic influences has been lacking. Here, we identified spontaneous fertile revertant lines for Brassica juncea CMS cytoplasm in which the mitochondrial genome has undergone substoichiometric shifting (SSS) to suppress ORF220 copy number. We placed ORF220, with or without a mitochondrial targeting presequence, under the control of the CaMV35S and AP3 promoters in Arabidopsis to confirm that ORF220 …

A New Species Of Plectranthus (Lamiaceae) From Saudi Arabia, Kadry Abdel Khalik

Turkish Journal of Botany

Plectranthus hijazensis Abdel Khalik (Lamiaceae) is described as a new species from Al-Baha Province in Saudi Arabia. Information given on the new species includes a taxonomic description and its affinity to Plectranthus asirensis L. A key to Plectranthus species of Saudi Arabia is provided, and the relationships of the species and the relevant morphological characters, particularly seed, pollen grains, trichomes, and anatomy of stem and leaf, are discussed. A distribution map of the new species and related species is provided.

Mechanosensitive Channel Msl8 Regulates Osmotic Forces During Pollen Hydration And Germination, Eric S. Hamilton, Gregory S. Jensen, Grigory Maksaev, Andrew Katims, Ashley M. Sherp, Elizabeth S. Haswell

Biology Faculty Publications & Presentations

Pollen grains undergo dramatic changes in cellular water potential as they deliver the male germ line to female gametes, and it has been proposed that mechanosensitive ion channels may sense the resulting mechanical stress. Here, we identify and characterize MscS-like 8 (MSL8), a pollen-specific, membrane tension–gated ion channel required for pollen to survive the hypoosmotic shock of rehydration and for full male fertility. MSL8 negatively regulates pollen germination but is required for cellular integrity during germination and tube growth. MSL8 thus senses and responds to changes in membrane tension associated with pollen hydration and germination. These data further suggest that …

Pore Selectivity And Gating Of Arabidopsis Nodulin 26 Intrinsic Proteins And Roles In Boric Acid Transport In Reproductive Growth, Tian Li

Doctoral Dissertations

Plant nodulin-26 intrinsic proteins (NIPs) are members of the aquaporin superfamily that serve as multifunctional channels of uncharged metabolites and water. They share the same canonical hourglass fold as the aquaporin family. The aromatic arginine (ar/R) selectivity filter controls transport selectivity based on size, hydrophobicity, and hydrogen bonding with substrates. In Arabidopsis thaliana, NIP II subclass proteins contain a conserved ar/R “pore signature” that is composed of Alanine at the helix 2 position (H2), Valine/Isoleucine at the helix 5 position (H5), and an Alanine (LE1) and an invariant Arginine (LE2) at the two loop E positions. In this study, …

The Movement Ecology Of Seagrasses, Kathryn Mcmahon, Kor-Jent Van Dijk, Leonardo Ruiz-Montoya, Gary A. Kendrick, Siegfried L. Krauss, Michelle Waycott, Jennifer Verduin, Ryan Lowe, John Statton, Eloise Brown, Carlos Duarte

Research outputs 2014 to 2021

A movement ecology framework is applied to enhance our understanding of the causes, mechanisms and consequences of movement in seagrasses: marine, clonal, flowering plants. Four life-history stages of seagrasses can move: pollen, sexual propagules, vegetative fragments and the spread of individuals through clonal growth. Movement occurs on the water surface, in the water column, on or in the sediment, via animal vectors and through spreading clones. A capacity for long-distance dispersal and demographic connectivity over multiple timeframes is the novel feature of the movement ecology of seagrasses with significant evolutionary and ecological consequences. The space–time movement footprint of different life-history …

Pollen Biology, Alice Cheung, Hen-Ming Wu

Science and Engineering Saturday Seminars

No abstract provided.

Airborne Pollen Content Of Kuşadası, Aycan Tosunoğlu, Ayşe Yeni̇gün, Adem Biçakçi, Kayi Eli̇açik

Turkish Journal of Botany

Atmospheric pollen grains of Kuşadası were captured using Durham samplers and investigated in 2005. The total number of pollen grains and the pollen grains/cm^2 were calculated from slides that were changed weekly. During the study period a total of 12,980 pollen grains/cm^2 belonging to 44 identified taxa and unidentified pollen grains were recorded at 2 stations. At the first station (S1), 7346 pollen grains were counted per cm^2, while only 5634 pollen grains were counted at the second station (S2). The majority of the investigated pollen grains were from Olea europaea L. (34.46%), Cupressaceae/Taxaceae (30.04%), Pinus spp. (19.71%), Platanus spp. …

Pollen Morphology Of The Genus Onobrychis (Fabaceae) In Turkey, Süleyman Avci, Cengi̇z Sancak, Alp Can, Aydan Acar, Nur Münevver Pinar

Turkish Journal of Botany

The pollen size and morphology of 20 Onobrychis Adans. taxa from Turkey were studied using both light and scanning electron microscopy. Of the taxa studied, Onobrychis fallax Freyn & Sint. and Onobrychis elata Boiss. & Balansa showed the smallest size of pollen grains, while the largest were found in Onobrychis aequidentata (Sibth. & Sm.) d'Urv. and Onobrychis viciifolia Scop. The pollens of all taxa studied represent the tricolpate type of pollen and are prolate in shape. The type of exine found in the studied taxa is reticulate (sect. Dendobrychis DC. and sect. Laphobrychis Hand.-Mazz.), suprareticulate (sect. Onobrychis), or microreticulate (sect. …

Pollen And Seed Morphology Of Resurrection Plants From The Genus Ramonda (Gesneriaceae): Relationship With Ploidy Level And Relevance To Their Ecology And Identification, Maja Lazarevic, Sonja Siljak - Yakovlev, Predrag Lazarevic, Branka Stevanovic, Vladimir Stevanovic

Turkish Journal of Botany

The pollen and seeds of 3 paleoendemic resurrection species, Ramonda myconi (L.) Rchb. (Iberian Peninsula), R. nathaliae Pancic & Petrovic, and R. serbica Pancic (Balkan Peninsula), as well as of natural hybrids between the 2 last species, have been analyzed using light and scanning electron microscopy. Their general structural differences, taxonomic and phylogenetic significance, pollen viability, and seed germination capacity, as well as the correlation of pollen and seed characteristics and plant ploidy levels, have been studied. The pollen grains are small (R. myconi, R. nathaliae) to medium (R. serbica) in size, ranging from 10 to 28 µm, and 3-colporate, …

A Comparative Analysis Of The Relative Water Content Of The Pollen Of Early Diverging Angiosperms, Andrew Robert Moffatt

Chancellor’s Honors Program Projects

No abstract provided.

Rugaspermum Minuta - A New Species Of The Seed Genus Rugaspermum From The Triassic Of Nidpur, India, Nupur Bhowmik, Shabnam Parveen

Turkish Journal of Botany

This paper provides a description of a new species of Rugaspermum D.D.Pant & Basu, R. minuta Bhowmik & Parveen, from the Nidpur Triassic beds. The dispersed seeds were recovered after macerating large chunks of shale in hydrofluoric acid. The structurally preserved compressed seed is platyspermic, orthotropus, and oval- to barrel-shaped with a short beak-like micropyle. The surfaces of the seeds are wrinkled and there is a wide lateral ridge running from the apex to the base on both the obverse and reverse sides. Upon maceration, the seed yielded 4 membranes: outer, inner, nucellar, and megaspore membranes. The outer cuticle of …