Biology Commons^™

More Evidence That Mutation Rate In The Chloroplast Genome Depends On Copy Number, Ashley Dutton

Undergraduate Honors Theses

The conservative nature of the copy variable region (CVR) of the chloroplast genome, also known as the inverted repeat (IR) region, is well established; however the basis for the lower mutation rate has been debated. Two ideas have been proposed to explain the reduced rate: 1) genes in the region are inherently slow to evolve; or 2) the presence of two copies reduces the rate via copy correction. Comparisons of eighty-three genes and twenty introns were made estimating mutation rates, from both the CVR region and single copy (SC) regions in legumes and gymnosperms. In gene and intron comparisons, CVR …

Mojave Applied Ecology Notes Winter 2008, Scott R. Abella, E. Cayenne Engel, Jill E. Craig

Mojave Applied Ecology Notes

Mojave Desert collaborative projects, fire history in Spring Mountains, Northshore Road rehabilitation, wildfires and invasive plants in American deserts conference, weed sentry surveys

Insertion Of The Enzyme Cyclopropane Fatty Acid Synthase Into Plastids Through Agrobacterium Mediated Transformation, Jason L. Rush

Undergraduate Honors Thesis Collection

Under natural conditions, Agrobacterium is a plant pathogen that infects plants by inserting genes into the plant's genome that are desirable to the bacterium itself. A tumor is then formed and the infected plant tissue makes molecules that the bacterium uses as food.

Investigation Of Kalanchoe Homeobox 1 (Kh1) Gene In Apical Meristems Of Kalanchoe Pinnatum, Jessica Lynn Kirkpatrick

Undergraduate Honors Thesis Collection

Kalanchoe pinnatum (syn. Bryophyllum pinnatum) is a succulent plant that is notable for developing small plantlets on the outer edges of its leaves, when its leaves are detached (Kulka 2006). These plantlets eventually drop off and root, which is a unique way for the plant to asexually reproduce. In most other plants, leaves exhibit determinate growth, meaning once they reach their maturity, they do not continue to grow.

Comparative Biology Of Seed Dormancy-Break And Germination In Convolvulaceae (Asterids, Solanales), Kariyawasam Marthinna Gamage Gehan Jayasuriya

University of Kentucky Doctoral Dissertations

The biology of seed dormancy and germination of 46 species representing 11 of the 12 tribes in Convolvulaceae were compared in laboratory (mostly), field and greenhouse experiments. Seeds were tested for kind of dormancy and storage behavior; artificial or simulated natural treatments were applied to break physical dormancy (PY); the initial route of water entry (“water gap”) into seeds was identified; the morphoanatomy of the water gap was compared in seeds of 17 species; ontogenetical differences between water gap and seed coat away from the hilum were described in Ipomoea lacunosa seeds; cycling of sensitivity to dormancy break was elucidated …

Sporophytic Inbreeding Depression In Mosses Occurs In A Species With Separate Sexes But Not In A Species With Combined Sexes, Philip J. Taylor, Sarah M. Eppley, Linley K. Jesson

Biology Faculty Publications and Presentations

Inbreeding depression is a critical factor countering the evolution of inbreeding and thus potentially shaping the evolution of plant sexual systems. Current theory predicts that inbreeding depression could have important evolutionary consequences, even in haploid-dominant organisms. To date, no data have been reported on inbreeding depression in moss species. Here, we present data on the magnitude of inbreeding depression in sporophytic traits of moss species with contrasting breeding systems. In eratodon purpureus (Ditrichaceae), a moss species with separate sexes, self-fertilizations between sibling gametophytes (intergametophytic selfing) significantly reduced fitness in two of four traits quantified, with seta length and capsule length …

The Potential Role Of Probiotics In Reducing Poverty-Associated Infections In Developing Countries, Kingsley Anukam

Data and Test Instruments

Probiotics are defined by the Food and Agricultural Organization/ World Health Organization as “live microorganisms which when administered in adequate amounts confer a health benefit on the host” [1]. The potential benefits of their use have not been adequately investigated, especially in the developing world. Japan introduced Yakult, a probiotic fermented food drink in 1935, and in the Northern hemisphere, research and use of probiotics has gained an unprecedented momentum in the last decade [2]. Use of probiotics is not uncommon in Europe [3], but in many developing countries use of probiotics in its present definition is a foreign concept. …

Heritability Of Latent Period Estimated From Wild-Type And Selected Populations Of Puccinia Triticina, Jeffery S. Lehman, Gregory Shaner

Biology and Earth Science Faculty Scholarship

Durability of partially resistant wheat cultivars to wheat leaf rust depends on the amount of genetic variation in parasitic fitness within populations of the pathogen Puccinia triticina. To assess the durability of partial resistance, selection experiments were used to explore quantitative variation in parasitic fitness of P. triticina. Fungal populations 881-WT and 882-WT were selected for shortened latent period on partially resistant cvs. CI 13277 and Sw 72469-6 for multiple generations. Fitness components were measured for wild-type and selected fungal populations. Responses to selection and selection differentials were calculated, and broad-sense, realized heritabilities for latent period were estimated for wild-type …

Host Resistance To Monilinia Vaccinii-Corymbosi In Flowers And Fruits Of Highbush Blueberry, Jeffery S. Lehman, Suzu Igarashi, Peter V. Oudemans

Biology and Earth Science Faculty Scholarship

Monilinia vaccinii-corymbosi, the causal agent of mummy berry disease, infects blueberry flowers via the gynoecial pathway. To describe the expression of host resistance in highbush blueberry (Vaccinium corymbosum), fungal growth in the styles and colonization of the locules were compared among five blueberry cultivars in a series of controlled greenhouse experiments. Styles were harvested 1 and 4 days postinoculation, and the length colonized by hyphae was determined using fluorescence microscopy. At 8 weeks after inoculation, fruit were harvested and scored for the presence of hyphae in the locules. The infection frequency of styles ranged from 0.33 to 0.71, and only …

Comparative Chloroplast Genomics: Analyses Including New Sequences From The Angiosperms Nuphar Advena And Ranunculus Macranthus, Linda A. Raubeson, Rhiannon Peery, Timothy W. Chumley, Chris Dziubek, H. Matthew Fourcade, Jeffrey L. Boore, Robert K. Jansen

All Faculty Scholarship for the College of the Sciences

Background

The number of completely sequenced plastid genomes available is growing rapidly. This array of sequences presents new opportunities to perform comparative analyses. In comparative studies, it is often useful to compare across wide phylogenetic spans and, within angiosperms, to include representatives from basally diverging lineages such as the genomes reported here: Nuphar advena (from a basal-most lineage) and Ranunculus macranthus (a basal eudicot). We report these two new plastid genome sequences and make comparisons (within angiosperms, seed plants, or all photosynthetic lineages) to evaluate features such as the status of ycf15 and ycf68 as protein coding genes, the distribution …

Identification And Control Of Pest Slugs And Snails For Broadacre Crops In Western Australia, Svetlana Micic, Ken Henry, Paul Horne

Bulletins 4000 -

The numbers of slugs and snails have increased in broadacre cropping in Western Australia with the use of minimum tillage and stubble-retention practices. The organic content of paddocks increases under such systems, providing an increased food source especially to young slugs and snails. Soil moisture content is greater over summer leading to higher survival levels of slugs and snails.

Slug and snail pests in Australia have come from other countries, mainly the Mediterranean region. They damage plant seeds (mainly legumes), recently germinated seeds, seedlings and leaves and can be a contaminant of grain at harvest.

Invasion By Aegilops Triuncialis (Barb Goatgrass) Slows Carbon And Nutrient Cycling In A Serpentine Grassland, Rebecca E. Drenovsky, Katharine M. Batton

Biology

Invasive plant species alter plant community composition and ecosystem function. In the United States, California native grasslands have been displaced almost completely by invasive annual grasses, with serpentine grasslands being one of the few remaining refugia for California grasslands. This study examined how the invasive annual grass, Aegilops triuncialis, has altered decomposition processes in a serpentine annual grassland. Our objectives were to (1) assess howA. triuncialis alters primary productivity and litter tissue chemistry, (2) determine whether A. triuncialis litter is more recalcitrant to decomposition than native litter, and (3) evaluate whether differences in the soil microbial community in A. triuncialis-invaded …

Mid-Spring Burning Reduces Spotted Knapweed And Increases Native Grasses During A Michigan Experimental Grassland Establishment, Neil W. Macdonald, Brian T. Scull, Scott R. Abella

Peer Reviewed Publications

The definitive version is available at www.blackwell-synergy.com Infestations of the exotic perennial Spotted knapweed (Centaurea maculosa Lam.) hinder the restoration and management of native ecosystems on droughty, infertile sites throughout the Midwestern United States. We studied the effects of annual burning on knapweed persistence on degraded, knapweed-infested gravel-mine spoils in western Michigan. Our experiment included 48, 4-m² plots seeded to native warm-season grasses in 1999 using a factorial arrangement of initial herbicide and fertility treatments. Beginning in 2003, we incorporated fire as an additional factor and burned half of the plots in late April or May for three …

Ips Pini (Curculionidae: Scolytinae) Is A Vector Of The Fungal Pathogen, Sphaeropsis Sapinea (Coelomycetes), To Austrian Pines, Pinus Nigra (Pinaceae), Justin G.A. Whitehall, Jeffery S. Lehman, Pierluigi Bonello

Biology and Earth Science Faculty Scholarship

Sphaeropsis sapinea (Fr.:Fr.) Dyko and Sutton, is among the most common and widely distributed pathogens of conifers worldwide. S. sapinea is disseminated over short distances by rain splash and moist wind, but significant knowledge gaps regarding long-range dispersal remain. Our objective was to determine whether or not the pine engraver beetle, Ips pini Say, is a vector of the pathogen onto Austrian pines (Pinus nigra Arnold). In 2004 and 2005, individuals of I. pini were collected with pheromone traps at two locations in central Ohio (197 and 1,017 individuals for 2004 and 2005, respectively) and screened for the presence of …

Conservation Of B Class Gene Expression In The Second Whorl Of A Basal Grass And Outgroups Links The Origin Of Lodicules And Petals, Clinton Whipple, Michael Zanis, Elizabeth Kellogg, Robert Schmidt

Biology Department Faculty Works

Studies of flower development in core eudicot species have established a central role for B class MADS-box genes in specifying petal and stamen identities. Similarly in maize and rice, B class genes are essential for lodicule and stamen specification, suggesting homology of petals and lodicules and conservation of B class gene activity across angiosperms. However, lodicules are grass-specific organs with a morphology distinct from petals, thus their true homology to eudicot and nongrass monocot floral organs has been a topic of debate. To understand the relationship of lodicules to the sterile floral organs of nongrass monocots we have isolated and …

Native And Exotic Plant Species Exhibit Similar Population Dynamics During Succession, Scott Meiners

Faculty Research & Creative Activity

A growing body of literature has led to the debate in invasion biology whether exotic species perform within communities differently than native taxa due to inherent advantages. To address this issue, the population dynamics of native and exotic plant species were assessed from a 48-year record of permanent plot data from the Hutcheson Memorial Forest Center (New Jersey, USA) to determine rate of increase, lag time, maximum frequency, and the year of peak frequency. Overall, native and exotic species exhibited very similar population dynamics. Rates of increase and length of lag times were similar between native and exotic taxa but …

Native And Exotic Plant Species Exhibit Similar Population Dynamics During Succession, Scott J. Meiners

Faculty Research & Creative Activity

A growing body of literature has led to the debate in invasion biology whether exotic species perform within communities differently than native taxa due to inherent advantages. To address this issue, the population dynamics of native and exotic plant species were assessed from a 48-year record of permanent plot data from the Hutcheson Memorial Forest Center (New Jersey, USA) to determine rate of increase, lag time, maximum frequency, and the year of peak frequency. Overall, native and exotic species exhibited very similar population dynamics. Rates of increase and length of lag times were similar between native and exotic taxa but …

Performance Of Dionaea Muscipula As Influenced By Developing Vegetation, James O. Luken

Biology

Demography, growth, and flowering of Dionaea muscipula (Venus' fly trap) were studied during three years (2003–2005) following prescribed fire. Data were collected in permanent quadrats where the developing vegetation was either repeatedly clipped or allowed to grow. Clipping increased light availability at the soil surface. Over the study period, seedling establishment and flowering declined with increasing time since the last prescribed burn. Seedling densities did not differ between clipped and control quadrats, although greater numbers of seedlings grew to adult size in control quadrats and this significantly influenced population size-class structure. Clipping had no effect on leaf number or senescence, …

Ultrastructure Of Teliospores And Promycelium And Basidiospore Formation In The Four-Spored Form Of Gymnoconia Nitens, One Of The Causes Of Orange Rust Of Rubus, C. W. Mims, E. A. Richardson, Josephine Taylor

Faculty Publications

Orange rust of Rubus is an interesting disease because of the fact that it can be caused by three different rust fungi that produce virtually identical symptoms. One is Gymnoconia peckiana (Howe in Peck) Trotter, which is a demicyclic species, while the other two are endocyclic forms historically referred to as Gymnoconia nitens (Schwein.) Kern & H.W. Thurston. Although the spores produced on infected Rubus leaves by these latter two forms are morphologically identical to the aeciospores of G. peckiana, they actually function as teliospores. However, the teliospores of one of the forms gives rise to two-celled promycelia that …

Assessment Of Genetic Diversity In The Usda And Cip-Fao International Nursery Collections Of Quinoa (Chenopodium Quinoa Willd.) Using Microsatellite Markers [Abstract], S. A. Christensen, Donald B. Pratt, C. Pratt, P. T. Nelson, M. R. Stevens, Eric N. Jellen, C. E. Coleman, D. J. Fairbanks, A. Bonifacio, Peter J. Maughan

Faculty Publications

No abstract provided.

Additions To The Flora Of Connecticut, Gordon C. Tucker

Faculty Research & Creative Activity

Since the publication of the Connecticut checklist by Dowhan (1979), new state records have continued to appear. These were summarized by Mehrhoff (1995), including some made by Tucker ( 1987, 1991 ). Although geographically distant, the flora of Connecticut has continued to hold my attention since the publication of a flora of the southeastern part of the state (Tucker 1995). Over the past decade, I have made several collections that are new records for the state flora. These new records are reported in this paper, as well as a 1970 collection of Coronilla scorpio ides that was never added to …

Completed Chloroplast Genome Sequence Of Welwitschia Mirabilis: Analyses Of Gene Order And Content, Skip Mccoy

Undergraduate Honors Theses

While the use of complete chloroplast genome sequences in plant classification and phylogenetic studies has increased dramatically since the publication of the first genome in 1986, the position of the Gnetales within seed plants had been problematic due to lack of data. Here I report on the first Gnetalean to have its chloroplast genome sequenced, Welwitschia mirabilis. the genome is 119,726 base pairs in length, displaying large and small single copy regions (LSC and SSC), two copies of an inverted repeat region (IR), and contains only 99 unique gene species. The genome is the most compact genome sequenced to date, …

The Plant Structure Ontology, A Unified Vocabulary Of Anatomy And Morphology Of A Flowering Plant, Katica Ilic, Elizabeth Kellogg, Pankaj Jaiswal, Felipe Zapata, Peter Stevens, Leszek Vincent, Shulamit Avraham, Leonore Reiser, Anuradha Pujar, Martin Sachs, Noah Whitman, Susan Mccouch, Mary Schaeffer, Doreen Ware, Lincoln Stein, Seung Rhee

Biology Department Faculty Works

Formal description of plant phenotypes and standardized annotation of gene expression and protein localization data require uniform terminology that accurately describes plant anatomy and morphology. This facilitates cross species comparative studies and quantitative comparison of phenotypes and expression patterns. A major drawback is variable terminology that is used to describe plant anatomy and morphology in publications and genomic databases for different species. The same terms are sometimes applied to different plant structures in different taxonomic groups. Conversely, similar structures are named by their species-specific terms. To address this problem, we created the Plant Structure Ontology (PSO), the first generic ontological …

Spring Ephemeral Plant Diversity As It Relates To Gap Dynamics In Vigo County, Indiana, Jodi K. Farrell Sparks

All-Inclusive List of Electronic Theses and Dissertations

During the course of 25 years, plant specimens from several local locations have been collected and deposited into the Indiana State University (ISU) Herbarium by plant taxonomy students. The locations of some of these plots were reestablished in the spring of 2004. In each plot, all woody and spring herbaceous plants were collected from 26 February 2004 to 12 May 2004. These specimens were identified and compared to previous collections to examine species change in the context of gap dynamics. I compiled a species list for each plot and each preserve. Objectives for this thesis were to document plant diversity …

Influence Of Resource Pulses And Perennial Neighbors On The Establishment Of An Invasive Annual Grass In The Mojave Desert, Rebecca E. Drenovsky, J. J. James, M. A. Caird, R. L. Sheley

Biology

Invasion by exotic annual grasses is one of the most significant threats to arid ecosystems in the western USA. Current theories of invasibility predict plant communities become more susceptible to invasion whenever there is an increase in the amount of unused resources. The objective of this field study was to examine how resource pulses and temporal variation in resource demand by the native shrub vegetation influences establishment of the invasive annual grass Schismus arabicus. Water and nitrogen were applied as pulses in early spring, mid-spring, or continuously throughout the growing season to plots containing either Atriplex confertifolia or Atriplex …

Notes On Invasive Plants In The Rio Grande Delta Of Cameron County, Texas., Robert I. Lonard, Frank W. Judd

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

No abstract provided.

Genetics And Inheritance Of Seed Dormancy Inflicted By Seed- Coat Factors In Rice (Oryza Sativa L.), Z. L. Kanyeka

Tanzania Journal of Science

The study was undertaken to investigate the genetic mode of inheritance of dormancy imposed by the hull (seed coat) in rice seeds. Freshly harvested seeds of parents, F1 and F2 populations of a cross between a dormant cultivar Kisegese and non-dormant strain K2004 were used. Germination test of the de-hulled (without seed coat) and un-dehulled (whole or with seed coat) seeds were conducted at 10 days intervals starting at 15 days after harvesting (15DAH) for 65 days. The seeds were sown in petri dishes. Numbers of germinated and un-germinated seeds were recorded at 7 days after sowing. Germination of seeds …

Pathogenecity Of Two Strains Of Rice Yellow Mottle Virus On Aromatic Rice Cultivars, Z. L. Kanyeka

Tanzania Journal of Science

Development of rice cultivars with resistance to rice yellow mottle virus (RYMV) requires characterization of pathogenecity of existing strains against susceptible cultivars. The pathogenecity of two RYMV strains; S4 and S“New” identified in Tanzania were assessed against seven local and introduced rice genotypes including cultivars Zambia, ITA173 and TXD 88. The two virus strains showed similar effects on the rice cultivar Zambia killing all the plants at 25d after inoculation. The strains significantly reduced the plant height, panicle length, and number of tillers per pot and total dry matter of all the two cultivars. In another trial, the pathogenecity of …

A Subset Of Arabidopsis Ap2 Transcription Factors Mediates Cytokinin Responses In Concert With A Two-Component Pathway, Aaron M. Rashotte, Michael G. Mason, Claire E. Hutchison, Fernando J. Ferreira, G. Eric Schaller, Joseph J. Kieber

Dartmouth Scholarship

The plant hormone cytokinin regulates numerous growth and developmental processes. A signal transduction pathway for cytokinin has been elucidated that is similar to bacterial two-component phosphorelays. In Arabidopsis, this pathway is comprised of receptors that are similar to sensor histidine kinases, histidine-containing phosphotransfer proteins, and response regulators (ARRs). There are two classes of response regulators, the type-A ARRs, which act as negative regulators of cytokinin responses, and the type-B ARRs, which are transcription factors that play a positive role in mediating cytokinin-regulated gene expression. Here we show that several closely related members of the Arabidopsis AP2 gene family of …

Soil Microbial Community Composition As Affected By Restoration Practices In California Grassland, Rebecca E. Drenovsky, Martin Pothoff, Kerri L. Steenwerth, Louise E. Jackson, Rainer G. Joergensen, Kate M. Scow

Biology

Agricultural practices have strong impacts on soil microbes including both the indices related to biomass and activity as well as those related to community composition. In a grassland restoration project in California, where native perennial bunchgrasses were introduced into non-native annual grassland after a period of intensive tillage, weeding, and herbicide use to reduce the annual seed bank, microbial community composition was investigated. Three treatments were compared: annual grassland, bare soil fallow, and restored perennial grassland. Soil profiles down to 80cm in depth were investigated in four separate layers (0–15, 15–30, 30–60, and 60–80cm) using both phospholipid ester-linked fatty acid …