Biology Commons^™

Does Seed Size Affect The Rate Of Germination And Early Seedling Growth In Hairy Vetch?, Joy Ekpo

McCabe Thesis Collection

Size is an important characteristic of seed quality because larger seeds with larger volume contain more resources and are likely to exhibit greater vigor than smaller seeds (Ellis, 1992). In a range of plant species, seed size has been shown to affect germination rate, emergence rate, success of establishment, and growth (Black 1957; Bentley et al. 1980; Sanderson et al. 2002). Hairy vetch is an annual legume that is used for improvement of soil for pasture and to provide ground cover protecting against erosion (Duke 1981; Undersander 2002; Sattell et al 1988). Problems facing the establishment of hairy vetch are …

Moisture Potential Affects Rate Of Leaf Appearance In Cool Season Grasses, Nina Cherone Terrell

McCabe Thesis Collection

The rate of leaf appearance and onset of growth in cool season grasses may be influenced by soil moisture potential and exposure to below freezing temperatures. Levels of moisture potential and days exposed to freezing temperatures, which will restrict leaf appearance, are not well defined. The first part of this study was to determine the effects of different moisture potentials on the leaf appearance rates in two cool season grasses. Italian ryegrass (IRG) and tall wheat grass (TWG) were grown hydroponically at 4 moisture potentials in seed pouches in an incubator under a photoperiod of 13 hours light and 11 …

An Evaluation Of Submersed Aquatic Vegetation Transplanting Methods For Lake Pontchartrain Restoration, Donald Anthony Rodrigue Jr.

LSU New Orleans Theses and Dissertations

The general goals of this study were to evaluate transplant methods for Lake Pontchartrain submersed aquatic vegetation (SAV) restoration, and to compare survival and expansion of transplanted SAV among four sites. Two experiments were conducted from summer 2000 through spring 2001 at two north shore and two south shore sites in Lake Pontchartrain. Experiment 1 involved testing the effects of transplanting with matting, staples, exclosures, and interspecific interaction on survival and expansion of Ruppia maritima and Vallisneria americana transplants in Lake Pontchartrain. Experiment 2 involved testing the effects of transplanting with matting, staples, and plugs on Ruppia survival and expansion. …

Growth Rates, Survivorship, And Sex Ratios Of Juniperus Virginiana On The New Jersey Piedmont From 1963 To 2000, James A. Quinn, Scott J. Meiners

Faculty Research & Creative Activity

Growth rates, survivorship, and sex ratios of Juniperus virginiana on the New Jersey Piedmont from 1963 to 2000. J. Torrey Bot. Soc. XXX:000–000. 20XX.—Studies of the growth, survival, and sex ratios of dioecious species have been predominantly short-term. This research investigated growth rates, survivorship, and sex ratios among cohorts of Juniperus virginiana L. from 1963 through 2000. Males (M) and females (F) in six old-fields of different ages on the New Jersey Piedmont were analyzed, starting with the initial data on height and sex expression collected by John Small on labeled recruits from 1963 through 1976. These plants were relocated …

Growth Rates, Survivorship, And Sex Ratios Of Juniperus Virginiana On The New Jersey Piedmont From 1963 To 2000, James Quinn, Scott Meiners

Faculty Research & Creative Activity

Growth rates, survivorship, and sex ratios of Juniperus virginiana on the New Jersey Piedmont from 1963 to 2000. J. Torrey Bot. Soc. XXX:000–000. 20XX.—Studies of the growth, survival, and sex ratios of dioecious species have been predominantly short-term. This research investigated growth rates, survivorship, and sex ratios among cohorts of Juniperus virginiana L. from 1963 through 2000. Males (M) and females (F) in six old-fields of different ages on the New Jersey Piedmont were analyzed, starting with the initial data on height and sex expression collected by John Small on labeled recruits from 1963 through 1976. These plants were relocated …

Seed Mass And Morphology In Outcrossing And Selfing Species Of Clarkia (Onagraceae): An Sem Study, Jennifer L. Knies, Veronique A. Delesalle, A. R. Cavaliere

Biology Faculty Publications

Seeds from three pairs of outcrossing-selfing sister taxa from the genus Clarkia (farewell-to-spring, Onagraceae)—Clarkia unguiculata, Clarkia exilis, Clarkia xantiana ssp. xantiana and ssp. parviflora, and Clarkia concinna ssp. concinna and ssp. automixa—were studied to assess the effects of contrasting mating systems on seed mass and seed morphology. For each outcrossing-selfing comparison, the seed mass of the selfing taxon was less than that of the outcrossing taxon. Seed mass typically differed significantly among populations within a taxon. Scanning electron microscopy showed that the seeds from all these taxa share several characteristics: a bullet to shield shape, a reticulate exotesta pattern, presence …

Population Genetic Structure In Nolina Brittoniana (Agavaceae), A Plant Endemic To The Central Ridges Of Florida, Rebecca W. Dolan, Rebecca Yahr, Eric S. Menges

Scholarship and Professional Work - LAS

Nolina brittoniana is endemic to the central ridges of peninsular Florida. Its scrub and sandhill habitats have suffered extensive anthropogenic modification. Analysis of isozymes from populations throughout its range revealed less genetic variation than generally reported for endemic plants. Populations were well differentiated, with significant clines in allele frequency along the north-south axis of distribution. Pair-wise F-statistics calculated at four levels of population geographic substructure revealed that current and inferred historical habitat patches had similar genetic structure. We found no evidence of recent bottlenecks or changes in genetic structure due to habitat loss and fragmentation, consistent with populations having always …

Chemical Defenses In Garlic Mustard (Alliaria Petiolata) And Their Potential Role In Species Interactions In Forest Understories, Don Cipollini

Biological Sciences Faculty Publications

Garlic mustard [Alliaria petiolata [(M. Bieb) Cavara & Grande; Brassicaceae] is a European native biennial herb, first recorded on Long Island, NY in the 1860s, and is expanding rapidly in northeastern and midwestern forests in the U.S. and in southern Canada. Garlic mustard flourishes in moist woodlands with moderate exposure to light, but it can grow in a diversity of other habitats. It is found in natural areas, woodlots, and along edges of agricultural fields and lawns throughout North America. Several life history traits likely contribute to the invasiveness of this species. It has a high inbreeding rate and can …

A Guide To Growing Healthy Trees In The Lower Rio Grande Valley, Valley Proud Environmental Council, Texas Forest Service, Texas Urban Forestry Council, Brownsville Public Utilities Board, Brownsville Beautification Committee, Joe Ideker, Steve Benn, Beau Hollingsworth, Chris Best, Robert I. Lonard

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

No abstract provided.

Insect Infestation Of Maize, Zea Mays (L.) In Indigenous Storage Structures In Morogoro Region, Tanzania, Cp Rugumamu

Tanzania Journal of Science

Insect infestations and losses of maize stored in four types of indigenous storage structures in Morogoro Region, Tanzania were investigated. Infestation levels and weight losses caused by the larger grain borer, Prostephanus truncatus (Horn) and the maize weevil, Sitophilus zeamais (Motsch.) were found to differ significantly in the four types of storage structures (Dari, Kihenge, Kichanja and Reli). Lower infestation levels by the two pests and less weight losses were observed inDari and Kihenge than in Kichanja and Reli. The infestations and weight losses exhibited a significant trend that was in the order, Dari< Kihenge < Kichanja < Reli. These findings suggest that Dari and Kihenge are more appropriate for the incorporation in Integrated Pest Management (IPM) for P. truncatus and S. zeamais in Morogoro Region.

Nectar Rewards Of Insect-Adapted Flowers In A Forest/Farm Landscape: Measurement Challenges And Ecological Questions, Theresa Bordenkecher Dailey

All-Inclusive List of Electronic Theses and Dissertations

Native forest wildflowers of the Midwestern United States forests now compete with agricultural weeds for the attention of insect pollinators. The tiny quantities of nectar secreted by these insect-pollinated flowers are measured using laboratory techniques such as colorimetry. However, these techniques are used with the tacit assumption that nectar sugar identity does not affect estimates of carbohydrate content. I tested this hypothesis using fructose, glucose, and sucrose and found that after reaction with anthrone, fructose products differed from those of other sugars in light absorbance measured by a spectrophotometer. Potential error from using an inappropriate sugar standard is greater than …

Phenology Of Acacia Berlandieri, A. Minuata, A. Rigidula, A. Schaffneri, And Chloroleuconebano In The Lower Rio Grande Valley Of Texas During A Drought, Melissa R. Eddy, Frank W. Judd

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

Flowering and fruiting phenology of Acacia berlandieri, A. minuata, A. rigidula, A. schaffneri, and Chloroleucon ebano were studied at 3 sites in the Lower Rio Grande Valley of Texas from July 1998 through August 1999. Severe drought conditions prevailed for the 6 months preceding this study, and rainfall was 20% lower during the study than the long-term mean. Acacia berlandieri had the longest flowering period (5 months); each of the other 3 Acacia species flowered for 3 months. All of the Acacia species flowered in winter or spring (at relatively low temperatures and increasing photoperiod). Peak flowering occurred in February …

Comparison Of Native Brushland, Replanted, And Unaided Secondary Succession Plant Communities In The Lower Rio Grande Valley Of Texas, Mitchell Allen Sternberg

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

Agriculture and urban development have destroyed 95% of native brushland habitat in the Lower Rio Grande Valley (LRGV) of south Texas. Therefore, habitat restoration is an important issue in the LRGV. Since 1982, the U.S. Fish and Wildlife Service has been replanting areas in the LRGV to native brushland species to establish a wildlife corridor along the lower reach of the Rio Grande. Vegetation composition of a mature brushland, a replanted habitat and an unaided secondary succession site (fallow field) were examined at one locale in the LRGV in 1999. The mature brushland edge plot had the highest species richness …

The B-Subunit Of The Arabidopsis G Protein Negatively Regulates Auxin-Induced Cell Division And Affects Multiple Developmental Processes, Hemayet Ullah

Department of Biology Faculty Publications

Plant cells respond to low concentrations of auxin by cell expansion, and at a slightly higher concentration, these cells divide. Previous work revealed that null mutants of the alpha-subunit of a putative heterotrimeric G protein (GPA1) have reduced cell division. Here, we show that this prototypical G protein complex acts mechanistically by controlling auxin sensitivity toward cell division. Loss-of-function G protein mutants have altered auxin-mediated cell division throughout development, especially during the auxin-induced formation of lateral and adventitious root primordia. Ectopic expression of the wild-type Galpha-subunit phenocopies the Gbeta mutants (auxin hypersensitivity), probably by sequestering the Gbetagamma-subunits, whereas overexpression of …

The Vascular Flora Of The Tablelands: A Natural Region In The Northeastern Section Of The Knobs Of Kentucky, Kim L. Feeman

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Kim L. Feeman on January 22, 2003.

A Watershed Analysis Of Threemile Pond: Implications For Water Quality And Land Use Management, Colby Environmental Assessment Team, Colby College, Problems In Environmental Science Course (Biology 493), Colby College

Colby College Watershed Study: Threemile Pond (2003)

The 2003 Colby Environmental Assessment Team chose to study the Threemile Pond watershed. The Threemile Pond watershed is located in Vassalboro, China., Windsor, and Augusta, Maine. Threemile Pond is a popular site for recreation and is home to a wide range of flora and fauna. Like all other lakes in Maine, it is a young lake. However, intensive human activity in the watershed contributes a substantial amount of nutrients and the lake has algal blooms annually in the summer months. The purpose of this study was to assess the impact of land use and development on the water quality of …

Blackspot Disease Of Roses [Abstract], Robert J. Wiggers, Josephine Taylor, J. A. Margoitta, S. G. Pandalai

Faculty Publications

No abstract provided.

An Overview Of Aircraft Remote Sensing In Integrated Pest Management, James H. Everitt, Kenneth R. Summy, D. E. Escobar, M. R. Davis

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

English: This paper presents four exemplary applications of aerial photography and videography, global positioning system (GPS), and geographic information system (GIS) technologies for detecting, monitoring, and mapping insect infestations in agriculture, forestry, and rangeland areas. Applications demonstrated include detecting and mapping: (1) citrus blackfly (Aleurocanthus woglumi Ashby) infestations in citrus orchards; (2) silverleaf whitefly (Bemisia argentifolii Bellows and Perring) infestations in cotton; (3) harvester ant (Pogonomyrmex barbatus F. Smith) infestations on rangelands; and (4) western pine beetle (Dendroctonus brevicomis LeConte) infestations in a forested area. The integration of a GPS with the video imagery permitted latitude and longitude coordinates of …

Comparative Studies Of Evolutionary Responses To Light Environments In Arabidopsis, Massimo Pigliucci, Heidi Pollard, Mitchell B. Cruzan

Biology Faculty Publications and Presentations

In this article, we compare the reaction norms to foliage shade (changes in light quality, spatially fine-grained environmental variation) and photoperiod (day length, spatially coarse-grained environmental variation) in several haplotypes of Arabidopsis thaliana from Scandinavia. We found that both across-environment means and phenotypic plasticities evolved continuously and very rapidly within this group. Both character means and trait plasticities were highly integrated, in part as predicted by the adaptive plasticity hypothesis for response to foliage shade (the so-called shade-avoidance syndrome). We found that a significant but small fraction of the variance in across-treatment trait means and plasticities in response to one …

Detecting Stress In Glasshouse Plants Using Color Infrared Imagery: A Potential New Application For Remote Sensing, Kenneth R. Summy, Christopher R. Little, Ruben A. Mazariegos, James H. Everitt, M. R. Davis, J. V. French, A. W. Scott Jr.

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

English: Studies were conducted to evaluate the effectiveness of color infrared (CIR) film for detecting physiological stress in plants located within glasshouse structures. Spectroradiometer measurements obtained within and outside of a structure constructed of polycarbonate plastic indicated no significant attenuation or disruption of visible and near-infrared radiation entering the structure. CIR photographs of cucumber seedlings (Cucumis sativus) obtained within the greenhouse were comparable in quality to those obtained outside the structure, and clearly distinguished between foliage of healthy plants and those subjected to a moderate level of nitrogen stress. In CIR imagery of a trifoliate orange tree (Poncirus trifoliata (L.) …

Cissus Sicyoides C. Linnaeus (Vitaceae), A Potential Exotic Pest In The Lower Rio Grande Valley, Texas, J. V. French, Robert I. Lonard, James H. Everitt

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

English:Cissus sicyoides C. Linnaeus, a perennial vine native to tropical Mexico, Central America, and the Caribbean, has recently been rediscovered in the Lower Rio Grande Valley,Texas. A dense population of this exotic species has been located in a brushy area along a canal network and in two adjacent citrus groves near Weslaco. This species produces a dense mantle that covers other vegetation, appears to be invasive, and may pose a potential weed problem in citrus in the Lower Rio Grande Valley.

Spanish: Cissus sicyoides C. Linnaeus, una enredadera perene nativa de los trópicos de México, América Central y el Caribe, …

Relationships Between Blueberry Flower Age, Pollination, And Conidial Infection By Monilinia Vaccinii-Corymbosi, Jeffery S. Lehman, Henry K. Ngugi, Harald Scherm

Biology and Earth Science Faculty Scholarship

Monilinia vaccinii-corymbosi infects open blueberry flowers via the gynoecial pathway, leading to mummification of the developing fruit. To determine the effect of flower age on infection, stigmata were inoculated with conidia of M. vaccinii-corymbosi between 0 and 5 days after anthesis, fungal growth rates through the stylar canal were measured in detached flowers in the laboratory, and fruit disease incidence was determined in plants grown in the greenhouse. Hyphal growth rates were greatest in flowers inoculated on the day of anthesis, declined linearly with increasing flower age at inoculation (r = 0.921; P < 0.0001; n = 12), and were unaffected by the presence or absence of pollen applied at the time of inoculation. In greenhouse-grown plants, the percentage of infected fruit decreased exponentially with increasing flower age at inoculation (R = 0.878; P = 0.0057; n = 10), with disease incidence ranging from 76.4% for flowers inoculated on the day of anthesis to 15.5% for those inoculated 4 days later. Fruit disease incidence in the greenhouse was linearly correlated with hyphal growth rates in detached flowers (r = 0.985; P < 0.0001; n = 9), justifying the use of detached flowers when investigating gynoecial infection by M. vaccinii-corymbosi. In separate experiments, the effects of timing and sequence of pollination and inoculation on hyphal growth rates through the stylar canal and on disease incidence were investigated. Application of pollen to detached flowers 1 or 2 days before inoculation reduced hyphal growth rates by between 14.0 and 42.9% compared with flowers that received pollen and conidia simultaneously. Similarly, reductions in fruit disease incidence by between 9.5 and 18.3% were observed on greenhouse-grown plants for pollination-to-inoculation intervals ranging from 1 to 4 days. These results document that newly opened flowers are most susceptible to infection by M. vaccinii-corymbosi and that fruit disease incidence is reduced if pollination occurs at least 1 day before inoculation. Strategies that lead to early pollination of newly opened flowers may be useful for managing mummy berry disease in the field.

Riparian Vegetation Of The Lower Rio Grande, Robert I. Lonard, Frank W. Judd

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

The riparian vegetation of the lower reach of the Rio Grande was studied at 7 locations using 3 line intercepts at each location. There were no trees at the mouth of the river and the vegetation was similar to that found along the Laguna Madre shore of barrier islands. Mesquite (Prosopis glandulosa) was the dominant tree near the coast and in the western section of the river near Falcon Dam. Sugar hackberry (Celtis laevigata) was the dominant tree species at all other sites except at Santa Ana National Wildlife Refuge, where cedar elm (Ulmus crassifolia) and anacua (Ehretia anacua) were …

Role Of A Heterotrimeric G Protein In Regulation Of Arabidopsis Seed Germination, Hemayet Ullah, Jin-Gui Chen, Shucai Wang, Alan Jones

Department of Biology Faculty Publications

Seed germination is regulated by many signals. We investigated the possible involvement of a heterotrimeric G protein complex in this signal regulation. Seeds that carry a protein null mutation in the gene encoding the alpha subunit of the G protein in Arabidopsis (GPA1) are 100-fold less responsive to gibberellic acid (GA), have increased sensitivity to high levels of Glc, and have a near-wild-type germination response to abscisic acid and ethylene, indicating that GPA1 does not directly couple these signals in germination control. Seeds ectopically expressing GPA1 are at least a million-fold more responsive to GA, yet still require GA for …

Myriophyllum Spicatum Invasion In Cave Run Lake, Kentucky, Rob A. Tewes

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Rob A Tewes on May 1, 2002.

Survival Of And Herbivore Damage To A Cohort Of Quercus Rubra Planted Across A Forest-Old-Field Edge, Scott J. Meiners, Matthew J. Matinkovic

Faculty Research & Creative Activity

Forest edges are known to affect plant community composition and habitat use by animals. However, the direct influence of edges in determining patterns of tree regeneration is poorly understood. Survival of and herbivore damage to Quercus ruln-a seedlings were experimentally determined for seedlings planted across a forest--old-field edge gradient. Seedling survival was lowest inside the forest ( 1%), intermediate at the edge (25%) and highest within the old-field portion of the gradient (49%). Deer herbivory decreased with increasing distance into the old field. Seedling survival increased under Rosa multiflora and decreased in plots with mammalian herbivory. Seedling height was significantly …

Survival Of And Herbivore Damage To A Cohort Of Quercus Rubra Planted Across A Forest-Old-Field Edge, Scott Meiners, Matthew Matinkovic

Faculty Research & Creative Activity

Forest edges are known to affect plant community composition and habitat use by animals. However, the direct influence of edges in determining patterns of tree regeneration is poorly understood. Survival of and herbivore damage to Quercus ruln-a seedlings were experimentally determined for seedlings planted across a forest--old-field edge gradient. Seedling survival was lowest inside the forest ( 1%), intermediate at the edge (25%) and highest within the old-field portion of the gradient (49%). Deer herbivory decreased with increasing distance into the old field. Seedling survival increased under Rosa multiflora and decreased in plots with mammalian herbivory. Seedling height was significantly …

Probability Of Tree Seedling Establishment Changes Across A Forest–Old Field Edge Gradient, Scott J. Meiners, Steward T.A. Pickett, Steven N. Handel

Faculty Research & Creative Activity

Forest edges affect many aspects of plant communities, causing changes in microclimate, species composition, and community structure. However, the direct role of edges in regulating forest regeneration is relatively unknown. The pattern of tree establishment across a forest–old field edge was experimentally examined to determine the response of three tree species to the edge gradient. We placed 100 1-m2 plots in a 90 3 90 m grid that began 30 m inside the forest, extended across the edge, and ended at 60 m into the old field. Into each plot, we planted seeds of Acer rubrum, Acer saccharum, and Quercus …

Probability Of Tree Seedling Establishment Changes Across A Forest–Old Field Edge Gradient, Scott Meiners, Steward Pickett, Steven Handel

Faculty Research & Creative Activity

Forest edges affect many aspects of plant communities, causing changes in microclimate, species composition, and community structure. However, the direct role of edges in regulating forest regeneration is relatively unknown. The pattern of tree establishment across a forest–old field edge was experimentally examined to determine the response of three tree species to the edge gradient. We placed 100 1-m2 plots in a 90 3 90 m grid that began 30 m inside the forest, extended across the edge, and ended at 60 m into the old field. Into each plot, we planted seeds of Acer rubrum, Acer saccharum, and Quercus …

Production Of Cell Wall Enzymes In Pepper Seedlings, Inoculated With Arbuscular Mycorrhiza Glomus Etunicatum, A C Odebode, A O Salami, O Osunubi

Tanzania Journal of Science

Pepper seedlings inoculated with arbuscular mycorrhizal AM fungus, Glomus etunicatum, produced cellulase, polygal-acturonase and pectin methylestrase enzymes. The activities of the enzymes increased as the pepper seedlings matured in age, showing that the activity of the enzymes in the seedlings was age mediated. The pectinases showed higher activity than the cellulase enzyme which may indicate establishment of the mycorrhizal in the host. The significance of this finding is that there is an initial infectivity factor in (AM) fungi interactions with plant just like in other host-parasite interaction.