Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Plant Biology

1989

Institution
Keyword
Publication
Publication Type

Articles 1 - 29 of 29

Full-Text Articles in Life Sciences

Introduction And Enhancement Of Vegetative Cover At Lake Mead, Jennifer S. Haley, Lisa K. Croft, Suzanne E. Leavitt, Larry J. Paulson Dec 1989

Introduction And Enhancement Of Vegetative Cover At Lake Mead, Jennifer S. Haley, Lisa K. Croft, Suzanne E. Leavitt, Larry J. Paulson

Publications (WR)

Studies done by the Nevada Department of Wildlife (NDOW) and the Arizona Fish and Game between 1978 and 1981 indicate that inadequate cover may be limiting the production and survival of largemouth bass at the Lake Mead National Recreation Area (LMNRA). As a result of these studies, NDOW initiated a contract in 1986 with the Lake Mead Research Center (LMRC) to investigate means of improving habitat for game fish by introducing natural and/or artificial cover.

During Phase I (1986-1987) of this contract, the shoreline of Lake Mead was surveyed for aquatic and terrestrial plant growth. Also during this time ...


Presence Of A Cs-Resistant Transient Outward Current Which Distorts Ica Measurements In Guinea-Pig Single Ventricular Cells, Georges Christé, Brigitte Delachapelle, Fouad Lemtiri-Chlieh, Carlos Ojeda Nov 1989

Presence Of A Cs-Resistant Transient Outward Current Which Distorts Ica Measurements In Guinea-Pig Single Ventricular Cells, Georges Christé, Brigitte Delachapelle, Fouad Lemtiri-Chlieh, Carlos Ojeda

fouad Lemtiri-Chlieh

To correctlyr analyse the physical properties of ion channels and the actions of drugs upon them, it is important that the membrane conducts only the ionic species believed permeant. In guinea-pig ventricular cells it has been assumed that only ICaL flows in the potential range -50 to +60 mV in the presence of intra- and extracellular Cs (> 20 mM). We report here that this is not the case due to the presence of a Cs-insensitive, transient outward current.


Measurements Of Cytosolic Free Ca In Cultured Rat Neonate And Adult Guinea-Pig Ventricular Cardiac Myocytes, Jean-Claude Bernengo, Fouad Lemtiri-Chlieh, Carlos Ojeda, Nadine Pltonoff Nov 1989

Measurements Of Cytosolic Free Ca In Cultured Rat Neonate And Adult Guinea-Pig Ventricular Cardiac Myocytes, Jean-Claude Bernengo, Fouad Lemtiri-Chlieh, Carlos Ojeda, Nadine Pltonoff

fouad Lemtiri-Chlieh

Cytosolic free Ca was measured with Indo-1 (Grynkiewicz et al. 1985) as free acid (in guinea-pig cells) or as the ester (in rat neonate cells). Using image analysis we obtained concentration maps at 40 ms intervals at two wavelengths (Cannell et al. 1986). In rat neonate cells, at rest and during contraction, calcium was apparently non-uniformly distributed, in contrast to guinea-pig adult cells. Using a dual PM spectroscopic system adapted to an inverted microscope we found: (1) the conversion of Indo-AM to Indo- 1 in the cytosol is not complete (< 40% contribution to the total light); (2) rat neonate cells buffer Ca (at rest 130-170 nM) only for [Ca]. between 1 and 3 mM, whereas in adult guinea-pig cells the range extended to 10 mM; (3) during contraction [Ca]i rose from 200 nm to no more than 1 microM. Digitoxin increases basal and peak [Ca]i; (4) during spontaneous contractions, in guinea-pig cells, [Ca]i rises from 70 to 200 nm when [Ca]o = 0, and from 170 nm to about 1 microM when [Ca]o = 2 mM; (5) in voltage-clamp conditions the rise in [Ca]i does not exceed 2 microM and oscillations occur in the presence of forskolin. When loading with Indo-1, cells frequently cease to contract (Powell et al. 1988) and the variations in [Ca]i are then very small (about 200 nm at peak ICa). In both cases these values are small compared to the total charge crossing the membrane.


Noteworthy Collections: Virginia, W. John Hayden Sep 1989

Noteworthy Collections: Virginia, W. John Hayden

Biology Faculty Publications

The above collections represent the second record for the state of Virginia, and may well establish the northernmost station for the species in the eastern United States. According to B.L. Lipscomb (Sida 8:320-327. 1980), this Old World weed is spreading throughout the warmer regions of North America. The only previous record of the species from the state is a Fernald specimen from Owl Creek in Virginia Beach. R.W. Tyndall, who found the species in northeastern North Carolina, was unable in 1978 to locate the plant at Fernald's Virginia Beach locality (Castanea 48:277-280. 1983). The Amelia ...


Temporal Patterns Of Nectar And Pollen Production In Aralia Hispida: Implications For Reproductive Success, James D. Thomas, Mary A. Mckenna, Mitchell B. Cruzan Aug 1989

Temporal Patterns Of Nectar And Pollen Production In Aralia Hispida: Implications For Reproductive Success, James D. Thomas, Mary A. Mckenna, Mitchell B. Cruzan

Biology Faculty Publications and Presentations

Large plants of Aralia hispida present their pollen and nectar in hundreds of small flowers than open sequentially over 2—3 wk in a pattern of synchronized protandry that alternates male and female phases. The primary pollinators, bumble bees, are able to discover individual plants with elevated levels of either nectar or pollen, and to return to them more often than to less rewarding plants. Both pollen and nectar are presented gradually over time in such a way as to favor traplining behavior by the bees, with many, frequent visits. In controlled environments, lifetime sugar production per flower varies among ...


The Effects Of Varying Light Exposure Times On The Colonization And Sporulation Of Gigaspora Margarita In The California Pepper, Mary E. Kirker Jul 1989

The Effects Of Varying Light Exposure Times On The Colonization And Sporulation Of Gigaspora Margarita In The California Pepper, Mary E. Kirker

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Arts and Sciences at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by Mary E. Kirker on July 24, 1989.


Flora Of Richmond National Battlefield Park, Virginia, W. John Hayden, Melanie Lynn Haskins, Miles F. Johnson, James M. Gardner Jun 1989

Flora Of Richmond National Battlefield Park, Virginia, W. John Hayden, Melanie Lynn Haskins, Miles F. Johnson, James M. Gardner

Biology Faculty Publications

An inventory of the vascular flora of nine of eleven units of Richmond National Battlefield Park was compiled from 1985 to 1987. Each site was visited during the growing season in two to four week intervals; plant species were identified and recorded in the field and/or collected for later study. A total of 761 different species were identified in the surveyed units, and 2487 individual records of species per particular park unit were noted. Twenty-three percent of the flora consists of exotic species, largely from Eurasia. Voucher specimens are housed in the herbaria of the University of Richmond and ...


Characterization Of The Alternative Respiratory Pathway In Soybean , David Michael Obenland Jan 1989

Characterization Of The Alternative Respiratory Pathway In Soybean , David Michael Obenland

Retrospective Theses and Dissertations

The alternative respiratory pathway may be important in the energy economy of higher plants. The objective of this study was to characterize the alternative pathway in soybean and to gain a better understanding of the importance of this respiratory pathway to soybean productivity;Capacity for the alternative pathway was assessed in leaf and root tissue of male-sterile and fertile soybean plants and in leaf, embryonic axis and epicotyl tissue, as well as isolated mitochondria, of pea (Pisum sativum L.) by measurement of oxygen uptake in the presence and absence of KCN and salicylhydroxamic acid (SHAM). Male-sterile and fertile soybean tissues ...


Enzymology Of L-Proline Synthesis , Prashant John Rayapati Jan 1989

Enzymology Of L-Proline Synthesis , Prashant John Rayapati

Retrospective Theses and Dissertations

The accumulation of free L-proline in leaves as a response to water deficit is well documented. Accumulation is caused by stress enhanced-de novo proline synthesis from glutamic acid. Three enzymes, gamma-glutamyl kinase (GK, EC 2.7.2.11), gamma-glutamyl phosphate reductase (GPR, EC 1.2.1.41), and pyrroline-5-carboxylate reductase (PCR, EC 1.5.1.2) catalyze the pathway in other organisms;A continuous assay for GK was developed. A crude preparation from etiolated shoots of Vigna radiata L. was capable of synthesizing pyrroline-5-carboxylate (P5C) from glutamic acid. Attempts to purify GPR activity yielded P5C dehydrogenase activity that was not ...


Effects Of Low-Oxygen Atmospheres On Impatiens Seed Germination , Paul Thomas Karlovich Jan 1989

Effects Of Low-Oxygen Atmospheres On Impatiens Seed Germination , Paul Thomas Karlovich

Retrospective Theses and Dissertations

The effects of low-oxygen atmospheres on the germination of Impatiens wallerana Hook. f. were tested and related to germination in the plug-production system. The cultivars tested could germinate partially under water, but the germination rate was slower and the germination meantime was longer for all cultivars but one. There was little variability among cultivars germinated on blotter paper, but much greater variability was found when the seeds were germinated under water. Although impatiens seeds could germinate when submerged, they were not able to germinate in seven days at 0% oxygen, and essentially no germination occurred in 3% oxygen. At oxygen ...


Increased Returns From Agronomic Inputs In Early Sown Cereal Crops, W K. Anderson Jan 1989

Increased Returns From Agronomic Inputs In Early Sown Cereal Crops, W K. Anderson

Journal of the Department of Agriculture, Western Australia, Series 4

When crop variety and soeing dae are matched so that flowering occurs in the 'window' for a particular site, grain yields are increased and yield response to inputs such as nitrogen fertilizer and seeding rate is magnified.

This response occurs because the srop's potential for setting and filling grains is much improved by sowing at the optimum time. However varieties differ in their yield potential because they have different lenghts of growing season, which probably affects grain numbers, and because they have different inherent grain sizes. These differences affect the way varieties react to sowing date. Figure 1 shows ...


Tallgrass Prairie Remnants Of Eastern Nebraska, Judith F. Boettcher, Thomas B. Bragg Jan 1989

Tallgrass Prairie Remnants Of Eastern Nebraska, Judith F. Boettcher, Thomas B. Bragg

Biology Faculty Proceedings & Presentations

Ten eastern Nebraska tallgrass prairie remnants were evaluated up to four times during the 1979 growing season to assess vegetative composition and the effects of mowing, topographic and size differences, and season of evaluation. Frequent mowing resulted in a reduced canopy cover of some species, such as big bluestem (Andropogon gerardii Vitman) (21% lower with frequent mowing), but increased cover of others, particularly the introduced species smooth brome (Bromus inermis Leyss. subsp. inermis) (35% higher cover with frequent mowing). In addition, frequent mowing resulted in a higher proportion of disturbance species. Comparing the time of mowing, canopy cover of warm-season ...


Effect Of Eastern Red Cedar On Seedling Establishment Of Prairie Plants, Dan J. Stipe, Thomas B. Bragg Jan 1989

Effect Of Eastern Red Cedar On Seedling Establishment Of Prairie Plants, Dan J. Stipe, Thomas B. Bragg

Biology Faculty Proceedings & Presentations

To test the hypothesis that eastern red cedar (Juniperus virginiana L.) is allelopathic, seedling establishment of five herbaceous prairie species was evaluated by growing seeds in soil collected beneath and adjacent to a stand of this tree species. While four species showed no significant effect, the germination of one species, finger coreopsis (Coreopsis palmata Nutt.), was significantly reduced. Since eastern red cedar is an early invader of unburned prairie, such an allelopathic effect, even on only a few species, is of particular concern in that it has the potential to hasten degradation of invaded prairie sites.


Establishing Warm-Season Grasses And Forbs Using Herbicides And Mowing, Thomas B. Bragg, David M. Sutherland Jan 1989

Establishing Warm-Season Grasses And Forbs Using Herbicides And Mowing, Thomas B. Bragg, David M. Sutherland

Biology Faculty Proceedings & Presentations

The objective of this study was to provide a preliminary assessment of the use of selected herbicides in establishing a diverse stand of prairie grasses and forbs. An upland and a lowland site in eastern Nebraska, consisting of well-drained, fine-silty clay, loess-derived soils, were seeded with 23 native prairie grass and forb species and subsequently mowed or treated at rates of 0.6, 1.1, 1.7, and 2.2 kg/ha with atrazine [6-chloro-Nethyl- N' -(l-methylethyl)-l ,3,S-triazine-2,4-diamine] or 2,4-0 (2,4-dichlorophenoxyacetic acid). Treatments were applied at one and two-year intervals. Canopy cover in unreplicated treatment ...


Effect Of Burning On Germination Of Tallgrass Prairie Plant Species, Sherry R. Rohn, Thomas B. Bragg Jan 1989

Effect Of Burning On Germination Of Tallgrass Prairie Plant Species, Sherry R. Rohn, Thomas B. Bragg

Biology Faculty Proceedings & Presentations

Seeds from 10 prairie plant species of burned and unburned portions of three tallgrass prairies were collected and tested for germinability. Germination of big bluestem (Andropogon gerardii Vitman) consistently averaged higher with burning. Indiangrass (Sorghastrum nutans L.) and sideoats grama [Bouteloua curtipendula (Michx.) Torr.] averaged 5% higher with burning on two of the three sites, although for indiangrass average germination for all three sites was 7% lower. Species for which germination declined with burning were false sunflower [Heliopsis helianthoides (L.) Sweet var. scabra (Dun.) Fern.], -13%; whole leaf rosinweed (Silphium integrifolium Michx.), -10%; and white prairieclover (Dalea candida Michx. ex ...


Characterization Of The Joint Effects Of Tridiphane And Paraquat In Soybean , Christopher Paul Dionigi Jan 1989

Characterization Of The Joint Effects Of Tridiphane And Paraquat In Soybean , Christopher Paul Dionigi

Retrospective Theses and Dissertations

Visual ratings of percent injury indicated that exposure to tridiphane may increase herbicide-induced oxidative stress in field-grown plants. The objectives of these studies were to characterize the combined effects of tridiphane and paraquat-induced oxidative stress and to determine the physiological factors that underlie these combined effects. Field studies indicate that, under certain conditions, exposure to tridiphane can increase paraquat-induced leaf injury and inhibition of soybean plant height accumulation compared to the injury produced by paraquat applied alone. However, chlorophyll bleaching studies conducted in the field, and electrolyte leakage studies conducted under controlled environmental conditions indicate that exposure to tridiphane does ...


Examination And Development Of An Essential Oil Industry In The Ord River Irrigation Area Of North Western Australia, Jean M.V. Bonnardeaux Jan 1989

Examination And Development Of An Essential Oil Industry In The Ord River Irrigation Area Of North Western Australia, Jean M.V. Bonnardeaux

Research Reports

The project aimed at establishing an essential oil industry in the Ord River Irrigation Area (ORIA). This industry is particularly suited to the ORIA where transport costs often prohibit the development of some agricultural products. The oils are concentrated and highly valuable. In addition, the ORIA with its abundant water and high temperatures presents a unique opportunity to grow a wide range of crops for the production of essential oils used by the food, medicinal and perfume industries. Australia has therefore an opportunity to initiate a new industry capable of replacing imports and gaining access to world markets representing a ...


Water Relations Of Obligate Riparian Plants As A Function Of Streamflow Diversion On The Bishop Creek Watershed, S. D. Smith, J. L. Nachlinger, A. B. Wellington, C. A. Fox Jan 1989

Water Relations Of Obligate Riparian Plants As A Function Of Streamflow Diversion On The Bishop Creek Watershed, S. D. Smith, J. L. Nachlinger, A. B. Wellington, C. A. Fox

Life Sciences Faculty Publications

We investigated the water relations of obli-gate riparian plants on paired diverted and undiverted reaches on Bishop Creek, Eastern Sierra Nevada. Ri-parian plants on diverted reaches had reduced stomatal conductance and water potential compared to plants on undiverted reaches in a dry year, but not in a high runoff year. Juvenile plants on diverted reaches had reduced stomatal conductance and lower midday water potentials relative to surrounding mature trees, a trend that was not observed on undiverted reaches. Plants on diverted reaches possessed significantly smaller, thicker leaves and a reduced total leaf area relative to trees on streamside reaches. Reduced ...


Riparian Plant Water Relations Along The North Fork Of The Kings River, California, J. L. Nachlinger, S. D. Smith, R. J. Risser Jan 1989

Riparian Plant Water Relations Along The North Fork Of The Kings River, California, J. L. Nachlinger, S. D. Smith, R. J. Risser

Life Sciences Faculty Publications

Plant water relations of five obligate ripar-ian species were studied along California's North Fork Kings River. Diurnal stomatal conductance, transpi-ration, and xylem pressure potentials were measured throughout the 1986 growing season and in mid-season in 1987. Patterns were similar for all species although absolute values varied considerably. Maximum stomatal conductance occurred early in the day and season during favorable environmental conditions and decreased as air temperature and the vapor pressure difference between the leaf and air increased. Maximum transpiration rates occurred in mid-morning and mid-summer resulting in estimated daily water losses per unit sunlit leaf area of 163-328 mol ...


An Isotopic Analysis Of The Hydrology And Riparian Vegetation Water Sources On Bishop Creek, M. L. Space, J. W. Hess, S. D. Smith Jan 1989

An Isotopic Analysis Of The Hydrology And Riparian Vegetation Water Sources On Bishop Creek, M. L. Space, J. W. Hess, S. D. Smith

Life Sciences Faculty Publications

Five power generation plants along an eleven kilometer stretch divert Bishop Creek water for hydro-electric power. Stream diversion may be adversely affecting the riparian vegetation. Stable isotopic analysis is employed to determine surface water/ground-water interactions along the creek. surface water originates primarily from three headwater lakes. Discharge into Bishop Creek below the headwaters is primarily derived from ground water. The average δD and δ18O values are significantly different for surface water and ground water that an isotopic analysis can delineate between these two components of flow. Therefore isotopic shifts along the creek can determine gaining reaches. In addition, by ...


Woody-Plant Succession In An Eastern Nebraska Bluff Forest, Douglas E. Borland, Thomas B. Bragg, David M. Sutherland Jan 1989

Woody-Plant Succession In An Eastern Nebraska Bluff Forest, Douglas E. Borland, Thomas B. Bragg, David M. Sutherland

Biology Faculty Publications

Woody plant composition of ridgetop old-fields abandoned at various times since 1800 suggest a successional pattern for an eastern Nebraska bluff forest. Sites abandoned for 24 years were dominated by elm (Ulmus spp.) and rough-leaved dogwood (Comus drummondii). Other sites, abandoned for76 years, were dominated by bitternut hickory (Cwya cordijormis), American linden (Tilia americana), and hop-hombeam (Ostrya virginiana), and those abandoned for 186 years were predominantly bur oak (Quercus macrocarpa) and hop-hornbeam. Based on species importance values, we conclude that the composition of this forest is still changing.


An Annotated List Of The Vascular Plants Of Keith County, Nebraska, David M. Sutherland, Steven B. Rolfsmeier Jan 1989

An Annotated List Of The Vascular Plants Of Keith County, Nebraska, David M. Sutherland, Steven B. Rolfsmeier

Biology Faculty Publications

This study provides an annotated list of the vascular plants known to exist outside of cultivation in Keith County, Nebraska. Listed are a total of 599 species, subspecies and varieties belonging to 302 genera of 87 families. Notes are included about frequency and habitat for each of the taxa. 264 (44.1 %) of the taxa listed were previously unreported for Keith County. Additionally, the paper discusses vegetation regions in the county and gives information in tabular form about numbers of the flora in different taxa, the ten largest families, numbers of taxa of different growth habits, and numbers of taxa ...


Early Sowing : One Key To Improved Yields Of Cereal Crops, M W. Perry, Wal Anderson, Rob Delane Jan 1989

Early Sowing : One Key To Improved Yields Of Cereal Crops, M W. Perry, Wal Anderson, Rob Delane

Journal of the Department of Agriculture, Western Australia, Series 4

Early sowing of cereal crops is one of the most important management practices through which Western Australian cereal growers can increase yields.

Researchers have long known that in theory early sowing should mean improved growth and water use efficiency - which both contribuite to increased yields. Application of this knowledge has had to await new tillage and herbicide technology, but recent research in the northan and central wheatbelt has now demonstrated the advantages of early sowing in practice. And more exciting yet, there is evidence that yield responses to weed control and applied fertilizers may also be greater in early sown ...


Frost Injury To Wheat, S P. Loss Jan 1989

Frost Injury To Wheat, S P. Loss

Journal of the Department of Agriculture, Western Australia, Series 4

Frost injury has not been a major concern to the Western Australian wheat industry despite causing spectacular but irregular crop losses on some farms.

The development of suitable herbicides, direct drilling technology and the adoption of early flowering varieties in the late 1970s and early 1980s led to wheat crops being sown and flowering earlier than previously. This resulted in an increase in the incidence of frost damage.

Research into frost indicates that most wheat producers face low to moderate risks of yield loss caused by frost. However, individual farms in particular years can suffer devestating widespread losses. Grost injury ...


Flower : Predicting Flowering Times Of Cereal Crops, G A B Elliott, Stephen Loss Jan 1989

Flower : Predicting Flowering Times Of Cereal Crops, G A B Elliott, Stephen Loss

Journal of the Department of Agriculture, Western Australia, Series 4

FLOWER is a computer program which predicts the flowering date of a given wheat or barley variety at a specified location and sowing date. Department of Agriculture agronomists, breeders and advisers are using the program to provide useful information on how the development of cereals responds to different environments across Western Australia's cereal growing areas.


Early Sowing Of Ceral Crops In Low Rainfall Areas, R J. Delane, John Hamblin Jan 1989

Early Sowing Of Ceral Crops In Low Rainfall Areas, R J. Delane, John Hamblin

Journal of the Department of Agriculture, Western Australia, Series 4

One of the objectives of the Department of Agriculture's crop research in the low rainfall, northern wheatbelt is to develop crop varieties and management practices that will make best use of stored water on both sandplain and fine textured soils. Sowing a crop early will improve its water use efficiency and yiel in low rainfall areas.


Concetta Tm (Papconc) C.V. (Rose Plant), Ellen T. Paparozzi Jan 1989

Concetta Tm (Papconc) C.V. (Rose Plant), Ellen T. Paparozzi

Agronomy & Horticulture -- Faculty Publications

A new and distinct variety of rose plant of the hybrid tea rose class, which was originated as a sport of the rose Gabriella; characterized by its bright orange red, well-formed hybrid tea type blooms with dark velvet overtones on the outer edges of the open flower; disease resistant with everblooming habit and outstanding pot forcing characteristics.


Tissue Culture In Rice (Oryza Sativa L. Subsp. Japonica Var. Lemont), Young M. Woo Jan 1989

Tissue Culture In Rice (Oryza Sativa L. Subsp. Japonica Var. Lemont), Young M. Woo

Masters Theses

The purpose of this study was to obtain callus induction and subsequent plantlet regeneration from various explants of rice (Oryza sativa L. subsp. japonica var. Lemont). Callus induction occurred from the somatic cells of ovary wall, immature and mature embryos, immature endosperm, stem nodes, and seedlings. Plantlets were regenerated from embryo-, endosperm-, and stem node-derived calli on differentiation media. Stem nodes were the most responsive to callus induction. Requirements for optimal callus formation and plantlet regeneration differed from each culture. The study investigated the effects of cold treatment of explants, initial culture in darkness, media, and subculture for individual explant ...


The Pros And Cons Of Organic Gardening, Linda Naeve, Donald Lewis Jan 1989

The Pros And Cons Of Organic Gardening, Linda Naeve, Donald Lewis

Entomology Publications

"Organic gardening" or "organic farming" is a term that has received a lot of media and consumer attention in recent years. The term is used quite vaguely to describe different cultural systems for growing plants. A simple and clear definition of organic gardening is the enrichment of a garden soil with naturally-occurring plant foods and the control of garden pests (insects, diseases and weeds) by cultural, mechanical and biological methods.