Plant Biology Commons^™

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, submerged …

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 County plants occur in two …

Bulletin 4133 - Fungal Diseases Of Pasture Legumes In Western Australia, M. J. Barbetti

Bulletins 4000 -

Subterranean clover (Trifolium subterraneum L.) is the most important annual pasture legume in Western Australia, forming the basis of some 6.5 million ha of annual pastures. The success of subterranean clover may be attributed to its ability to increase soil fertility as a consequence of nitrogen fixed, to withstand heavy grazing, to control soil erosion and, with some cultivars, to tolerate waterlogging. Fungal diseases have been a major limitation to the productivity of subterranean clover, affecting both the amount of plant matter and the quantity of seed produced.

Annual medic (Medicago spp., in particular M. polymorpha L.) is also an …

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 plants, …

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

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 Virginia …

Bulletin No 4146 - Commercial Production Of Pawpaws In Western Australia, J. R. Burt, B. L. Toohill

Bulletins 4000 -

The papaw (Carica papaya L.) is a native plant of Central America. It produces its highest yields of good quality fruit in tropical regions.

The tree is short-lived and rarely produces crops for more than two or three years. It is quick growing and soon reaches a maximum height of 5 to 7 m. It is usually unbranched, but may branch after either injury to the top or cutting back.

The Effects Of Potassium Cations On The Germination Of Phytolacca Americana, Karen Michelle Smith

Honors Theses

Phytolacca americana, a plant species of eastern North America, is widely known as a plant of multiple uses in traditional medicine, a source of contemporary research compounds, and as a pot herb when correctly prepared for human consumption. Experimental conditions that promote rapid laboratory germination and the role of chemical factors in the germination process are being investigated in P. americana. The role of potassium ions in plant metabolism, especially the process of seed germination, is reviewed. Experiments were designed, the results of which are presented and discussed, to determine (1) the effect of exogenously applied salts of K+ on …

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 Research

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

Life Sciences Faculty Research

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 H2O …

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 Research

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 knowing …

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 …

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.

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 how …

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.

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 …

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 …

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.

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 …

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 …

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.

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 …

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 areas (12 x 30 m) was evaluated in ten randomly …

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 …

Introducing Onslow, Western Australian Department Of Agriculture

Grain and other field crops published reports

Onslow Barley........ a new breed of barley for the southern high rainfall areas (see map VH,H4 &H5). Suited to May plantings, Onslow is the first barley developed specifically for the long growing seasons in these areas.

For the first time barley growers have a variety designed for those 4 t/ha plus yields which research shows are possible with early sowing.

Onslow is the first of a new breed of barley cultivars developed in Western Australia specifically for the southern high rainfall areas which have a long growing season.

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

Department of Agronomy and 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.