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Articles 1 - 12 of 12

Full-Text Articles in Life Sciences

Muskrat Population Dynamics And Vegetation Utilization: A Management Plan, Thomas R. Mccabe, Michael L. Wolfe Aug 1980

Muskrat Population Dynamics And Vegetation Utilization: A Management Plan, Thomas R. Mccabe, Michael L. Wolfe

Aspen Bibliography

Muskrat (Ondatra zibethicus) populations are located in extensive marshes that are managed either privately or by state or federal refuge personnel. Maintenance of a balanced muskrat population is important to marsh management, therefore necessitating accurate density estimates. Feasibility of a vegetational utilization index as a reliable population indicator is being tested at Fish Springs NWR, Utah.


Determination Of The Temperature Response Curves For Abscisic Acid And Its Derivatives In Economically Important Horticultural Crops, Jaleh Daie May 1980

Determination Of The Temperature Response Curves For Abscisic Acid And Its Derivatives In Economically Important Horticultural Crops, Jaleh Daie

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Part I

Four-week old tomato (Lycopersicon esculentum Mill.) seedlings were exposed to different constant temperatures of 15, 25, 35, or 45 C. To determine the effect of temperature on Abscisic Acid (ABA) young and old leaves were harvested at 0, 6, 12, 24, or 48 h and free, hydrolyzable and total ABA were measured using gas liquid chromatographic methods. Temperature had a significant effect on free, hydrolyzable and total ABA in both young and old leaves. Time had a significant effect as a cubic function on all ABA measurements in old leaves but in young leaves a significant effect …


Ultrastructural Localization Of Solanidine In Potato Tubers, Shau-Ron Han May 1980

Ultrastructural Localization Of Solanidine In Potato Tubers, Shau-Ron Han

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Solanine, the green substance in potato, Solanum tuberosum L., tubers, is a toxic glycoalkaloid that is a potential human health hazard. To control the formation of this glycoalkaloid a greater understanding of its site of synthesis is needed. Labelling of solanidine, a direct precursor in the biosynthesis of solanine, with digitonin may indirectly locate the site of solanine synthesis in tubers. A study using ultrastructural cytochemical techniques was initiated to explore this possibility.

Sprouted tips and peridermal complex (periderm and cortex) tissue were fixed three different ways: (1) glutaraldehyde only, (2) osmium tetroxide and glutaraldehyde, and (3) glutaraldehyde-osmium tetroxide-digitonin mixture. …


Effects Of Host Plant Patch Size And Surrounding Plant Type On Insect Population Dynamics, Lynn A. Maguire May 1980

Effects Of Host Plant Patch Size And Surrounding Plant Type On Insect Population Dynamics, Lynn A. Maguire

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of the present study was to investigate how plant spatial patterns and insect behavior interact to influence the population dynamics of insects using the plants. The study included three phases: l) field experiments using collards (Brassica oleracea) and the crucifer insect fauna; 2) simulation models representing the population dynamics of an insect herbivore as functions of insect dispersal behavior and host plant patch size; and 3) model-field syntheses integrating model predictions and field variability estimates to choose an appropriate spatial scale for future field experiments or applications.

In field experiments on surrounding plant type, collards were …


Chlorophyll Fluorescence Probe Of Ultraviolet-B Photoinhibition Of Primary Photoreactions In Intact Leaves, Robert S. Nowak May 1980

Chlorophyll Fluorescence Probe Of Ultraviolet-B Photoinhibition Of Primary Photoreactions In Intact Leaves, Robert S. Nowak

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Damage to primary photosynthetic reactions caused by environmental stress can be assessed by measurement of chlorophyll fluorescence induction in intact leaves. This approach was applied in studies of ultraviolet-B photoinhibition of photosynthesis in Pisum sativum L. and Rumex patientia L. leaves. At ultraviolet-B dose rates insufficient to cause inhibition of net photosynthesis, changes in the magnitude of fluorescence transients did occur, which suggested direct effects on chloroplast pigments in Pisum and inhibition of photosynthetic electron transport between the photosystems in both species. Leaves of these two species subjected to a much higher dose rate had a significant reduction of net …


Nongame Birds Of The Rocky Mountain Spruce- Fir Forests And Their Management, Kimberly G. Smith Jan 1980

Nongame Birds Of The Rocky Mountain Spruce- Fir Forests And Their Management, Kimberly G. Smith

T.W. "Doc" Daniel Experimental Forest

Spruce-fir forests in the Rocky Mountains consist mainly of Engelmann spruce and subalpine fir. The breeding avifaunas in these forests show remarkable consistency in composition along a latitudinal gradient from Montana to Arizona and New Mexico, and with avian communities in the Hudsonian life zone in Washington, Oregon, and California. Woodpeckers, corvids, and seed-eating finches are the most common components. Only the Golden Eagle and a few other raptors are threatened or endangered. Few species winter in these high mountain forests. The distribution of many species is controlled primarily by the vegetation physiognomy, a variable under the control of the …


Spider Community Organization : Seasonal Variation And The Role Of Vegetation Architecture, Cynthia L. Hatley, James A. Macmahon Jan 1980

Spider Community Organization : Seasonal Variation And The Role Of Vegetation Architecture, Cynthia L. Hatley, James A. Macmahon

Green Canyon Environmental Research Area, Logan Utah

The relationship between vegetation architecture and spider community attributes were examined in a big sage community. Spiders were separated into guilds using similarities of species' hunting behavior. Shrub architecture was experimentally manipulated in the field by either clippings 50% of the shrub's foliage to decrease foliage density or tying together a shrub's branches to increase foliage density. Shrub perturbations resulted in changes in the number of spider species, spider guilds and guild importance values. The number on spider species and guilds in the tied shrubs were significantly higher than those in the clipped or control shrubs sampled. Spider species diversity …


Infection Of Engelmann-Spruce Seed By Geniculodendron Pyriforme In Western North America, M W. Wicklow-Howard Jan 1980

Infection Of Engelmann-Spruce Seed By Geniculodendron Pyriforme In Western North America, M W. Wicklow-Howard

T.W. "Doc" Daniel Experimental Forest

Geniculodendron pyriforme Salt was identified and characterized by Salt (1974) as the fungus responsible for germination failure of Sitka spruce [Picea sitchensis (Bong.) Carr.] seed in Canadian and British forest nurseries. It was confirmed that the fungus isolated by Epners (1964) from seed of Pinus resinosa Ait., P. sylvestris L., P. strobus L., and Picea glauca (Moench.) Voss. in Canadian nurseries was the same (Salt, 1974). In addition, Salt (1970) demonstrated that the pathogen can infect seeds of western hemlock [Tsuga heterophylla (Raf.) Sarg.], lodgepole pine (Pinus contorta Doug!. ex Loud.), Japanese larch [Larix leptolepis (Sieb. and Zucc.) Gord.] and …


Ecology And Management Of Ruffed Grouse, Judith L. Landry Jan 1980

Ecology And Management Of Ruffed Grouse, Judith L. Landry

Aspen Bibliography

No abstract provided.


Propagation Of Quaking Aspen (Populus Tremuloides Michx.) From Root Cuttings, Karen Elizabeth Burr Jan 1980

Propagation Of Quaking Aspen (Populus Tremuloides Michx.) From Root Cuttings, Karen Elizabeth Burr

Aspen Bibliography

Lateral root cuttings were collected at five quaking aspen (Populus tremuloides Michx.) clones in Larimer County, Colorado on October 2, 1977 and May 30, 1978. The October 1977 root cuttings were stored eight months in air-tight plastic bags at 0 to 4°C. On June 1, 1978 the stored (October 1977) and the fresh (May 1978) root cuttings were planted in a greenhouse propagation bench. All sprouts that developed were allowed to grow on half of the 10-cm long root cuttings randomly selected as controls. On the remaining half of the root cuttings, designated pruned, all but the tallest sprout were …


Energy Values Of Nine Populus Clones, Terry F. Strong Jan 1980

Energy Values Of Nine Populus Clones, Terry F. Strong

Aspen Bibliography

Compares calorific values for components of nine Populus clones. The components include stem wood, stem bark, and branches. Also compares calorific values for clones of balsam poplar and black cottonwood parentages.


Northeastern Forest Experiment Station: Oak Site Index And Biomass Yield In Upland Oak And Cove Hardwood Timber Types In West Virginia, Harry V. Wiant, Michael S. Fountain Jan 1980

Northeastern Forest Experiment Station: Oak Site Index And Biomass Yield In Upland Oak And Cove Hardwood Timber Types In West Virginia, Harry V. Wiant, Michael S. Fountain

Aspen Bibliography

No abstract provided.