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Characteristics Of Nectar Production And Standing Crop In Campsis Radicans (Bignoniaceae)., Andrea Alexis Edge May 2010

Characteristics Of Nectar Production And Standing Crop In Campsis Radicans (Bignoniaceae)., Andrea Alexis Edge

Electronic Theses and Dissertations

We examined several aspects of nectar production in Campsis radicans to better understand how standing crop is affected and how production affects pollinator visitation. In all experiments, nectar and concentration of flowers were measured and total sugar was calculated. Flowers do not produce additional nectar unless nectar is removed, and it is not resorbed. Volume of standing crop and total sugar fluctuates throughout the day, whereas concentration remains constant. Age and time of day significantly affect regeneration of nectar and sugar. The number of removals did not significantly affect the amount of nectar or sugar regenerated; however, concentration declined significantly …


Assessing The Biological Condition Of Maine Streams And Rivers Using Benthic Algal Communities, Thomas John Danielson May 2010

Assessing The Biological Condition Of Maine Streams And Rivers Using Benthic Algal Communities, Thomas John Danielson

Electronic Theses and Dissertations

The purpose of this study was to test and develop algal methods of evaluating the condition of Maine streams and rivers. The primary objective was to develop a statistical model to predict attainment of Maine's aquatic life criteria for water quality classes A, B, and C. I collected 298 samples of algae on rocks from 193 locations across the state. The major pattern in species composition related to conversion of forests to urban, residential, and agricultural land uses. I calculated preferred environmental conditions of 236 algal taxa for 1) concentrations of nitrogen, phosphorus, and dissolved ions in the water, 2) …


Investigating Nectar Rhythms In Squash (Cucurbita Pepo): Effects On Honey Bee (Apis Mellifera) Foraging Behavior., Samuel David Boyd Dec 2009

Investigating Nectar Rhythms In Squash (Cucurbita Pepo): Effects On Honey Bee (Apis Mellifera) Foraging Behavior., Samuel David Boyd

Electronic Theses and Dissertations

Experiments were performed to investigate the influence of water availability on the diel patterns of nectar secretion (volume, concentration, sugar production) in male squash flowers as well as to discover what physical component of nectar honey bees use to trigger their time-memory. Squash plants were grown in the greenhouse and in the field under both constant and variable watering regimes. Throughout anthesis, nectar volume and sugar concentration were recorded. In the field, the temporal distribution of arrivals to squash was observed with and without blossoms present. In the greenhouse and in the field, squash flowers exhibit a consistent diel pattern …


Latex Of Sciadopitys Verticillata (Thunb.) Siebold And Zuccarini: Antibiotic Properties, Phytochemistry, And Inhibition Of Adventitious Rooting Of Stem Cuttings., David Ira Yates Aug 2006

Latex Of Sciadopitys Verticillata (Thunb.) Siebold And Zuccarini: Antibiotic Properties, Phytochemistry, And Inhibition Of Adventitious Rooting Of Stem Cuttings., David Ira Yates

Electronic Theses and Dissertations

Sciadopitys verticillata was subjected to three propagation treatments designed to inhibit coagulation of its latex-like sap at the cut ends of the stem cuttings. Twenty-four hour soaking in water prior to rooting hormone application significantly enhanced production of adventitious roots. Old wood stem cuttings from shade-grown trees rooted at higher proportions than stem cuttings collected from sun-grown trees. Height, age, and place of origin of the source trees were not important factors in successful rooting. Antibacterial activity against some human pathogens and soil bacterial species was detected in latex application trials but the antibiotic activity was not related to the …


Localization Of Expansin Expression During Adventitious And Lateral Rooting In Response To Auxin In Loblolly Pine, Fuyu Xu Jan 2002

Localization Of Expansin Expression During Adventitious And Lateral Rooting In Response To Auxin In Loblolly Pine, Fuyu Xu

Electronic Theses and Dissertations

Loblolly Pine is the most important and widely cultivated timber species in the southern United States. Due to its fast growth, it is extensively planted for lumber and pulpwood. Vegetative propagation will enhance gains from genetic improvement of tree species. Rooted-cutting is at present the most reliable non-somatic embryogenesis method for cloning specific genotypes. However, an abrupt decline of adventitious rooting capacity has hindered the application of vegetative propagation in loblolly pine. Unraveling the rooting mechanism may facilitate a way to overcome this barrier. Regulation of lateral and adventitious root formation by auxin has been demonstrated through the application of …


Characterization Of Biochelators, Membrane Redox Systems, And Quinone Reductases From Wood Degrading Basidiomycetes, Weihong Qi Dec 2001

Characterization Of Biochelators, Membrane Redox Systems, And Quinone Reductases From Wood Degrading Basidiomycetes, Weihong Qi

Electronic Theses and Dissertations

Biodegradation of wood by brown rot fungi is dependent upon a non-enzymatic system involving Fenton chemistry. Iron biochelators with molecular weights lower than 1kD are important components in this process. Phenolate biochelators drive a hydroxyl radical generating Fenton reaction by reducing ferric iron. Biochelators may be mineralized or alternately, in some cases oxidized biochelators may be regenerated via a quinone redox cycle. Electron donors for this postulated regeneration have not been identified. Extracellular cellobiose dehydrogenase has also been found to drive the Fenton reaction by generating ferrous iron and hydrogen peroxide. This research compared the production of biochelators and the …