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Tracking Environmental Trends In The Great Bay Estuarine System: An Examination Of Water Quality And Nuisance Macroalgal Blooms, Jeremy C. Nettleton

Doctoral Dissertations

Monitoring macroalgae populations is an effective means of detecting long term water quality changes in estuarine systems. To investigate the environmental status of New Hampshire's Great Bay National Estuarine Research Reserve, this study assessed the abundance/distribution of macrophytes, particularly Gracilaria and Ulva species, relative to eutrophication patterns; compared historical (1970s-1990s) and current algal biomass/cover at several sites; and compared Ulva and Gracilaria tissue N/P content to ambient and historical levels. Nitrogen and phosphorus testing revealed that the estuarine system has become eutrophic, and Ulva and Gracilaria biomass/cover have increased significantly. The percent cover of Ulva species, at seasonal maxima, was …

Eating Quality And Variability In Carotenoid Content And Profiles In Winter Squash And Sweet Potato, Jennifer Bonina Noseworthy

Doctoral Dissertations

A comprehensive study at the New Hampshire Agricultural Experiment Station (NHAES) of 16 winter squash cultigens (Cucurbita spp.), including inbred lines and open pollinated and F1 hybrid cultivars from the University of New Hampshire breeding program, was undertaken to determine dry weight (%DW), soluble solids contents (%SSC) and carotenoid contents of mesocarp tissue, major attributes for determining acceptable eating quality and nutritional content. Data were recorded at harvest, either 40 or 60 days after pollination (DAP), and after 30 and 60 days of storage at 14 °C. Carotenoid contents were determined spectrophotometrically and using high performance liquid chromatography (HPLC).

The …

Detection Of Trehalose In Porphyra Extracts Using Mass Spectrometry And Gas Chromatography-Mass Spectrometry, Ying Huo

Master's Theses and Capstones

It is known that trehalose helps many plants to survive under desiccated environment26. This property of trehalose has also been proposed to explain why Porphyra could survive desiccation when left on dry land for a long period of time25. However, after extensive study25, effort at identifying trehalose in Porphyra has been unsuccessful, leaving the question of whether trehalose really exists in Porphyra unanswered. In my thesis research, in collaboration with Dr. Anita Klein, I set out to use ion-trap mass spectrometry and gas chromatography coupled with mass spectrometry to identify and quantify the amount of trehalose in Porphyra extracts. Using …

The Status Of Five State-Listed Tidal Plant Species In New Hampshire With Emphasis On Potential Impacts Of Sea Level Rise, Lauren A. Kras

Master's Theses and Capstones

Tidal habitat in New Hampshire is restricted to 162 miles along coasts and estuaries. Limited area combined with anthropogenic impacts has caused 27 tidal plant species to be listed as threatened or endangered. In 2009 and 2010, the status of four threatened species: Eleocharis parvula, Samolus valerandi, Lilaeopsis chinensis , and Agalinis maritima and one endangered species Salicornia bigelovii was examined. To guide management and conservation, the historic and current distributions were compared and habitat features were determined. All five species were stable; however, S. valerandi and L. chinensis appear threatened by sea level rise and coastal squeeze as they …

Development And Evaluation Of Interspecific Cucurbita Maxima X Cucurbita Moschata Hybrids For Processing Squash, Jacob Uretsky

Master's Theses and Capstones

Interspecific hybrids derived from crosses of Cucurbita maxima Duch. x C. moschata Duch. have been utilized for taxonomic studies and introgression of advantageous traits, as well as for cultivation for fresh market squash. The present study involves the development and evaluation of C. maxima x C. moschata F1 hybrids for use as processing squash. Crosses were performed in the summers of 2009, 2010, and 2011 between inbred bush C. maxima breeding lines and vine C. moschata cultigens, and the resulting progeny were evaluated in the greenhouse and field in 2010 and 2011 for phenological growth traits, fruit traits, and fruit …

The Effect Of Superman, Agamous, And Acs-7 Gene Manipulations On Sex Determination In Transgenic Fragaria Vesca 'Hawaii-4', Xin Ding

Master's Theses and Capstones

Sex determination is of interest to plant breeders who transfer useful genes from wild relatives to the cultivated strawberry. The potential roles in sex determination of seven candidate genes, which included five SUPERMAN genes, the AGAMOUS gene, and the ACS-7 gene, were studied by re-introducing them into diploid strawberry as overexpression and RNAi constructs by Agrobacterium-mediated transformation. All of the transgenic calli expressed the GFP fluorescence marker. Among regenerated plants, some AGAMOUS-silenced plants transiently displayed a petalloid stamen or a vestigial petal phenotype, pointing to the AGAMOUS gene as negative regulator of A- and B-class genes according to the widely …

The Role Of Eelgrass (Zostera Marina L) Source Population Characteristics In Resilience To Stress And Restoration Success, Holly K. Bayley

Master's Theses and Capstones

Eelgrass (Zostera marina L.), an underwater marine flowering plant, has a high degree of morphological plasticity that allows it to survive and grow under a range of conditions and adapt to environmental changes. The degree to which resilience to stress varies among eelgrass populations is important for eelgrass conservation and management. Eelgrass plants from ten genetically differentiated populations were used in a mesocosm experiment where light availability and sediment organic content were manipulated. Productivity and survival were inhibited and morphology was altered by the stress treatments, with these plant responses differing significantly among populations. To further test differences in resilience, …