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The Efficacy And Non-Target Impacts Of An Organic Disease Management System Containing Biostimulants Compared With Two Sulfur-Based Systems On Four Apple Cultivars In Vermont, Ann L. Hazelrigg

Graduate College Dissertations and Theses

Disease management in organic apple orchards in Vermont is focused on controlling diseases with sulfur fungicides. The objective of this two year study was to evaluate the target and non-target effects of an organic disease management system containing agricultural biostimulants compared to two sulfur-based systems on foliar and fruit diseases, pest and beneficial arthropods, tree growth, yield and fruit quality on four cultivars, `Ginger Gold', `Honeycrisp' and `Liberty' and `Zestar!'. Trees were arranged in a complete randomized design of five three-tree replications in a certified organic orchard. The two sulfur-based systems differed in the number of applications; in the third …

Top-Down And Bottom-Up Tools For Integrated Pest Management In Northeastern Hop Production, Lily Calderwood

Graduate College Dissertations and Theses

The demand for locally sourced hops from Northeastern microbreweries began the recent resurgence in local hop production. The farming community has increased acreage and improved the quality of hops grown and processed in the Northeast region over the past five years. There was a sharp increase in the number of Northeast hop producers from six in 2009 to over 175 in 2014. Hop growers in the Northeast are new to the crop and have limited experience with pest identification and management. This dissertation encompasses three research projects that were conducted over the 2012-2014 growing seasons. These projects were the first …

Analysis Of Function Of The Son1-Interacting Protein, Lnk2 In Arabidopsis Thaliana, Prince Kudjoe Zogli

Graduate College Dissertations and Theses

The Arabidopsis SON1 F-box protein was implicated in regulating a pathogen defense pathway, but its exact function in wild-type plants is unknown. As an F-box protein it was predicted that SON1 would assembles into a SON1-SCF ubiquitin ligase complex that recruits specific plant defense-related proteins for proteolysis. The yeast 2-hybrid assay was used to screen for potential substrates for a putative SON1-SCF ligase, leading to the identification of Arabidopsis LNK2 as a SON1-binding factor.

Comprehensive protein-protein interaction analysis has shown that the binding of SON1 to LNK2 protein is specific, because closely related, full-length Arabidopsis F-box proteins do not interact …

The Impacts Of Multiple Anthropogenic Disturbances On The Montane Forests Of The Green Mountains, Vermont, Usa, Carolyn Ann Pucko

Graduate College Dissertations and Theses

How and why species’ ranges shift has long been a focus of ecology but is now becoming increasingly important given the current rate of climatic and environmental change. In response to global warming, species will need to migrate northward or upward to stay within their climatic tolerances. The ability of species to migrate will determine their fate and affect the community compositions of the future. However, to more accurately predict the future extent of species, we must identify and understand their responses to past and current climatic and environmental changes. The first place change is expected to occur is within …

Role Of Heme Oxygenase In Modulating Expression Of Ros-Regulatory Enzymes In Medicago Truncatula, Parna Ghosh

Graduate College Dissertations and Theses

Heme Oxygenase (HO) is an enzyme universally found in animals, plants and microbes. In plants, the role of heme oxygenase in the synthesis of the phytochrome chromophore is well recognized and has been extensively studied; however its role in regulating reactive oxygen species (ROS) in plants is just beginning to be explored, particularly in legumes. Legumes interact with Rhizobium bacteria to form symbiotic nitrogen fixing nodules. ROS plays an important role in the development of roots as well as symbiotic nodules. In the model legume Medicago truncatula, ROS in the root is regulated in part by the LATD/NIP gene. …

Investigations Into Host-Specific Interactions And Local Adaptation In The Mycorrhizal Symbiosis, Jonathan Gonzalez

Graduate College Dissertations and Theses

Mycorrhizal fungi are soil-borne organisms that form symbiotic associations with the majority of land plants. These fungi gather and exchange mineral nutrients with plants for photosynthetically derived carbohydrates. Mycorrhizal fungi can also confer other benefits onto plants, e.g. defense against pathogens, improved water relations, tolerance to heavy metal toxicity and herbivory. The influence of mycorrhizal fungi on plant mineral nutrition and response to stress suggests that these organisms may have a role to play sustainable agriculture as well as in bioremediation and ecosystem restoration.

In contributing to this important research, I investigated host-specific interactions between mycorrhizal fungi and the sex …