Life Sciences Commons^™

Sources Of Variability In Agronomic Weed Seed Predation: Time, Space, Habitat, And Hyperpredation, Sonja K. Birthisel

Electronic Theses and Dissertations

Weed seed predation is an ecosystem service that benefits farmers by decreasing seedbank inputs, thereby reducing weed pressure in subsequent growing seasons. Seed predation can be considerable, but is highly variable. Sources of variability may include time, space, habitat, and trophic interactions such as hyperpredation. Two experiments were conducted to measure the impacts of these sources of variability on weed seed predation rates in Maine mixed vegetable agroecosystems.

Chapter One of this thesis describes a series of landscape-level field experiments conducted to quantify the effects of time, space, and habitat on seed predation rates. Seed assays, with and without vertebrate …

Reverse Genetic Analysis Of A Cysteine Protease-Encoding Gene (Rd19a) Of Arabidopsis Thaliana In Relation To The Mechanism Of Resistance To The Piercing/Sucking Insect Myzus Persicae, Siobhan A. Cusack

Honors College

A recent study in Solanum bulbocastanum (a wild relative of the cultivated potato) aiming to identify potential genes involved in aphid and pathogen resistance mechanisms found that a homolog of the Arabidopsis thaliana cysteine protease gene RD19a is upregulated during aphid infestation. RD19a is upregulated in response to abiotic stresses such as drought and high salinity, and rd19a mutants show increased susceptibility to bacterial infection. In this study, Arabidopsis rd19a mutants and wild-type plants were subjected to aphid feeding to observe and compare the molecular, physiological and phenotypic responses. The aim was to further establish the proof of concept regarding …

Slow Food: From Farm To Healthy Body, Hannah L. Ruhl

Honors College

Slow Food is a movement devoted to the preservation and promotion of personal, environmental and community health through lifestyle changes which focus on good, clean and fair food. Good refers to food that is healthy and nutritious for the body. Food grown sustainably as in organic agriculture contains higher levels of beneficial compounds such as vitamins, minerals and phytochemicals. Clean food contains no toxic or harmful compounds that can cause detrimental effects on health. Pesticides and other chemicals are often used in food production; as a result they are found in the final product and are often detected in the …