Understanding And Developing Safer Sanitation Agents And Strategies In Food Production Environments, Pragathi Kamarasu

Doctoral Dissertations

Food is a primary resource for survival of human beings, and it is also one of the primary resources for spread of infectious diseases. When both these factors come together it does not only cause ill effects on our health but also causes a burden on the food and agricultural industry. Through the help of science, us researchers and scientists have always tried to reduce this burden. And I hope like a drop of water in the ocean in some way my research contributes towards this. According to WHO currently in 2023 there are about 1 in 10 people falling …

The Use Of Biological Soil Health Indicators To Quantify The Benefits Of Cover Crops, Alexander Wu

Masters Theses

Soils provide many essential functions that support the world. With a decline in soil health, these functions also decrease in efficiency, and can threaten the health of billions of people around the world. Typically, soil health tests do not use biological indicators, however microbes drive and perform vital functions to increase soil health. One way to increase soil health is through the use of cover crops to reduce soil erosion during fallow periods, increasing soil organic matter, as well as collecting nutrients from soil into their biomass. These cover crops are then terminated through various methods such as herbicides, disk …

Role Of Plasma Membrane Intrinsic Proteins (Pips) Subfamily And Sulfur Nanoparticle Interactions In Metalloids Transport And Tolerance/Sensitivity In Rice, Ahmed Gm Ali

Doctoral Dissertations

Plasma membrane intrinsic proteins (PIPs) are major intrinsic proteins (MIPs) with the ability to permeate water and small uncharged solutes as well as metalloids including arsenic (As), through the cell membranes. Arsenic is a highly toxic element that occurs naturally in the earth's crust or from anthropogenic activities with a severe poisonous effect on most living organisms. Rice, as the daily staple food for more than half of the world population, accumulates higher As contents than any other economic crop due to its growing conditions in flooded paddy fields. Members from the NOD26-like intrinsic proteins (NIP) subfamily of MIP were …

The Influence Of Cover Crop Termination Strategies And Supplemental Nitrogen On Sweet Corn Yield And Nitrogen Use Efficiency, Sachina Sunuwar

Masters Theses

Cover crops are instrumental in nutrient management and soil health. A field experiment was conducted from fall 2020 to summer 2021 to evaluate the efficiency of different cover crop termination techniques and supplemental nitrogen on sweet corn yield, ear quality and nitrogen use efficiency. The four termination types are herbicide and disk tillage (HDT), herbicide no-till (HNT), cultivation disk till (CDT), and roller crimped no-till (RCNT). These termination types were each divided into four different nitrogen treatment: 0%, 33%, 67% and 100% of the recommended doses (145 kg haˉ¹). Sweet corn yield was highest and % unfilled tip was lowest …

Screening For Binding Partners And Protein-Protein Interactions Of A Fungal Transcription Factor- Xdr1, Nishadi Punsara Gallala Gamage

Masters Theses

Clarireedia spp. (formerly Sclerotinia homoeocarpaF.T. Bennett) is the causal agent dollar spot, the most economically important turfgrass disease impacting golf courses in North America. The most effective strategy for dollar spot control is repeated application of multiple classes of fungicides. However, reliance on chemical application has led to resistance to four classes of fungicides as well as multidrug resistance (MDR). Fungi are known to detoxify xenobiotics, like fungicides, through transcriptional regulation of three detoxification phases: modification, conjugation and secretion. Little is known, however, of the protein-protein interactions that facilitate these pathways. Following next-generation RNA sequencing of Clarireedia spp., a …

Community Assembly And Stress Response Of Grassland Phyllosphere Bacteria, Emily Bechtold

Doctoral Dissertations

Grasslands are an important ecosystem with potential to help stabilize food security and reduce greenhouse gas levels. As global temperatures rise, weather patterns are predicted to drastically change. The resulting increase in intensity, duration, and frequency of drought in important grassland areas will not only affect agricultural production, but also increase grassland susceptibility to fire, disease, and soil erosion. Thus, developing ways to sustainably promote grassland health and production is essential to increase food security and reduce environmental strain. Microbes in the phyllosphere, or aerial surface of plants, promote host fitness through phytohormone and nutrient production, increased stress tolerance, and …

Habitat Associations Of Priority Bird Species And Conservation Value On Small, Diversified Farms In New England, Isabel Brofsky

Masters Theses

In recent decades, New England agriculture has become increasingly characterized by small, diversified farming operations with values deeply rooted in community and conservation. In sharp contrast to large-scale, high-intensity agriculture currently typified by the majority of North American farms, New England farmers commonly prioritize ecologically beneficial production practices such as reduced chemical inputs, integrated pest management (IPM), low tillage, cover cropping and crop rotation, and retention of natural habitats like woody hedgerows and herbaceous strips. Public support and demand for local, sustainable food, evidenced by the success of CSA (Community Supported Agriculture) in the region, has helped to bolster this …

The Effect Of Gap Spacing Between Solar Panel Clusters On Crop Biomass Yields, Nutrients, And The Microenvironment In A Dual-Use Agrivoltaic System, Kristen Oleskewicz

Masters Theses

Agrivoltaic (AV) systems are dual-use land systems that consist of elevated solar panels with crops grown underneath. They offer a solution to the increasing demand for food production and clean renewable energy. The main concern regarding AV systems is the reduced availability of light to crops below the panels. Research to date shows that AV systems are quite productive with total energy and crop production exceeding the outputs of either solar farms or crop production alone. Research also shows that solar panels affect the microenvironment below the panels. The research on AV systems so far considers altering panel density to …

Effects Of Fertilization And Drying Conditions On The Quality Of Selected Chinese Medicinal Plants, Zoe Gardner

Doctoral Dissertations

Demand for Chinese medicinal herbs in the U.S. is increasing and American acupuncturists and farmers are interested in domestic production of these plants. Little is known about the feasibility of production of these species outside of China. Four species of herbs were selected for cultivation trials. The purposes of this research were to evaluate the feasibility of cultivation of these species in the northeastern United States, to develop basic agronomic data for each species, and to determine the effects of nitrogen fertilizer on plant growth, yield, and secondary metabolites. Agastache rugosa, Schizonepeta tenuifolia, Leonurus japonicus, and Leonurus …

Surface-Enhanced Raman Spectroscopic Imaging Of Bacteria Within Fresh Produce In Situ, Michael Hickey

Doctoral Dissertations

The growth curves for E. coli O157:H7 (#043888) are reported. We make the case that the onset of stationary growth is the optimal point at which a bacteria culture is considered suitable for quantitative Raman analyses. The optimal conditions for 3-mercaptophenylboronic acid coating of bacteria cells is also reported. Fundamental drawbacks of the status-quo approach have been elucidated and overcome, based on measurable improvements to the experimental methodology. This approach is shown to be suitable for the evaluation of bacterial rinse-washing efficacy by means of Raman light-scattering. The data were compared to label-free applications and the measurable differences between each …

The Good, The Bad, And The Ugly: Pollinators As Vectors Of Mummy Berry Disease In Highbush Blueberry, Matthew Boyer

Doctoral Dissertations

Background: Many plants must balance the need for pollination services with mediating the risk of pollinator-vectored pathogens. Vaccinium corymbosum, highbush blueberry, is negatively affected by an insect-vectored, fungal plant pathogen, Monilinia vaccinii-corymosi (MVC), the cause of mummy berry disease, in which the asexual spore mimics pollen grains and is transferred from blighted tissue to flowers via pollinators, resulting in inedible, hardened fruits. Highbush blueberry plants require outcrossed pollen for maximum yield and fecundity. Therefore, yield of blueberry plants rely on a balance between adequate pollination service and disease avoidance. Approach: To explore the relationship between pollinator community and infection …

Apple Disease Forecasting Models: When Climate Changes The Rules, Elizabeth W. Garofalo

Masters Theses

With a changing global climate, plant pathologists must understand the impact aberrant weather events may have on the development of plant diseases. Fungal plant infections are largely dependent on temperature and precipitation, climate parameters that are predicted to change more in this century. Venturia inaequalis causes apple scab, one of the most destructive apple diseases of temperate growing regions. Temperature and precipitation drive apple scab infections and forecast models, which guide growers in efficient, effective fungicide applications. In some recent years in the Northeast, these models have failed to accurately predict when ascospores of this fungus are available to cause …

Combination Regimens Using Dietary Components For The Chemoprevention Of Colorectal Cancer And Inflammation, Christina Dimarco-Crook

Doctoral Dissertations

ABSTRACT COMBINATION REGIMENS USING DIETARY COMPONENTS FOR THE CHEMOPREVENTION OF COLORECTAL CANCER AND INFLAMMATION September 2018 CHRISTINA DIMARCO-CROOK, B.S., IMMACULATA UNIVERSITY M.S., DREXEL UNIVERSITY Ph.D., UNIVERSITY OF MASSACHUSETTS AMHERST Directed by: Professor Hang Xiao Dietary components have been found to effectively modulate multiple deregulated signaling pathways associated with the initiation and progression of carcinogenesis and inflammation in cellular and animal models. However, clinical studies have shown mixed results when examining the efficacy of individual dietary components, perhaps suggestive of the synergism that exists between multiple components within a particular food and the diet as a whole. Additional research is needed …

Screening Of Commercially Available Chlorine Based Sanitizers And Their Efficacy In Reducing Microbial Load Levels Of E. Coli O157:H7 At High And Low Organic Load Environments, Paola Martinez-Ramos

Masters Theses

The presence of postharvest sanitizers has shown to be an effective approach to reducing microbial cross contamination in agricultural washing operations. However, choosing an appropriate sanitizer can be challenging due to produce commodity, processing conditions and interference with organic load. Current research shows a wide variety of methods to mimic the organic load of vegetable processing conditions, with paddle mixing and blender as the most commonly used. Controlling and understanding the physiochemical properties of wash water is key in maintaining sanitizer efficacy. The effects of simulated wash water preparation method on the physiochemical properties were tested at 0 and 50 …

Impact Of Oyster Mushroom Mycelium On The Growth Of Kale And Forage Radish, Levi Lilly

Masters Theses

Saprophytic fungi can be paired with companion crops in interplant systems to increase production efficiency. However, fungal species/strain, substrate, and inoculation rate can affect the growth of companion crops. This project investigated the viability of open-field mushroom production by interplanting three strains of Pleurotus ostreatus (Elm A, Elm B, and 8801) with kale (B. oleracea var. acephala) and forage radish (Raphanus raphanistrub sub. sativus), and measured the effect of interplanting on plant yield over two field seasons. In the field, Elm A showed an increase in plant yield at a low inoculation rate and decrease in …

Integrating Cover Crop Mixtures And No-Till For Sustainable Sweet Corn Production In The Northeast, Julie S. Fine

Masters Theses

Fall-planted forage radish (Raphanus sativus L. longipinnatus) cover crops have shown successful weed suppression and recycling of fall-captured nutrients. This research evaluated the nutrient cycling and weed suppressive benefits of forage radish cover crop mixtures to develop an integrated system for no-till sweet corn (Zea mays L. var rugosa) production that improves crop yield and soil health. Treatments included forage radish (FR), oats (Avena sativa L.) and forage radish (OFR), a mixture of peas (Pisum sativum subsp arvense L.), oats and forage radish (POFR), and no cover crop control (NCC). Subplots were assigned to …

Transposable Elements In Fusarium Oxysporum & Growth Inhibition Of Fusarium Oxysporum Using Pepper Extracts, Taylor Aguiar

Masters Theses

The following contains two projects focused on the fungal pathogen, Fusarium oxysporum. The first project was purely computational in the examination of transposable elements (TEs), which are mobile sequences with the ability to multiply and move in their host genome. In F. oxysporum, TEs such as miniature impala elements are associated with the secreted in xylem gene that are related to its virulence over its host. The F. oxysporum species complex can be utilized as a model system for the examination of TE content and TE expression during the infection cycle. To find whether TEs play a role …

Golfer Exposure To Pesticides, Jeffery Doherty

Doctoral Dissertations

There is concern among industry regulators, turfgrass managers, and the general public over human exposure to pesticides following their application to turfgrass. The residential aspect of turfgrass applications raises concerns about exposure to infants and children, as well as adults. To accurately determine the exposure of golfers to turfgrass pesticides, it is necessary to understand their transfer and absorption dynamics, as well as the routes of golfer exposure. Previous research has demonstrated that exposure to some turfgrass pesticides is at a level that would concern USEPA risk assessors using the USEPA Hazard Quotient (HQ) criteria (1). This current research used …

All Roads Lead To Weediness: Stories About Weedy Rice Origins, Weedy Genes And Weed Competitiveness, Zhongyun Huang

Doctoral Dissertations

Weedy rice (Oryza spp.), a weedy relative of cultivated rice (O.sativa), infests and persists in cultivated rice fields worldwide. Many weedy rice populations have evolved similar adaptive traits, considered part of the ‘agricultural weed syndrome’, making this an ideal model to study the genetic basis of parallel evolution. Using population genetics analyses of South Asian and US weedy rice, my research reveals multiple independent evolution events giving rise to weed groups in the two geographic areas. Weeds in South Asia have highly heterogenous genetic backgrounds, with contributions from both cultivated varieties (aus and indica) …

Comparative Transcriptome Analysis Of Wild Tomato Species During Fruit Development, Altynay Zhanayeva

Masters Theses

Fleshy fruits in different species can display large variation in color. A link between fruit color and seed dispersal success is suggested by previous studies showing that high intensity of fruit color increases the visitation rate in seed-dispersing birds. Wild tomato species (Solanum spp.) are excellent model organisms for research on genetic basis of differential fruit color development during the ripening process. Despite polymorphism in fruit color, all tomato species have yellow flowers due to accumulation of carotenoid pigments, which suggests that the carotenoid pathway is intact. Thus, regulatory changes controlling enzymes activity during fruit maturation are likely …

Novel Advancements For Improving Sprout Safety, Kyle S. Landry

Doctoral Dissertations

All varieties of bean sprouts (mung bean, alfalfa, broccoli, and radish) are classified as a “super-food” and are common staples for health conscious consumers. Along with the proposed health benefits, there is also an inherent risk of foodborne illness. When sprouts are cooked, there is little risk of illness. The purpose of this dissertation was to explore novel techniques to minimize or prevent the incidence of foodborne illness associated with the consumption of sprouts. Three areas were investigated: 1) the use of a biocontrol organism, 2) the use of a novel spontaneous carvacrol nanoemulsion, and 3) the influence of the …

Cover Crop And Nitrogen Fertilizer Management For Potato Production In The Northeast, Emad Jahanzad

Doctoral Dissertations

Potato (Solanum tuberosum L.) rates fourth among the world’s agricultural products in terms of production volume and human consumption and worldwide demand for potatoes will exceed that of rice, wheat, or corn by 2020. Potato consumption has been a major part of the North American diet since early in the 17^th century and as a dominant arable crop in the Northeastern United States. There are over 2700 potato fields in the Northeast United States and potato growers often over apply nitrogen (N) fertilizer to ensure against loss of yield. High mobility of nitrate form N fertilization in the …

Effects Of Overexpression Of Sap12 And Sap13 In Providing Tolerance To Multiple Abiotic Stresses In Plants, Parul R. Tomar

Doctoral Dissertations

Environmental stresses are the one of the main reasons for the decline of crop production worldwide. In the past years, a major focus has been on improving plant species and their tolerance towards these stresses but not much has been achieved because of the limited knowledge of the gene/network of genes that might be involved in providing tolerance to such multiple abiotic stresses. Recently, members of Stress Associated Protein (SAP) family in plants have been shown to impart tolerance to multiple abiotic stresses. There are 14 SAP genes in Arabidopsis thaliana and these proteins contain A20, AN1 and C2H2 zinc …

Evaluation Of Leafy Green Species Popular Among Ethnic Groups For Production And Markets In The Northeastern Usa, Ricardo A. Orellana

Doctoral Dissertations

ABSTRACT

Rnai Mediated Silencing Of Cell Wall Invertase Inhibitors To Increase Sucrose Allocation To Sink Tissues In Transgenic Camelina Sativa Engineered With A Carbon Concentrating Mechanism, Joshua Zuber

Masters Theses

Plant invertases are a class of proteins that have enzymatic function in cleaving sucrose to fructose and glucose. Cell wall invertase, located on the exterior of the cell wall of plant cells, plays a key role in the unloading of sucrose from the apoplast to the sink tissues. Cell wall invertase interacts with an inhibitor, cell wall invertase inhibitor, post-transcriptionally to regulate its activity. The inhibitor is constitutively expressed in pollen development, early developing seeds, and senescing leaves: indicative of sucrose allocation being a limiting factor at these stages of development. We introduced algal bicarbonate transporters LCIA/CCP1 to Camelina sativa …

Effects Of Early Spring And Preventative Snow Mold Fungicide Applications On Dmi Sensitive And Insensitive Populations Of Sclerotinia Homoeocarpa, Marvin D. Seaman

Masters Theses

Dollar spot, caused by the pathogen S. homoeocarpa (F.T. Bennett), is a common disease that infects a wide variety of turfgrasses all over the world. Yet it is significant problem on golf course putting greens and fairways consisting of creeping bentgrass (Agrostis stolonifera L.) and annual bluegrass (Poa annua L.). It is active in a wide variety of environmental conditions ranging from 16-30˚C but favors warm, humid days, followed by cool nights. Sclerotinia homoeocarpa overwinters as dormant mycelium in dead plant tissue. In the spring, germinating mycelia begin to infect leaf blades causing foliar lesions, which then spread …

Efficient Irrigation For Recreational Turfgrass In New England: Evapotranspiration And Crop Coefficients, James W. Poro

Masters Theses

As water demand increases it will become more imperative for golf course superintendents, landscape managers, and other industry professionals to improve water use efficiency in the management of recreational turfgrass. Scheduling irrigation according to actual turfgrass evapotranspiration rates (ET_T) is an integral component of efficient irrigation practices. Impracticality of field derived ET_T for industry use, however, directs the need of weather station derived reference (predicted) evapotranspiration (ET₀). To accurately predict (estimate) ET_T of turf and other crops, scientifically derived landscape (crop) coefficients (K_c values) are used in conjunction with mathematical models that incorporate …

Production, Marketing, And Handling Practices To Export Mcintosh Apples To Central American Markets, Mildred L. Alvarado Herrera

Doctoral Dissertations

Latin America offers a marketing opportunity for fresh produce, since many countries are entering into global integration and international trade as part of their portfolio of economic growth. However, to take full advantage of these opportunities, many questions associated with the implementation of marketing approaches, fresh produce quality retention, and profitability need be answered before undertaking this business opportunity. When it comes to developing countries such as those in Central America, and in particular - El Salvador, Honduras, and Guatemala - language, culture, technology, competitiveness, regulations, poverty, and other barriers become challenges to enter these markets successfully. In order to …

Use Of Flame Cultivation As A Nonchemical Weed Control In Cranberry Cultivation, Katherine M. Ghantous

Open Access Dissertations

Cranberry (Vaccinium macrocarpon Ait.) is a woody perennial crop that can remain productive for decades. Competition for resources between cranberries and weeds can depress cranberry farm yields, resulting in large annual crop losses. Renewed interest in reducing chemical inputs into cranberry systems has provided the motivation to evaluate methods, such as flame cultivation (FC), as potential nonchemical options for weed control. Also known as thermal weeding, FC exposes plants to brief periods of high temperature that causes the water in the plant tissue to expand rapidly, rupturing plant cells and leading to necrosis. Various FC methods have been used …