Plant Sciences Commons^™

Resin Volatiles Of Eastern Hemlock Induced By Its Non-Native Herbivores, Joshua D. Pezet

Masters Theses 1911 - February 2014

Eastern hemlock (Tsuga canadensis) is in decline because of infestation by the invasive hemlock woolly adelgid (Adelges tsugae; ‘HWA’) and, to a lesser extent, the elongate hemlock scale (Fiorinia externa; ‘EHS’). Many conifers respond to insect herbivory by inducing oleoresin-based defenses, however it is unknown whether eastern hemlock is capable of this inducible response. We conducted a plantation setting study of artificially infested saplings to determine if feeding by HWA or EHS induces changes in the tree’s volatile chemistry. The induced changes in volatiles we found were unlike the terpenoid-based defenses of related conifers. Only HWA feeding …

Growth And Establishment Of Newly Planted Street Trees, Alexander R. Sherman

Masters Theses 1911 - February 2014

Developing quantified establishment period estimates for newly planted trees will help set realistic goals for plant performance in the urban landscape. Nine years of tree planting records obtained from the city of Boston, MA and the town of Brookline, MA were used to derive samples of trunk caliper for hedge maple (Acer campestre), London planetree (Platanus x acerifolia), and red oak (Quercus rubra). Several site characteristics were measured to identify effects on newly planted tree growth.

Breakpoint estimates of the piecewise regression models fell at 4 years and 6 years for London planetree and …

Evaluation The Nitrogen Needs And Efficiency Of Rizhobia Strains To Provide Nitrogen To Chipilin (Crotalaria Longirostrata Hook. And Arn.), Fatima Del Rosario Camarillo Castillo

Masters Theses 1911 - February 2014

EVALUATION THE NITROGEN NEEDS AND EFFICIENCY OF RHIZOBIA STRAINS TO PROVIDE NITROGEN TO CHIPILIN (Crotalaria Longirostrata HOOK. AND ARN.)

FEBRUARY OF 2013

FATIMA DEL ROSARIO CAMARILLO CASTILLO, B.A., AUTONOMOUS UNIVERSITY OF CHAPINGO

M.A., UNIVERSITY OF MASSACHUSETTS AMHERST

Directed by: Professor Francis X. Mangan

Chipilin (Crotalaria Longirostrata) is a leguminous plant native to Central America and Southern Mexico and used in the preparation of traditional dishes in this region. Starting in 2009, farmers in Massachusetts have been growing chipilin with a weekly production of 800 kg∙ha^-1. However, as much as 300 kg∙ha^-1 of nitrogen has been …

Purification And Characterization Of Novel Nucleases From A Thermophilic Fungus, Kyle S. Landry

Masters Theses 1911 - February 2014

A thermophilic fungus was isolated from composted horse manure. The organism was as a Chaetomium sp. by sequencing the highly conserved ITS region of the fungus and comparing to known regions in a genomic database and was referred to as TM-417. TM-417 was found to have an optimal growth temperature of 45 ^oC and an optimal pH of 7.0. An extracellular DNase and RNase was found to be produced by the isolate and were purified 145.58-fold and 127.6-fold respectively using a combination of size exclusion chromatography and a novel affinity membrane purification system. The extent of purification was determined …

Rhythmic Growth And Vascular Development In Brachypodium Distachyon, Dominick A. Matos

Masters Theses 1911 - February 2014

Plants reduce inorganic carbon to synthesize biomass that is comprised of mostly polysaccharides and lignin. Growth is intricately regulated by external cues such as light, temperature, and water availability and internal cues including those generated by the circadian clock. While many aspects of polymer biosynthesis are known, their regulation and distribution within the stem are poorly understood. Plant biomass is perhaps the most abundant organic substance on Earth and can be used as feedstock for energy production. Various grass species are under development as energy crops yet several of their attributes make them challenging research subjects. Brachypodium distachyon has emerged …

Development Of A Cytosolic Ph Reporter For Tobacco By2 Cells, Michael E. Urbanowski

Masters Theses 1911 - February 2014

The regulation of pH is a critical homeostatic function of plant cells. In addition to acting as the primary cationic species responsible for energizing the plasma membrane, protons likely act as an important regulator and messenger. Despite this importance, few studies have thoroughly described cytosolic pH patterns as the plant cell progresses through the cell cycle. To investigate pH in plant cells, I chose Nicotiana tabacum (tobacco) Bright Yellow-2 (BY-2) cells as a model system. My research has two aims. First, I will measure and report the interphase cytosolic pH of BY-2 cells. Next, I will assay the cytosolic pH …

Comparative Genome Analysis Between Agrostis Stolonifera And Members Of The Pooideae Subfamily Including Brachypodium Distachyon, Loreto P. Araneda

Masters Theses 1911 - February 2014

Understanding of grass genome structure and evolution has been significantly advanced through comparative genomics. The genomes of most cool-season forage and turf grasses, belonging to the Pooideae subfamily of the grasses, remain understudied. Creeping bentgrass (Agrostis stolonifera) is one of the most important cool-season turfgrasses due to its low mowing tolerance and aggressive growth habit. An RFLP genetic map of creeping bentgrass using 229 RFLP markers derived from cereal and creeping bentgrass EST-RFLP probes was constructed for a comparative genome analysis. This genetic map was compared with those of perennial ryegrass, oat, wheat, and rice. Large-scale chromosomal rearrangements …

Examination Of The Association Between In Vitro Propiconazole Sensitivity And Field Efficacy Among Five Diverse Sclerotinia Homoeocarpa Populations On Turfgrass, James T. Popko Jr.

Masters Theses 1911 - February 2014

Sclerotinia homoeocarpa F.T. Bennett, the causal agent associated with dollar spot, is a common and economically challenging turfgrass disease in North America. Acceptable turfgrass quality requires the optimization of cultural practices and the judicious use of fungicides. Sclerotinia homoeocarpa causes significant damage to turfgrass swards from May to October annually, therefore, requiring multiple fungicide applications to maintain satisfactory turfgrass quality throughout the growing season. Sterol demethylation inhibitor (DMI) fungicides are among the most widely used in the United States and frequent use has led to the development of fungicide resistance to the DMI fungicide class. The precise mechanism of DMI …

Spatial Variation And Tradeoffs In Species Interactions, Holly L. Bernardo

Masters Theses 1911 - February 2014

The geographic mosaic theory of coevolution predicts that spatial differences in species interactions result in a patchwork of evolutionary hot and cold spots across a landscape. We used horsenettle (Solanum carolinense L.), a perennial weed with a diverse insect community found in old fields and meadows, to examine local adaptation and resource-mediated selection. The goals of this study were to (1) determine the potential for a selection mosaic by identifying local adaptation through trait-interaction matching with herbivores, pollinations and plant competitors, and (2) determine the potential for indirect selection through resource allocation tradeoffs. The potential for local adaptation was determined …

Use Of Short-Term Floods As An Additional Management Strategy For Controlling Dodder (Cuscuta Gronovii Willd.) In Commercial Cranberry Production, James M. O'Connell

Masters Theses 1911 - February 2014

Dodder (Cuscuta gronovii Willd.) is a weed of serious concern to cranberry (Vaccinium macrocarpon Ait.) growers. It develops vigorously and has a long-lived seed bank. Cranberries are a perennial crop and therefore strategies available to growers of annual crops are not practical. Herbicides, the primary management tool for dodder, although effective, have a narrow window of application and extended seedling emergence after applications can result in escapes. This project examined the effect of water temperature on dodder seed germination and the use of short-term floods (less than 72 hr) for dodder management.

Experiments investigated the effect of water temperature on …

Nitrogen Dioxide In The Urban Forest: Exposure And Uptake, Tanner B. Harris

Masters Theses 1911 - February 2014

Nitrogen dioxide (NO2) levels were measured inside and adjacent to canopies of urban trees in Springfield, MA, over two growing seasons. Nitrogen dioxide levels were consistently and significantly higher inside tree canopies compared to levels outside. During the second growing season, ozone (O3), temperature, and relative humidity (RH) were also measured using samplers co-located with the NO2 samplers. Ozone levels were significantly lower inside the canopy whereas temperatures were higher inside the canopy, and RH was not different between inner and outer canopy locations. The results corroborate theoretical models predicting elevated NO2 and depressed O3 levels inside tree canopies based …

Bolivia's Coca Headache: The Agroyungas Program, Inflation, Campesinos, Coca And Capitalism In Bolivia, John D. Roberts

Masters Theses 1911 - February 2014

Bolivia in the 1980s was wracked by monetary inflation approaching levels of the German Weimar Republic. Immediately following this time of great financial crisis in Bolivia, the U.N. founded a project through the U.N.D.P. to encourage peasant farmers in Bolivia to switch from growing coca (the plant used manufacture cocaine) to growing other cash crops for market. This crop substitution and development program, called the Agroyungas Project, lasted from 1985 to 1991 and is the focus of this study. While many U.N. pundits and journalists considered the program’s initial small successes promising, it has been considered since its conclusion to …

Assesment Of Ammonia Volatility From Fall Surface-Applied Liquid Dairy Manure, Katie Campbell-Nelson

Masters Theses 1911 - February 2014

Ammonia emissions from dairy and livestock operations are of significant environmental and human health concern in the United States. Conservation of ammonia from fall surface-applied manure could benefit farmers by retaining nitrogen for use by crops in the spring growing season. The primary goal of this research was to investigate a management strategy for mitigating ammonia volatility from cow manure at the time of field application with no incorporation in the fall before snow fall. The hypothesis is that application of manure in cooler fall temperatures will slow the rate of ammonia volatilization. The objective was achieved by measuring temperature …

Functional Analysis Of Receptor-Like Kinases In Pollen-Pistil Interactions In Arabidopsis Thaliana, Mini Aggarwal

Masters Theses 1911 - February 2014

Rac/Rop GTPases are molecular switches in plants that control the growth of polarized cells such as pollen tubes and root hairs, differentiation, development, actin dynamics, production of reactive oxygen species (ROS) and disease resistance. These small GTPases are activated by guanine nucleotide exchange factors (GEFs) that replace GDP for GTP and are referred to as RopGEFs in plants. To identify upstream components of the RopGEF regulated signaling pathways, GEF1 from Arabidopsis thaliana was used as a bait to screen a seedling cDNA library in a yeast two-hybrid system. This yielded members of a small family of the Catharanthus roseus Receptor-like …

Identification Of Pmt, Tr1, And H6h Gene Polymorphism And Tropane Alkaloid Chemotypes In Hyoscyamus Niger L. (Black Henbane), Lawrence Kramer

Masters Theses 1911 - February 2014

No abstract provided.

The Tanning Principles Of Plants, Frederic J. Smith

Masters Theses 1911 - February 2014

The tanning or astringent principles are widely distributed in plant life and infusions of those parts rich in tannin have long been used in the art of converting animal hides into leather.

Five handwritten pages plus a three page typed copy.