<p>The prevalence of allergic disease such as peanut (PN) allergy has increased within the last century. Environmental factors have been associated with an increased risk of developing allergic diseases. The severity of allergic diseases has also increased and clinical trials are investigating allergen-specific immunotherapy as a method to treat allergies. The purpose of this work was to identify a vaccine adjuvant that induced potent antigen-specific Th1 immune responses and determine its ability to reduce the development and severity of Th2- mediated allergic disease, using models of peanut hypersensitivity.</p><p>Three studies were performed. The first study compared a variety of vaccine adjuvants to identify a potent adjuvant with strong Th1-associated activity. This study verified that the Toll-like receptor (TLR) ligand CpG could induce potent Th1-associated immune responses. The second study tested the ability of environmental endotoxin levels and alum-adjuvanted vaccines to modulate the development of allergic disease using a mouse model of peanut allergy. Additionally, the TLR ligands, CpG and MPL, were combined with alum-adjuvanted vaccines to determine their ability to further impact allergic disease development. Results suggested that the addition of CpG to an alum-adjuvanted vaccine indirectly modified host immunity in a manner that decreased the development of PN-induced allergic disease. The last study evaluated the ability of CpG to reduce the severity of peanut allergy symptoms when combined with peanut in an immunotherapy formulation administered to peanut-hypersensitive mice. Nasal immunotherapy with PN + CpG but not PN alone or CpG alone reduced the severity of PN-induced anaphylaxis in hypersensitive mice. PN-hypersensitive mice treated with PN + CpG displayed an increased PN-specific IgG2c and IFN-γ responses. A reduction in allergic disease severity in PN-hypersensitive mice correlated with an increase in PN-specific IgG2c, IFN-γ and IL-10 responses and a reduction in PN-specific IL-13 responses, suggesting a shift from Th2 responses towards Th1 and/or T regulatory cell responses.</p><p>Taken together, the data obtained from these studies demonstrate the potent activity of CpG to induce antigen-specific Th1-associated immune responses and also reduce the severity of peanut-hypersensitivity in mice through direct and indirect association with peanut allergens.</p> / Dissertation

Using household level scanner data for 2006, 2007, and 2008, this dissertation consists of four studies, which present household- and market-level analyses of food safety issues concerning the 2007 Peter Pan recall on the demand for peanut butter at the category level and at the brand level. Findings of the first study suggested that the recall had a statistically significant positive effect on the demand for peanut butter at the category level. At the brand level, spillover effects were evident in that the demand for Jif was positively affected, while the demand for Skippy was negatively affected. The second study examined structural change in the demand for peanut butter using demand system models corresponding to the pre-recall and the post-recall periods. Matrices of own-price, cross-price, and expenditure elasticities were calculated for both recall periods, and upon comparison, there were statistical differences in the corresponding estimated elasticities. In general, most price elasticities in the post-recall period were larger in absolute value than the comparable elasticities in the pre-recall period. The third study investigated the impact of household socio-economic characteristics associated with choices to purchase peanut butter across the pre- and the post-recall periods. Four choice scenarios were no buy-no buy, buy-no buy, no buy-buy, and buy-buy. Socio-economic characteristics considered included age, employment, education, race, ethnicity, presence of male and/or female household head, region, age and presence of children in the household, household size, and income. While the results varied by brand, region was the socio-demographic characteristic that was consistently significant among the choice scenarios for the respective peanut butter brands. Conditional on households purchasing peanut butter in both the pre- and the post-recall periods, the final analysis examined the influence of the same aforementioned socio-economic variables as well as the change in the own price on the change in the quantity purchased. The results varied across brands, but the principal drivers of the conditional change in the quantity purchased were the change in the own price and the age and presence of children in the household.

Thesis (Ph. D.)--Columbia University, 1922. / Vita. Bibliography: 1 p. following p. 32.

Thesis (M.S.)--West Virginia University, 2009. / Title from document title page. Document formatted into pages; contains ix, 59 p. : ill. Vita. Includes abstract. Includes bibliographical references.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 61-67). Also available via the Internet.

Thesis (Ph. D.)--Columbia University, 1922. / Vita. Description based on print version record. Bibliography: 1 p. following p. 32.

Experiments were conducted to evaluate the management of thrips (Thysanoptera: Thripidae) in peanut and cotton and the interaction between thrips and tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), in cotton. Although management of thrips with foliar insecticides historically has not been recommended in peanut, the current study observed significant yield benefits from the management of thrips with foliar insecticides. This was especially evident when peanut plants were stressed from herbicide injury. In another experiment, significant differences were observed among cotton varieties in terms of their susceptibility to thrips injury. Finally, an interaction between thrips injury and tarnished plant bug injury in cotton was not observed in these studies. However, both thrips and tarnished plant bug caused significant yield losses in cotton. Results from these experiments will be important for improving current integrated pest management programs in both cotton and peanut.

Foliage feeding insects like fall armyworm (FAW) [Spodoptera frugiperda (J. E. Smith)], granulate cutworm (GCW) [Feltia subterranean (F.)], velvetbean caterpillar (VBC) [Anticarsia gemmatalis (Hübner)] and corn earworm (CEW) [Helicoverpa zea (Boddie)] in peanut (Arachis hypogaea (L.)) and their effects on canopy defoliation and the resultant yield loss is outdated and essentially non-existent in Mississippi. With the expansion of peanuts throughout the state since 2012, growers struggle to manage foliageeeding pests in peanut. The lack of current information regarding insect pressure and economic injury levels is troublesome; especially with newer, high yielding, disease resistant cultivars. Research was required to understand how peanuts respond to complete canopy removal at different times during the growing season. Consequently, we evaluated the severity of canopy defoliation causing significant levels of yield loss during key physiological growth periods. This information will assist growers and extension personnel streamline management decisions for canopy defoliation in peanut throughout Mississippi.

Studies were conducted in the field from 2020-2021 in peanut and cotton to optimize peanut growth and yield through prohexadione calcium application methods as well as weed control through increasing herbicide sites of action. These studies were established on multiple on-farm and small-plot locations in Mississippi. Prohexadione calcium studies concluded that following application of prohexadione calcium effects on yield and peanut growth were inconsistent. Neither varying application timing nor rate resulted in peanut yield that was different than when adhering to the label recommendations. Increasing sites of action studies concluded that broadleaf signalgrass and Amaranthus species control was optimized at four SOAs and two SOAs, respectively. Based on this study, the current recommendation of additional SOAs will not result in increased weed control.

Peanuts (<i>A. hypogaea</i>) are an economically important crop, a source of food allergies and a member of the South American genus <i>Arachis</i>. The eighty species of genus <i>Arachis</i> have been divided into nine sections. The largest, section <i>Arachis</i>, has been further subdivided into three genome groups. The current intuitive understanding of the evolutionary relationships among <i>Arachis</i> is based on morphological, geographic and cytogenetic data, but a comprehensive phylogenetic study for the genus is lacking. A total of 48 species representing all nine sections were used to reconstruct a phylogeny based on sequence information from plastid <i>trn</i>T-<i>trn</i>F and nuclear ITS genomic regions. Phylogenetic analysis resolved section <i>Extranervosae</i> at the base, followed by sections <i>Triseminatae</i> and <i>Caulorrhizae</i>. Two major terminal lineages were recovered. One is comprised of sections <i>Erectoides</i>, <i>Heteranthae</i>, <i>Procumbentes</i>, Rhizomatosae</i>, and <i>Trierectoides</i>, referred to here as group erectoides. The other is comprised of two major clades, arachis I (B genome, D genome, and aneuploid species) and arachis II (A genome species). The phylogenetic trees show that sequence data partially agrees with the relationships described in the monograph; however, some further investigation is necessary to clarify relationships within and among species of the two terminal lineages. In addition, the major allergen Ara h 2 from 12 wild species from across the genus was analyzed for mutations that could potentially produce a hypoallergenic ortholog. It was found that the evolution of the allergen mostly reflected the species phylogenies based on ITS and combined. The majority of substitutions and length variations were concentrated in the loop connecting helices H2 and H3. Section <i>Arachis</i> species tended to have larger H2-H3 loops, while those from other sections had shorter loops. The immunodominant epitopes #6 and #7, located within this loop, tended to contain mutations or were truncated among species outside of section <i>Arachis</i>. Dot immunoblots showed reduced IgE-binding to peptides representing portions of the H2-H3 loop from <i>A. guarantica</i> and <i>A. triseminata</i>. Orthologs from wild species have demonstrated that they could potentially contain variations of the allergen Ara h 2 that could be utilized to develop a safer peanut cultivar. / Ph. D.