OAKTrust :: Browsing by Author "Smith, C. Wayne"

Browsing by Author "Smith, C. Wayne"

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An analysis of navigational instruments in the Age of Exploration: 15th century to mid-17th century
(Texas A&M University, 2006-04-12) Swanick, Lois Ann; Smith, C. Wayne; Grider, Sylvia; Rosenheim, James
During the Age of Exploration, navigation evolved from a field filled with superstition into a modern science in Portugal, Spain, and England. The most common navigation instruments utilized and their subsequent innovations are discussed. The refinement of these instruments led to increased accuracy in cartography, safer shipping, and increased trade globally in the period. In order to have the most comprehensive collection of navigation instruments, I investigated 165 shipwrecks dated between 1500 and 1700. Each of these vessels have been located, surveyed, and/or excavated in whole or in part. A comprehensive list of these vessels, compiled for the first time, has been included. This thesis analyzes navigation-related artifacts recovered from 27 of these shipwreck sites. These instruments provide the basis to develop a typology for archaeologists to more closely date these finds. The navigation instruments recovered from the wreck of LaBelle (1686) are discussed in detail. These instruments and related historical documents kept by the navigator provide a more comprehensive picture of the instruments’ accuracy and usefulness. This thesis particularly focuses on the nocturnal/planisphere recovered from the site. This unique instrument is one of only four known to exist worldwide and remains accurate enough to be utilized today. Analysis by a modern astronomer has been included, as well as a partial translation of the common names for constellations inscribed on the instrument. These common names provide some important insights into the received knowledge of sailors and non-academic astronomy during this period. It is hoped that this thesis will be of assistance to archaeologists working to identify, study, and appreciate navigational instruments recovered from shipwrecks. With increased documentation and closer dating, these instruments will become a more valuable portion of the archaeological record.
Analysis of the Pass Cavallo shipwreck assemblage, Matagorda Bay, Texas
(Texas A&M University, 2004-09-30) Borgens, Amy Anne; Hamilton, Donny L.; Smith, C. Wayne; Alonzo, Armando
A survey conducted in February of 1998 located an anomaly originally believed to be the remains of L'Aimable. L'Aimable was one of four ships utilized by Rene-Robert Cavelier, Sieur de La Salle, for his voyage to colonize the Gulf Coast in 1684. The anomaly, a wrecked vessel with a heavy iron signature, was located outside the entrance to the historic pass into Matagorda Bay, Texas. Artifacts were extracted from the wreck site to aid in the identification of the vessel, which was subsequently determined to be more recent in origin. A preliminary examination of the artifacts indicates that the shipwreck dates to the first half of the 19th century. The survey recovered over two hundred artifacts. The assemblage of artifacts includes over 80 lead shot, over 40 examples of brass firearm furniture, over 15 firearm fragments, several pieces of copper sheathing, and iron bar stock. Almost two-thirds of the material is associated with small arms. The majority of the identifiable firearms are military arms of three patterns: the British Short Land Pattern, the British India Pattern, and the 1757 Spanish musket. Historical research has determined that these arms were circulating in Texas, New Orleans, and Mexico, as early as 1815. The British Pattern arms were both purchased for the Mexican army in the 1820s, and used by the British Infantry in the Battle of New Orleans in 1815. The 1757 Spanish musket was used chiefly by Spanish expeditionary forces in North America in the late 18th century. Evidence garnered from the artifacts suggest that the firearms were shipboard cargo onboard a small, wood-hulled sailing vessel that wrecked between the years 1815 and 1845. Archival and historical research isolated nine wreck candidates for this period. Historical research and artifact analysis suggest the Hannah Elizabeth as the primary candidate for this wreck site. The Hannah Elizabeth was a small merchant schooner from New Orleans laden with a munitions cargo for Texas troops stationed at Goliad. The vessel wrecked at the entrance of the historic Pass Cavallo while evading capture from a Mexican brig-of-war in November of 1835.
Analysis of the weight assemblage of Port Royal, Jamaica
(1995-05) Smith, C. Wayne; Hamilton, Donny Leon; Schmidt, H.; Grider, Sylvia Ann; Carlson, David Lee
The assemblage of weights recovered from excavations at Port Royal, Jamaica is the largest collection of seventeenth-century weights recovered from a single colonial site. On June 7, 1692, just shortly before noon, an earthquake shook the community of Port Royal and in a matter of minutes, due to a process known as liquefaction, approximately thirty-two acres of the colonial port community sank below the waters of Kingston Harbor. To date, 90 weights have been recovered from nautical and terrestrial excavations at the site. Many of these bear the stamps and ciphers of English trade guilds as well as owners marks and regal stamps of authority. Several weights in the collection also bear a mark in the shape of a dagger or sword, which is associated with the City of London. Bronze and lead weights bearing cipher stamps offer a unique opportunity for archaeological and historical investigation. Combining data from archaeological excavations with information from wills, inventories and data from comparative assemblage known as the Streeter Collection, will result in a multi disciplinary analysis of the weights collection that has the potential for contributing a great deal of information about local and long distance trade and commercial patterns in colonial Jamaica. From a micro perspective, this analysis will contribute to the broader understanding of life and economic activities within the excavated area of the colonial port community. From a macro perspective, analysis of the weights should corroborate reforms in English law regarding the economic necessity for standardization of weights. Analysis of weight iconography suggests differences in mind-set that may have contributed in placing England apart from other European countries, in an advantageous position to become a leading economic force in the seventeenth century. An in depth analysis of the weight collection associated with seventeenth-century Port Royal will draw many sources of data together, offering new perspectives on the colonial Jamaican process.
Bahamian ship graffiti
(Texas A&M University, 2005-02-17) Turner, Grace Sandrena Rosita; Smith, C. Wayne; Woodcock, David; Grider, Sylvia
The Bahamian archipelago covers over 5,000 square miles of the Atlantic Ocean at the northwestern edge of the Caribbean Sea. In the Age of Sail, from the late 15th to early 20th centuries, these islands were on major sailing routes between the Caribbean, Central America, and Europe. Bahamians developed life-ways using their islands’ location to their advantage. Archaeological evidence of the significance of shipping activity is quite lacking. This research aimed to help fill the void by documenting examples of ship graffiti throughout the Bahamas. Examples of ship graffiti were documented with photographs and tracings. The Bahamian examples all date to the 19th and 20th centuries, 100 years later than other examples from the Caribbean and North America. They are also unique in being incised into the stone surfaces of building walls, caves, stones on a hillside, even on a slate fragment. It is possible that ship graffiti were also engraved on wooden surfaces but these have not survived in the archaeological record. Images depict locally-built vessels such as sloops and schooners as well as larger, ocean-going vessels. Ship graffiti are at sites associated mainly with people of African heritage, another possible social grouping being persons of lower economic status. Graffiti details consistently indicate that the artists were familiar with ship construction and rigging. This analysis of ship graffiti gives some understanding of the significance of ships and shipping in the Bahamian economy.
Blood and water; the archaeological excavation and historical analysis of the Wreck of the Industry, a North-American transport sloop chartered by the British army at the end of the Seven Years' War: British colonial navigation and trade to supply Spanish Florida in the eighteenth century
(Texas A&M University, 2006-04-12) Franklin, Marianne; Hamilton, D.L.; Crisman, Kevin; Rosenheim, James; Smith, C. Wayne
In the 10-mer RNA duplex model system a 4-isocyano TEMPO spin-label is individually attached to one strand and two strands are annealed to measure distances. This methodology is limited to systems in which two oligonucleotides are annealed together. To circumvent this limitation and also to explore single-strand dynamics a new methodology was implemented, double spin-labeling. Double spin-labeled single-stranded RNA was investigated as a single-strand and within a duplex via MALDI-TOF-MS, EPR spectroscopy and RP-HPLC. A double spin-labeling strategy in this work will be applicable to large complex RNAs like Group I intron of Tetrahymena thermophilia. Captain Daniel Lawrence, was one of four sloops detailed to serve as a transport to supply the British Florida garrisons. The Industry ran aground on the bar outside of St. Augustine's harbour on May 6, 1764. The transport was carrying six-pound cannons, ammunition and artificer's tools. Further investigation of documents describing eighteenth-century trade and shipping to St. Augustine led to the discovery that the Lawrence family of sea captains provided a vital link between British New York and Spanish St. Augustine. An examination of the materials recovered from Site 8SJ3478 sheds light on exactly what a particular vessel carried during a period of transition in Florida's history.
A Comparison of Publicly Available QTL SSRS for MAS with Traditional Plant Breeding Selection Methods in Cotton
(2019-11-26) Ullrich, Alexandra Paige; Smith, C. Wayne; Magill, Clint; Hequet, Eric
Public breeding programs for upland cotton (Gossypium hirsutum) underutilize genotypic selection methods and specifically marker assisted selection for fiber quality selection. A previous study by Kari Hugie sought to analyze publicly available simple sequence repeat (SSR) markers in three diverse populations to quantify those that showed correlative trait stability in different backgrounds. Stable markers identified from that study, 6 for fiber bundle strength (FBS) and 6 for upper half mean length (UHML), as well as two additional markers identified by Dr. Fang of the USDA Louisiana Laboratory were then utilized to make selections in two G. hirsutum populations. Population 1 (TAM 11K-13 ELSU/Del Cerro//13P-54 ELSU) was of interspecific background and Population 2 (TAM 11K-13 ELSU/TAM06WE-621 ESU) was of intraspecific background. In 2016, both populations were grown at the Agrilife Research Center in College Station, Tx and individual plant selections were made separately on the basis of SSR marker number and phenotype for both FBS and UHML to form populations divergent for the trait of interest. Selections were planted in progeny rows in 2017 and fiber samples collected for each row. Fiber data was analyzed to compare selection efficacy within the divergently selected subpopulations and between the marker and phenotypically selected populations. Divergent selections made on the basis of number of markers in the desired allelic state failed to show significant differences between subpopulations while those made on the basis of high and low value for the phenotypic trait were significant for both traits in both populations. Analyzing individual markers, none were found to be significant (p < 0.05) for either trait in both populations for both years. In Population 1 for UHML, two markers were found to be significant only in 2016, CIR196v197 (p=0.0416) and NAU1369v247 (p=.0011), and for FBS in 2016 only CGR6329v232 was significant (p= 0.0278). In Population 2, marker BNL1604v98 was significant in both years for UHML (p=0.0270 and p=.0448 in 2016 and 2017 respectively), and in 2016 for FBS (p=0.0425). Despite significance, numerical differences between selections with or without the BNL1604v98 allele were small.
The Conservation of Composite Luggage Trunks: Case Studies from the Kings Mountain National Military Park
(2015-02-25) Vance, Amanda Kathryn Comminos; Smith, C. Wayne; Hamilton, Donny L.; Thoms, Alston V.; Woodcock, David
The primary reason for conserving artifacts, archaeological or historical, is the preservation of information contained in those artifacts for future study. This thesis presents information on how to treat large, dry, composite artifacts using silicone oil while avoiding the invasive, possibly damaging, disassembly of constituent parts. It explores treatments of conservation for large composite artifacts using three luggage trunks from the Kings Mountain National Park as case studies. Conservation of these trunks was part of a larger project completed at Texas A&M University’s Conservation Research Laboratory. A strategy used in the conservation of composite artifacts comprised of organic materials is use of polymers, specifically silicone oil. Silicone oil was used as the main treatment of the organic elements. Different catalyst methods were experimented with to treat different materials. In combination with the silicone oil, established treatments appropriate to the inorganic (metal) materials were used. This thesis also explored advantages and disadvantages of dismantling an artifact for treatment. Implementing either preservation, restoration or dismantling the conservation methodology for this study was to actively remove agents of deterioration and stabilize the artifacts to prevent future deterioration and to retain their integrity. This study found that although the use of different catalysts could be beneficial, results were mixed. Although known undesirable results were avoided, in certain instances the experimental catalyst produced different undesirable effects. More in depth study would be required to ascertain if these results are avoidable or reversible. When possible, dismantling of an artifact should be avoided. In some cases however, it is more important to conserve the whole object at the expense of a particular part. Lastly, the findings of this study support the use of established conservation treatments in conjunction with more experimental methods. Treatments that do not conflict with others or un-do the results of each other can effectively be used to more completely treat composite artifacts.
The Conservation of Seventeenth Century Archaeological Glass
(2010-10-12) Arcak, Cory; Smith, C. Wayne; Bouton, Cynthia; Carlson, David
The primary goal of the conservator is to stabilize and conserve artifacts with the best possible treatment available. Ideally, these treatments are noninvasive and reversible, and maintain the integrity of the object as a top priority. In this respect, it is the responsibility of the conservator to research other possible treatments when traditional methods prove to be insufficient to properly stabilize and conserve an object. Sometimes choosing to treat with a seemingly unorthodox method is the only chance for the objects survival. Though glass is considered one of the most stable archaeological materials, noninvasive, reversible treatments are not always possible given the level of deterioration glass objects undergo within the archaeological setting, specifically the underwater or waterlogged archaeological setting. This research is a consideration and investigation of the use of silicone polymers and silanes as consolidation materials for 17th-century glass recovered from aqueous environments. Working within the Conservation Research Laboratory and the Archaeological Preservation Research Laboratory at Texas A and M University, a newly developed polymer passivation technique utilizing materials acquired from the Dow Corning Corporation was applied to archaeological glass recovered from the 1686 shipwreck La Belle, excavated in Matagorda Bay off the coast of Texas by the Texas Historical Commission from 1996 to 1997. The successful application of a hydroxyl ended silicone polymer Q-1 3563, combined with a methyltrimethoxysilane intermediate crosslinker, Q-9 1315, at a 15% solution by weight and catalyzed with dibutyltin diacetate (DBTDA Fascat 4200) occurred in 1999. This project was the first large scale application of silicone polymers and silanes to 17th-century archaeological glass recovered from a marine site. Through this investigation we answered a number of questions regarding the use and application of the silicone technologies and confirmed that these materials are a viable resource for glass consolidation and conservation in terms of the suggested conservation guidelines of the IIC. The silicone technology was successfully applied to numerous types, forms, colors and degradation levels of glass. This included successful application to composite artifacts and the retreatment of objects unsuccessfully treated with a "traditional" method.
Conservation of waterlogged linoleum
(Texas A&M University, 2005-02-17) Coke, BobbyeJo Evon; Smith, C. Wayne; Hamilton, Donny L.; Rowe, Marvin W.
Linoleum has been around for over a hundred years. With its invention by Frederick Walton in the 1860’s a new means of durable floor covering was introduced to the world. This new invention was promoted as durable, hygienic, and easy to maintain. In agreement with the Lake Champlain Maritime Museum, a study was commissioned to seek the best means to conserve linoleum from a canal boat excavated in the summer of 2002 in Lake Champlain. The Sloop Island Canal Boat is part of an excavation project that is studying the ways of life on the lake. Conserving waterlogged linoleum is a new area of study in conservation, and there is very little information dealing with the topic. This study will provide a baseline for the conservation of linoleum.
Determining Salt Tolerance Among Sunflower Genotypes
(2012-02-14) Masor, Laura Lee; Hague, Steve; Smith, C. Wayne; Crosby, Kevin
Crop lands around the world are becoming more salt-affected due to natural processes and agricultural practices. Due to this increase of salinization, acquisition of saline tolerant germplasm for breeding purposes is becoming a priority. Although cultivated sunflower is classified as a moderately salt tolerant crop, highly tolerant germplasm may be of value. The goal of this study was to screen Helianthus spp. in order to determine the salt tolerance of different genotypes. To accomplish this goal, a novel method of rapid screening was developed. Screening for tolerance at initial growth stages was accomplished by germinating seeds in varying concentrations of NaCl solution in petri dishes. Radicle lengths were measured as an indicator of tolerance. This method identified genotypes that are more tolerant than others during germination. Greenhouse trials were also conducted to ascertain morphological measurements during vegetative stages. Two field locations were chosen to screen germplasm for tolerance through physiological maturity; College Station, TX with low salt concentrations and Pecos, TX with high concentrations of salt in the soil and water. Vegetative growth measurements showed a significant genotype by environment interaction. Due to insect infestation in both locations, yields could not be accurately measured and thus compared between sites in 2010. Yields between locations in 2011 showed significant differences and identified germplasm more suited for cropping in salt affected soil. Seed oil content was determined with Fourier Transform Near-Infrared Spectroscopy. Seed oil content was not significantly different between locations, but was highly significant between genotypes. These screenings identified genotypes that are more salt tolerant than others.
Development and Characterization of Gossypium hirsutum L. x G. mustelinum Miers ex Watts Chromosome Segment Substitution Line Population
(2019-08-21) Hitzelberger, John Christian; Stelly, David; Dever, Jane; Smith, C. Wayne
Genetic improvements of Upland cotton (Gossypium hirsutum L.) must be continuous if the crop is to remain biologically and economically viable. The notoriously low genetic diversity found among Upland cottons constrains opportunities for improvements by breeding based on conventional elite-by-elite crosses. Fortunately, each related wild AD-genome species harbors about 80,000 genes and so introgression of a wild species genome could significantly increase the breadth of variation available among Upland cottons. Most genes from a non-domesticated donor species would expectedly be agriculturally neutral or deleterious, thus, for multi-genic traits, it would expectedly be virtually impossible to discern the presence of a beneficial allele or gene in a donor genome until that DNA variant is selectively integrated into an Upland cotton genetic background. In this study, sub-chromosomal segments of the G. mustelinum genome were concomitantly introgressed and separated by developing chromosome segment substitution lines (CSSLs). Modified backcross-inbreeding and marker-based selections enabled the creation of a panel of CSSLs, each containing one to several small sub-chromosomal introgressed alien segments but otherwise isogenic to the G. hirsutum recurrent inbred line parent and to each other. Genotyping was based on single-nucleotide polymorphism markers (SNPs). Segmenttargeted genotyping was based on PACE or KASP assays for small sets of two to several interspaced SNPs per segment, drawn from a recently developed genome-spanning panel of ~260 such assays. In contrast, genome-wide high-density genotyping was based on the Illumina Cotton63KSNP array for 15,000+ SNPs. Coverage and pedigree-based tracking of specific segments at BC4 and BC5 generations was enabled by prior CottonSNP63K-based genotyping of 18 BC2F1s. In 2017, 410 BC4F1s were backcrossed to G. hirsutum and selected, of which 92 were genotyped. In 2018, 378 of 933 BC5F1s were genotyped, self-pollinated and selected. Based on targeted analyses with spaced SNPs completed before January 2018, the CSSL panel comprises 65 BC5F1 plants that collectively contain approximately 50% of the G. mustelinum genome in a heterozygous state; these descend from 18 different BC2F1s. In subsequent research, each heterozygous donor segment must be recovered in homozygous form, and additional CSSLs with complementary genome coverage (~50%) must be identified to attain 100% of donor genome coverage. Available germplasm resources include BC5S1 seed from 378 BC5F1 plants and 77 BC4:5F1 families. To facilitate the follow-through efforts, I created well-organized computer spreadsheets that integrate relevant pedigree and SNP data; these help identify which segments to target, which pedigree to use for a given segment, and which SNPs to genotype for selection of heterozygotes and homozygotes. Recovery of homozygotes and complementary segments will be facilitated by the availability of plants and/or seed at BC5S1, BC5F1, and BC4F1 generations. To begin gauging if donor genes affect fiber quality traits, BC5F1 fiber samples were harvested on a single-plant basis within BC2-derived families and characterized using High Volume Instrument (HVI) analysis. ANOVA of HVI data showed that differences were significant among families (α=0.05) for micronaire (p = 0.0342), upper half mean length (p = 0.0004), elongation (p = 0.0253), and strength (p = 0.0224). If substantiated, the results would reflect dominant or co-dominant effects, but insufficient experimental replication precludes conclusiveness at this time. More authoritative deductions about dominant, co-dominant and recessive genotypic effects will be possible once homozygous BC5Sn CSSL lines are established, as these will be amenable to seed increases, use of larger experimental units, replication and multiple environments.
Development of a Cottonseed Dehulling Process to Yield Intact Seed Meats
(2013-04-22) Nunneley, Jacob Lawrence; Faulkner, William Brock; Parnell, Calvin B.; Lacey, Ronald E.; Smith, C. Wayne
With recent genetic advances in development of gossypol-free cotton varieties, there is interest in retrieving undamaged, dehulled cottonseed kernels for development of new food and feed products. Current methods used to dehull cottonseed provide a low turnout of undamaged kernels that would be desirable for new market niches where intact kernels are desirable. The first objective of the described work was to develop a process for dehulling fuzzy cottonseed to render a high percentage of undamaged seed meats. A series of methods were tested and optimized to identify the suite of processes that provided the highest yields. The final process included steam conditioning, cracking and dehulling using roller mills, and finally separating kernels from hull material using a roller separator and air aspirator. The reintroduction of un-dehulled seed to the roller mills for a second pass significantly increased the final yield of undamaged seed meats. Lab-scale tests show that yields of 65% to 70% can be obtained using this process, representing a significant increase over conventional dehulling, which typically results in less than 5% yields of undamaged kernels. The second objective of the research was to integrate components of the lab-scale milling process into a continuous-flow, pilot-scale system. The performance of the milling system with and without steam conditioning was evaluated. Pilot-scale, continuous-flow tests resulted in undamaged kernel yields of 67.9 ± 3.0% (mean ± 95% confidence interval) during wet milling, comparable to results of initial batch processing and far exceeding yields of whole kernels from current milling techniques. During dry milling, the efficiency of the system to extract all possible kernel material was found to be 68 ± 2.9%, but most of the resulting kernel material is in broken fragments between 3.35 mm and 0.706 mm in diameter.
Development of a screening method for drought tolerance in cotton seedlings
(Texas A&M University, 2007-04-25) Longenberger, Polly Suzanne; Smith, C. Wayne; Thaxton, Peggy; Binzel, Marla; McMichael, Bobbie
The key to an efficient screening method is the ability to screen large amounts of plant material in the shortest time possible. Unfortunately, due to the complexity of drought tolerance, a quick and effective screen for this trait has yet to be established. The research reported herein was designed to evaluate a screening method for drought tolerance in cotton (Gossypium hirsutum L.) seedlings. Twenty-one converted race stocks (CRS) and two cultivars were evaluated for seedling drought tolerance on an individual plant basis. CRS are day-sensitive primitive lines derived from various wild race stocks that were converted to day neutrality for use in temperate region plant improvement programs (McCarty et al., 1993). Genotypes were evaluated October - November 2004 and February - March 2005 under greenhouse conditions at the Norman E. Borlaug Center for Southern Crop Improvement, College Station, TX. Seedlings were subjected to three sequential cycles of drought at 15 days after planting (DAP). Drought cycles consisted of withholding water until the moisture content of "indicator" cone-tainers, containing Deltapine 491 (DP 491), had an average volumetric water content of 0.07. Plants were then watered to field capacity and percent survival was recorded after 48 hours. Genotypes differed in their percent survival following three consecutive drought cycles. Drought cycles 2 and 3 did not contribute to the separation of genotypes. DP 491 was the most tolerant genotype evaluated. None of the CRS were more or less tolerant than Acala 1517-99. CRS M-9044-0165 was the most stable genotype across the two experiments.
Diallel analysis and heritability estimates of fiber traits for ELS, Gossypium hirsutum L., progeny.
(2010-01-16) Berger, Gregory L.; Hague, Steve; Smith, C. Wayne; Zhang, Hongbin; Hinze, Lori
With a demand for high-quality cotton fiber in international markets, improvement of fiber quality in U.S. grown commercial cultivars is necessary. Smith, Hague, Thaxton, and Jones developed a group of experimental lines in 2008 that produced extra-long staple fiber (>35.6 mm). This study determined general combining ability (GCA), and specific combining ability (SCA) of four experimental ELS lines and four commercial cultivars utilizing biplot and conventional diallel analysis, determined performance of F2 progeny, calculated broad-sense (H2) heritability estimates for F2 progeny, and verified the ability of selected parental combinations to produce variable segregating populations with variability of fiber traits. Initial crosses were made in 2007, with additional crosses being made in the field and in a greenhouse in 2008. F1 progeny and parents were grown in a replicated trial near College Station, TX, in 2007 and 2008. F2 progeny lines and parents were grown in replicated trials at two locations in 2008. Due to a significant GxY interaction for all F1 fiber traits, data were reported by years. Experimental ELS lines showed positive GCA effects for fiber length, strength, and length uniformity, while the majority of commercial lines showed negative effects. These findings suggest experimental ELS lines contain alleles for fiber length and strength not present in this particular set of commercial cultivars. Experimental ELS lines exhibited negative GCA effects for lint percent, which suggests further selection is needed for these lines to be commercially competitive. Performances of F2 lines suggest differences in fiber traits are predominantly due to additive gene action. Furthermore, data suggests alleles for fiber length and strength is present in the experimental ELS lines not present in the commercial cultivars. F2 progeny exhibited moderate heritability for all fiber traits. Sufficient variability exists within selected F2 progeny to select for phenotypes exhibiting improved fiber quality over commercial cultivar potential with similar agronomic qualities of commercial cultivars. The ELS lines are a useful source of germplasm for plant breeders looking to improve fiber qualities in their programs.
Diallel analysis of within-boll seed yield components and fiber properties in upland cotton (Gossypium hirsutum L.) and breeding potential for heat tolerance
(Texas A&M University, 2004-09-30) Ragsdale, Paul Irwin; Smith, C. Wayne; Cothren, J. Tom; Betran, Javier; Starr, James L.
A diallel analysis of eight upland cotton (Gossypium hirsutum L.) genotypes was conducted in the field over two years to determine the potential for improvement in within-boll seed yield components and fiber quality parameters. Four exotic germplasm lines from the converted race stock (CRS) collection and four commercial types representing Texas, mid-South, and Eastern production regions were crossed and evaluated in a diallel with parents but without reciprocals according to Griffing's Model I, Method 2. Significant variation for genotypic, general combining ability (GCA) effects, and specific combining ability (SCA) effects (P 0.05) were identified for all traits studied indicating potential for improvements through selection. Significant interactions of these parameters with years were also observed, suggesting that selection should be based on multiple years and or locations. In addition to effects on yield, individual seed number traits were found to respond to heat stress under controlled growth chamber conditions, suggesting their potential for use in screening genotypes for heat tolerance. These traits were not found to interact with temperature, which indicates that selection for improvements in these traits could be conducted in any environment. Improvements in seed yield components and, putatively, in heat tolerance could be achieved using CRS M-9044-0162. As expected, CRS accessions reduced fiber quality parameters in addition to other agronomic traits, suggesting that improvements for within-boll seed yield components and heat tolerance should be made utilizing a backcross approach. Also observed in this population was a superior hybrid for fiber length and fiber strength from the cross of TAM 94L-25 with PD 6186. This combination could lead to improved fiber length and strength potential in upland cotton.
Enfield rifles: the composite conservation of our american civil war heritage
(2009-05-15) Cox, Starr Nicole; Smith, C. Wayne; Crisman, Kevin; Rosenheim, James M.
The object of this thesis is to discuss an experimental composite conservation process and its significance for the future of artifact conservation. Composite artifacts are artifacts comprised of multiple materials such as wood, iron, and brass. The experiment was designed around five Civil War Enfield rifles from the wreck of the Civil War blockade runner Modern Greece. The main conservation difficulty for both metal and wood from a saltwater site is the presence of chlorides. If not removed, the chlorides will cause the metals to further corrode. If the chlorides are left within the wood, once the wood dries the chlorides will crystallize and burst remaining cellular structure. The second major problem for wood is the cellular structure itself. Degraded waterlogged wood loses most of its cellular structure while submerged and this must be reinforced prior to drying or partial to total collapse of the wood will occur. Composite artifacts pose one more serious problem, their composite nature. In most instances treatments for one material type are damaging to the other materials present. Disassembly of an artifact often has detrimental effects on the whole artifact whether through initial damage or the inability to reassemble the artifact after stabilization. In 1979, four Enfield rifles from Modern Greece were compositely conserved using either tetraethyl orthosilicate, sucrose, or isopropyl rosin. All three treatments focused on the conservation of the wood, resulting in the current poor condition of the iron elements. The research of this thesis uses the combined treatments of silicone oil (to treat the wood) and electrolytic reduction [ER] (to stabilize the metals), with minimal disassembly. It was discovered that prolonged exposure of the wood elements during ER had deleterious effects, post the silicone oil treatment. This prompted a re-evaluation of the research strategy. It was determined to do a re-treatment of the wood components of four of the rifles with silicone oil after the ER process. It was apparent during the ER process that iron components had loosened and could be removed allowing the wood to be extracted from the ER process earlier than the iron. Even though the experiment did not go as planned and the initial results were undesirable, valuable information was ascertained for treatment strategies and positive results are expected for the final four rifles. The retreatment of the wood with silicone oil should allow the wood to retain its shape, making reassembly possible.
Evaluation of chlorophyll fluorescence as a tool for the identification of drought tolerance in upland cotton
(2009-05-15) Longenberger, Polly Suzanne; Smith, C. Wayne; Duke, Sara E.; McMichael, Bobbie L.; Rooney, William L.
A novel bioassay for the evaluation of plant water status was developed by Burke (2007). The research reported herein was designed to evaluate this new protocol as a tool for use in cotton breeding programs for the identification of drought tolerant genotypes. Twenty genotypes were selected to represent diverse germplasm pools for a two-year field evaluation. Replicated tests were performed in Lubbock, TX and College Station, TX in 2005, 2006, and 2007. Dryland and irrigated treatments were administered in a split plot arrangement of a randomized complete block design. Fluorescence measurements were taken at mid-bloom and late bloom growth stages of growth. Source leaf tissue was harvested at predawn and subjected to high temperature incubation with fluorescence measurements subsequently taken hourly for five hours. Drought stressed plants had not mobilized their carbohydrate reserves from their source leaves overnight and thus maintained cell viability and therefore higher chlorophyll fluorescence values throughout the incubation with the opposite being true for nonstressed plants. Fiber lint yield and fiber properties were measured at the conclusion of the 2005 season in College Station and the 2006 season in College Station and Lubbock for comparison with the fluorescence data. Five genotypes, ‘Acala 1517-99’, ‘Deltapine 491’ (PVP no. 200100159), ‘Tamcot CAMD-E’, ‘Tamcot 22’ and TAM 89E-51, an unreleased breeding line, were selected based on field evaluation results in a preliminary study in 2005 to be included in a diallel analysis to determine the heritability of fluorescence measurements. Genotype x treatment effects complicated the classification of genotypic responses to drought. Few and inconsistent correlations were found among fluorescence values and lint yield or fiber properties. The diallel analysis did not identify general combining ability or specific combining ability effects for chlorophyll fluorescence measurements. Thus this procedure provides little potential in selecting plants for drought tolerance when plants are grown under field culture. Selection among Tamcot 22 and TAM 89E-51 plants for high and low genotypes according to fluorescence values did not yield progeny different from unselected Tamcot 22 and TAM 89E-51.
The Evaluation of High Tannin Cotton Lines for Resistance to Rhizoctonia solani and Pythium aphanidermatum
(2011-02-22) Kennett, Raymond Matthew; Smith, C. Wayne; Thaxton, Peggy; Starr, James
Cotton seedling disease complex is caused by a number of pathogens inducing similar symptoms and can lead to thin, uneven stands that grow slowly and yield poorly. Preliminary work indicated that a set of high tannin cotton lines developed and released in 1989 by Texas A&M AgriLife Research, (Smith et al., 1990a, Smith et al., 1990b, Schuster et al., 1990) may possess increased resistance to disease. This evidence, along with additional studies that show a clear role of tannin in disease resistance, suggest that these high tannin cotton lines may prove useful in breeding for increased resistance to cotton seedling disease complex. High tannin cotton lines were screened for their resistance to Rhizoctonia solani and Pythium aphanidermatum. While no high tannin germplasm line was more resistant to R. solani than the resistant control, Tamcot SP 21, the potential for significant gains from selection was demonstrated. Fifteen high tannin lines expressed resistance to P. aphanidermatum equal to the resistant control, Tamcot Sphinx (El-Zik and Thaxton, 1996). This resistance was not shown to be correlated with tannin content, though it is still unclear whether or not this lack of correlation is real or due to limitations in measuring tannin in infected seedlings.
Evaluation of the genetic gain in upland cotton during the twentieth century
(Texas A&M University, 2007-04-25) Schwartz, Brian Matthew; Smith, C. Wayne; Speed, F. Michael; Thaxton, Peggy M.
Genetic gain studies in the past have been used to evaluate the historical improvement of different traits and give insight into what magnitudes of gain might be possible in the future. Additionally, they have been carried out to defend the role of genetics during periods of stagnant or decreasing yield trends. This study was conducted over a 2-year period (2003 and 2004) and included nine current or obsolete cotton (Gossypium hirsutum L.) cultivars grown in 5 plant densities designed to evaluate varying levels of interplant competition. Plant densities were single plant culture with plants spaced 3m x 3m, 2m x 2m, 1m x 1m, 1m x 0.3m, and two commercial populations with plants spaced 1m x 0.1m. Results were analyzed for each trait to determine whether genetic gains are interrelated with tolerance to interplant competition or strictly under genetic control. The rates of genetic gain for lint yield were highest in the 1m x 0.1m, 1m x 0.3m, and 1m x 1m treatment with slopes of 8.7, 8.2, and 7.1 kg ha-1 yr-1 respectively. The slopes were each significantly smaller in the 2m x 2m and 3m x 3m spaced populations with gains of 3.6 and 1.5 kg ha-1 yr-1 respectively, implying that for lint yield, genetic gains have been made for tolerance to interplant competition. Similarly, modern maize hybrids only out perform obsolete hybrids at higher plant densities. Genetic gain for lint yield, fiber length, fiber strength, and fiber micronaire made in the context of tolerance to interplant competition is due in large part to the excellent performance of Deltapine 491 (2002) at higher plant populations.
The evolution of decorative work on English men-of-war from the 16th to the 19th centuries
(Texas A&M University, 2005-08-29) Steere, Alisa Michele; Smith, C. Wayne; Rosenheim, James; Vieira de Castro, Luis Filipe
A mixture of shipbuilding, architecture, and art went into producing the wooden decorative work aboard ships of all nations from around the late 1500s until the advent of steam and the steel ship in the late 19th century. The leading humanists and artists in each country were called upon to draw up the iconographic plan for a ship??s ornamentation and to ensure that the work was done according to the ruler??s instructions. By looking through previous research, admiralty records, archaeological examples, and contemporary ship models, the progression of this maritime art form can be followed.

Browsing by Author "Smith, C. Wayne"

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