Thesis (Ph. D.)--University of Missouri-Columbia, 1996. / Typescript. Vita. Includes bibliographical references (leaves 84-87). Also available on the Internet.

Thesis (Ph.D.)--Memorial University of Newfoundland, 1999. / Restricted until June 2000. Bibliography: leaves 222-240.

Thesis (Ph.D.)--Ohio State University, 2005. / Title from first page of PDF file. Document formatted into pages; contains xxi, 195 p.; also includes graphics. Includes bibliographical references (p. 184-195). Available online via OhioLINK's ETD Center

Thesis (M.S.)--University of Missouri-Columbia, 2005. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (month day, year) Includes bibliographical references.

Universiẗat, Diss., 2004--Leipzig.

No description available.

A égua é classificada como poliéstrica estacional, o que implica suspensão da atividade reprodutiva cíclica usualmente a partir da metade do outono, na maioria destes animais. Esta resposta é devida à diminuição gradual no fotoperíodo natural, considerado como fator primário na sazonalidade reprodutiva. A ausência de ciclos ovulatórios durante os meses de inverno e a inconsistência da fase de ressurgência atingem não só os criadores de raças que procuram o nascimento de potros mais cedo na temporada reprodutiva oficial, mas principalmente aqueles que empregam a técnica da transferência de embriões. A obtenção de ovulações ao longo do ano possibilitaria a utilização reprodutiva ótima de éguas doadoras e receptoras. A fim de verificar a ciclicidade reprodutiva durante outono e inverno, dezessete éguas em uma propriedade do sul do Brasil foram distribuídas ao acaso em dois grupos. De quinze de Janeiro a doze de Setembro de 2009, os animais do grupo Tratamento foram submetidos a fotoperíodo diário fixo de 15 horas. Duas vezes por semana, o trato reprodutivo de todos os animais foi avaliado por ultrassonografia transretal, para verificação da presença de folículos dominantes e corpo lúteo. Dosagem de progesterona foi utilizada para confirmação de anestro. Oitenta e cinco por cento dos animais submetidos ao tratamento mantiveram ciclicidade reprodutiva, enquanto oitenta por cento dos animais controle entraram em anestro de inverno. Houve aumento na duração dos ciclos, devido a fatores endógenos, nutricionais e ambientais. Os resultados demonstram que o tratamento foi efetivo para obtenção de ciclos ovulatórios durante os meses de inverno. / The mare is classified as a seasonal poliestric, which means the suspension of reproductive activity usually from the first half of autumn, most of the mares. This is a response to the gradual decline in the natural photoperiod, considered as a primary factor of reproductive seasonality. The absence of ovulatory cycles during winter months and the inconsistency of the resurging phase strike both breeders who aim foals’ birth early in the official breeding season and those who employ the embryo transfer technique. Achieving ovulation throughout the year would enable the optimal reproductive use of donors and recipient mares. In order to check autumn and winter cyclicity, seventeen mares on a farm in southern Brazil were randomly assigned into two groups. From January 15th to September 12th 2009, animals in Treatment group were subjected to a fixed 15 hours daily photoperiod. Twice a week, the reproductive tract of all animals was examined by transrectal ultrasonography, searching for dominant follicles and presence of corpora lutea. Progesterone levels were used to confirm winter anestrus. 85% mares undergoing treatment maintained reproductive activity, while 80% of Control mares showed winter anestrus. There were changes in lenght of cycles, due to endogenous, nutritional and environmental factors. Results demonstrate that the treatment was effective to attain ovulatory cycles during winter months.

A égua é classificada como poliéstrica estacional, o que implica suspensão da atividade reprodutiva cíclica usualmente a partir da metade do outono, na maioria destes animais. Esta resposta é devida à diminuição gradual no fotoperíodo natural, considerado como fator primário na sazonalidade reprodutiva. A ausência de ciclos ovulatórios durante os meses de inverno e a inconsistência da fase de ressurgência atingem não só os criadores de raças que procuram o nascimento de potros mais cedo na temporada reprodutiva oficial, mas principalmente aqueles que empregam a técnica da transferência de embriões. A obtenção de ovulações ao longo do ano possibilitaria a utilização reprodutiva ótima de éguas doadoras e receptoras. A fim de verificar a ciclicidade reprodutiva durante outono e inverno, dezessete éguas em uma propriedade do sul do Brasil foram distribuídas ao acaso em dois grupos. De quinze de Janeiro a doze de Setembro de 2009, os animais do grupo Tratamento foram submetidos a fotoperíodo diário fixo de 15 horas. Duas vezes por semana, o trato reprodutivo de todos os animais foi avaliado por ultrassonografia transretal, para verificação da presença de folículos dominantes e corpo lúteo. Dosagem de progesterona foi utilizada para confirmação de anestro. Oitenta e cinco por cento dos animais submetidos ao tratamento mantiveram ciclicidade reprodutiva, enquanto oitenta por cento dos animais controle entraram em anestro de inverno. Houve aumento na duração dos ciclos, devido a fatores endógenos, nutricionais e ambientais. Os resultados demonstram que o tratamento foi efetivo para obtenção de ciclos ovulatórios durante os meses de inverno. / The mare is classified as a seasonal poliestric, which means the suspension of reproductive activity usually from the first half of autumn, most of the mares. This is a response to the gradual decline in the natural photoperiod, considered as a primary factor of reproductive seasonality. The absence of ovulatory cycles during winter months and the inconsistency of the resurging phase strike both breeders who aim foals’ birth early in the official breeding season and those who employ the embryo transfer technique. Achieving ovulation throughout the year would enable the optimal reproductive use of donors and recipient mares. In order to check autumn and winter cyclicity, seventeen mares on a farm in southern Brazil were randomly assigned into two groups. From January 15th to September 12th 2009, animals in Treatment group were subjected to a fixed 15 hours daily photoperiod. Twice a week, the reproductive tract of all animals was examined by transrectal ultrasonography, searching for dominant follicles and presence of corpora lutea. Progesterone levels were used to confirm winter anestrus. 85% mares undergoing treatment maintained reproductive activity, while 80% of Control mares showed winter anestrus. There were changes in lenght of cycles, due to endogenous, nutritional and environmental factors. Results demonstrate that the treatment was effective to attain ovulatory cycles during winter months.

Master of Science / Agronomy / Allan Fritz / Fusarium head blight (FHB) is a fungal disease, mostly commonly associated with F. graminearum, which affects cereal crops such as wheat resulting in substantial yield losses and reductions in grain quality. The onset of the disease can occur rapidly when warm, wet or humid weather coincides with flowering in the spring. The pathogen also produces mycotoxins such as deoxynivalenol (DON) that accumulate in the grain and can be toxic to humans and animals. This results in additional economic losses as contaminated grain must be discarded or blended to reduce the amount of toxin in order to meet federal regulatory limits. Development and deployment of resistant cultivars has proved to be an effective method to combat the disease, and many resistant sources have been reported in the literature with the majority of major resistance coming from Chinese landraces. Transferring resistance from these sources into cultivars adapted to the U.S. has been a slow process due to linkage of FHB resistance genes with poor agronomic traits. Therefore, it is important for breeders to search for sources of resistance in native material adapted to their local conditions. In this study, we aimed to identify quantitative trait loci (QTL) for resistance to spread of FHB within the head (Type II resistance), accumulation of DON toxin in grain (Type III resistance), and resistance to kernel infection (Type IV resistance). Plant material consisted of 148 doubled haploid (DH) lines from a cross between the two moderately resistant hard red winter wheat (HRWW) cultivars Art and Everest. The study was conducted for two years using a point inoculation technique in a greenhouse in Manhattan, KS. Three QTL conferring resistance to FHB traits were detected on chromosomes 2D, 4B, and 4D. The QTL on chromosomes 4B and 4D overlapped with the major height genes Rht1 and Rht2, respectively. Plant height has shown previous associations with FHB, though the underlying cause of these associations is not well understood. The majority of results have reported increased susceptibility associated with shorter plant types; however, in this study, the haplotype analysis for the Rht-B1 and Rht-D1 loci showed an association between the dwarfing alleles and increased resistance to FHB. This suggests either pleiotropic effects of these loci or perhaps linkage with nearby genes for FHB resistance. Markers close to the peaks of the FHB resistance QTL have the potential for Kompetitive Allele Specific PCR (KASP) marker development and subsequent use in marker assisted selection (MAS) to help improve overall FHB resistance within breeding programs.

Master of Science / Department of Agronomy / Antonio R. Asebedo / Sensor technology has become more important in precision agriculture, by real time sensing for site specific management to monitor crops during the season especially nitrogen (N). In Kansas N available in the soils can vary year to year or over a course of a year. The objective of this study was to compare current available passive (PS) and active optical sensor technologies (AOS) performance in regards to sky conditions effects and derive the NDVI (normalized difference vegetation index) relationship to wheat yield, as well as evaluate KSU optical sensor-based N recommendations against KSU soil test N recommendation system and sUAS (small unmanned aircraft systems) based recommendation algorithms with the PS and AOS platforms. Each year (2015-2016 & 2016-2017) five field trails across Kansas were conducted during the winter wheat crop year in cooperation with county ag agents, farmers, and KSU Agronomy Experiment Fields. Treatments consisted of N response curve, 1st and 2nd generation KSU N recommendation algorithms, sUAS based recommendation algorithms, and KSU soil test based N recommendations applied in the spring using N rates ranging from 0 to 140 kg ha⁻¹. Results indicate the Holland Scientific Rapid Scan and MicaSense RedEdge NDVI data was strongly correlated and generated strong relationships with grain yield at 0.60 and 0.57 R² respectively. DJI X3 lacks an NIR band producing uncalibrated false NDVI and no relationship to grain yield at 0.03 R². Calibrated NDVI from both sensors are effective for assessing yield potential and could be utilized for developing N recommendation algorithms. However, sensor based treatments preformed equal to higher yields compared the KSU soil test recommendations, as well as reduced the amount of fertilizer applied compared to the soil test recommendation. The intensive management algorithm was the most effective in determining appropriate N recommendations across locations. This allows farmers to take advantage of potential N mineralization that can occur in the spring. Further research is needed considering on setting the NUE (nitrogen use efficiency) in KSU N rec. algorithms for effects of management practice, weather, and grain protein for continued refinement.