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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Estudios genómicos de desaturasas de ácidos grasos y evaluación de rendimiento en genotipos de trigo candeal con diferencias en su ciclo

Cuppari, Selva Yanet 17 March 2021 (has links)
El trigo candeal o trigo duro (Triticum turgidum L. ssp. durum) es una especie de trigo tetraploide (2n= 4x= 28 AABB) que se utiliza, principalmente, para la elaboración de pastas secas de calidad. El mejoramiento de esta especie está focalizado en la obtención de variedades de alta productividad con endosperma duro, vítreo, alto contenido proteico y pigmentos amarillos. Las variedades disponibles en Argentina son de hábito primaveral de ciclo corto a intermedio, y la siembra se realiza en el periodo comprendido entre junio y agosto. La principal zona de cultivo en nuestro país, es el sur de la provincia de Buenos Aires donde la ocurrencia de heladas entre abril y noviembre afecta al cultivo en estadio vegetativo y reproductivo. Los genes de desaturasas que introducen dobles enlaces en los ácidos grasos de cadena larga, se encuentran involucrados en la tolerancia a estrés por bajas temperaturas. La disponibilidad de secuencias de ADN, ARN y proteínas de desaturasas de gramíneas en las bases de datos públicas, permitió realizar un análisis in silico de las mismas, logrando caracterizar estructural y funcionalmente esta familia de proteínas. Se observó una distribución cromosómica dispersa y se predijo la localización subcelular más probable. Teniendo en cuenta que no existen secuencias de desaturasas caracterizadas de trigo candeal disponibles en GenBank (https://www.ncbi.nlm.nih.gov/), se realizó un análisis de la variabilidad genética en cinco genotipos, con diferencias en su grado de tolerancia a bajas temperaturas. Se detectó un bajo número de polimorfismos en la estearoil-ACP desaturasa (SAD) y ω- 3 lípido desaturasa (FAD3), mientras que ω- 6 lípido desaturasa (FAD2) mostró una mayor variabilidad. No se encontraron relaciones entre los polimorfismos en secuencia y el comportamiento frente a frío. El mapeo in silico de FAD2 permitió detectar la presencia de cuatro copias del gen localizadas en el cromosoma 6, incluyendo pseudogenes y un elemento transponible (TE, transponible element) insertado en la cuarta copia del genoma B. Las proteínas deducidas de las secuencias de trigo candeal fueron incluidas en el análisis in silico de gramíneas antes mencionado. Las regiones promotoras de los genes de desaturasas contienen sitios de unión a factores de transcripción de respuesta a estrés abiótico. Por otra parte, se realizó un estudio de respuesta a bajas temperaturas, en tres genotipos de trigo candeal, dos primaverales (BUCK AMBAR y CBW 0101) y uno invernal (MVTD 10- 98). Experimentos previos habían mostrado tolerancia a temperaturas bajo cero en cámara, de los genotipos MVTD 10-98 y CBW 0101 en estado vegetativo. El presente estudio incluyó el análisis de expresión del gen FAD2, la obtención del perfil de ácidos grasos y ensayos de conductividad eléctrica. Los ácidos grasos insaturados oleico (18:1), linoleico (18:2) y linolénico (18:3) fueron los que presentaron mayor nivel de cambios frente a bajas temperaturas. Se observó que las líneas CBW 0101 y MVTD 10-98, presentaron similares incrementos de 18:1 y 18:2 ante el tratamiento con frío y perfiles de expresión de FAD2 concordantes con los niveles de su producto 18:2. Las evaluaciones de integridad de membrana también estuvieron de acuerdo con las diferencias fenotípicas en la tolerancia. Además, se realizaron ensayos de rendimiento a campo en tres fechas de siembra (mayojunio- julio), durante dos años consecutivos en la Estación Experimental Agropecuaria Integrada Barrow - INTA (EEAI). Las variables evaluadas fueron: duración del ciclo a antesis, periodo de llenado de granos, rendimiento y medidas relacionadas (peso de granos, número de granos y sus subcomponentes, biomasa en antesis y madurez fisiológica, índice de cosecha y altura de planta), contenido de proteína en grano y peso hectolítrico. Se encontraron diferencias significativas entre años, fechas y genotipos en todas las variables. El primer año presentó un rendimiento promedio menor que el segundo (57 %), atribuido principalmente a las diferentes condiciones ambientales en relación a precipitaciones, suelo y temperaturas, mientras que el contenido de proteína en grano fue menor en el segundo año (22,25 %). En cuanto al momento de siembra, el rendimiento promedio fue mayor en fechas más tempranas en ambos años. La determinación de los periodos desde emergencia a antesis y de llenado de granos, combinados con diferentes fechas de siembra, permitieron explicar variaciones en el rendimiento. Además, los valores promedio de biomasa aérea total, peso de las espigas alcanzado en el periodo de llenado de granos (PEAT-MF) y peso promedio de granos por unidad de superficie (PG), fueron superiores en las fechas más tempranas. El peso de los granos por unidad de superficie, fue el principal componente numérico del rendimiento. Del análisis de componentes principales entre rendimiento y las variables asociadas, se deduce que el índice de cosecha, PG y PEAT-MF fueron las variables que mejor explicaron cambios en el rendimiento en todos los ensayos. Se evaluó, además, el daño por heladas en etapa de floración en el año 2016. Se identificaron tres formas de daño en espiga (deformada, por zonas y blanca) y el porcentaje promedio total varió entre genotipos desde 0,25 a 9,47 %. En general, los materiales menos afectados por heladas, fueron los de ciclo más largo, aunque también se observaron algunas diferencias en el nivel de daño entre genotipos de fenología similar. Este estudio aporta información de Triticum turgidum L. ssp. durum relacionada con su genoma, respuesta a estrés abiótico y efecto de fecha de siembra en el sudoeste de Buenos Aires. / Durum wheat, also called pasta wheat, (Triticum turgidum L. ssp. durum) is a tetraploid species of wheat (2n= 4x= 28 AABB), mainly produced for the elaboration of high quality dry pasta. Breeding of this species is focused on the obtention of high yield varieties, with hard and glassy endosperm, high protein contents, and yellow pigmentation. Available varieties in Argentina are spring-habit, short to intermediate cycle, with a sowing period that spans from June to August. The main cultivation area in our country is in the South of the Buenos Aires province, where frost occurrences (which may happen between April and November) negatively affect the crops during vegetative and reproductive stages. Fatty acid desaturase genes, which introduce double bonds in long-chain fatty acids, are related to low temperature stress tolerance. Availability of ADN, ARN, and desaturase sequences of grasses in public databases enabled in silico analyses, which in turn allowed to structurally and functionally characterize this protein family. A sparse chromosome distribution was observed, and a most likely sub-cellular location was predicted. Taking into account that there are no featured durum wheat desaturase sequences available in GenBank (https://www.ncbi.nlm.nih.gov/), a genetic variability analysis was performed in five different genotypes, each with different low temperature tolerance degrees. A low number of polymorphisms in the estearoil-ACP desaturase (SAD) and in the ω-3 desaturase (FAD3) where detected, while the ω-6 desaturase (FAD2) exhibited higher variability. No relationships between sequence polymorphisms and low temperature tolerance were detected. In silico mapping of FAD2 enabled to detect four copies of the gen, located in chromosome 6, including pseudogenes and a transponible element (TE) inserted in the fourth copy of the B genome. Proteins deduced from durum wheat sequences were included in the in silico gramineae analyses mentioned above. The promoting regions in the desaturase genes contain sites with bonding to transcription factors related to abiotic stress response. On the other hand, an analysis of low temperature response was performed on three genotypes of durum wheat, two spring-like (BUCK AMBAR and CBW 0101) and one wintry (MVTD 10-98). Previous experiments showed below-zero chamber temperature tolerance in genotypes MVTD 10-98 and CBW 0101 in vegetative state. The present study includes the expression analysis of the gene FAD2, the obtention of the fatty acid profile, and electric conductivity studies. The insaturated fatty acids oleic (18:1), linoleic (18:2), and linolenic (18:3), presented greater change levels under low temperatures. The lines CBW 0101 and MVTD 10-98, presented similar increments in 18:1 y 18:2 upon low temperature exposure, and FAD2 expression profiles in accordance with its product 18:2. Membrane 8 integrity evaluations were also in accordance with phenotypic differences in low temperature tolerance. In addition, field yield tests were performed in the Barrow Integrated Experimental Farming Station (Estación Experimental Agropecuaria Integrada, EEAI Barrow) of the National Agricultural Technology Institute (INTA), during three different sowing dates (May, June and July) along two consecutive years. The evaluated variables were: cycle length up to anthesis, grain filling period length, yield, and related mesures (grain weight, number of grains and their subcomponents, biomass during anthesis and physiological maturity, harvest index, and plant height), the protein contents in grain, and the hectolitre weight. Meaningful differences were found among years, sowing dates, and genotypes in all the evaluated variables. The first year presented an average yield 57 % lower than the second, which can be attributed to environmental conditions related to precipitation, soil, and temperatures, while the average protein contents in the grain was 22.25 % lower during the second year. Regarding the sowing date, average yield was higher in earlier dates in both years. Period determination from emergency to anthesis, and grain fill, combined with different sowing dates, are able to explain these yield differences. In addition, average total aerial biomass, spikes weight achieved during the grain filling period (PEAT-MF), and average grain weight per surface unit (PG), were all higher in earlier sowing dates. From Principal Component Analyisis between yield and the associate variables, it can be established that PG was the most important component of the yield, while PG and PEATMF were the variables that best explained yield changes in all the trials. In addition, the frost related damage during the flowering period was evaluated during 2016. Three different damage forms were identified (deformed, by zones, and white), where the average percentage varied between 0.25 and 9.47 %. In general, the genotypes less affected by frost were the ones of longest cycles, even though some differences were observed in the damage level among genotypes of similar phenology. This study provides information related to the genome and abiotic stress response of Triticum turgidum L. ssp. durum, and the effects of sowing date in the Southwest of Buenos Aires.
42

Survey of Durum Production Practices, 2007

Ottman, Michael 10 1900 (has links)
Durum growers were surveyed in cooperation with the USDA’s National Agricultural Statistics Service to determine production practices and their effects on yield and protein in the 2006 growing season. The survey was conducted in three regions: West (Yuma and La Paz counties), Central (Maricopa, Pinal, and Pima counties), and East (Cochise and Graham counties). Most of the durum in Arizona is grown in these three regions. We obtained responses from 83 out of an estimated 166 durum growers (50%) representing 46,331 out of 79,000 acres (59%). Durum was grown following cotton (41%), vegetables (27%), lettuce (16%), or other crops. The major varieties were Orita (30%), Kronos (25%), Ocotillo (16%), and Sky (11%). Herbicide was applied on 64% of the acreage. Flood irrigation systems accounted for 69% of the acreage, followed by furrow (17%). The crop was irrigated 6-7 times on average. The predominant soil texture was a sandy clay loam (36%), followed by sandy loam (35%) and clay loam (12%). The average planting date (germination irrigation applied) was December 21 in the Central region, January 4 in the West region and February 7 in the East region. The seed was planted at an average rate of 165 lbs/acre. Phosphorus was applied to only a third of the acreage, but when it was applied, the rate averaged 71 lbs P2O5/acre. Nitrogen rate averaged 224 lbs N/acre. Increased yield was associated with amendment application in the West region; certain varieties, amendment application, seeding rate between 120 and 159 lbs/acre, and nitrogen rate over 200 lbs N/acre in the Central region; and a seeding rate between 140 and 159 lbs/acre in the East region. Increased grain protein was associated with a previous crop of lettuce, lack of phosphorus application, and irrigation number in the West region; and a seeding rate of 140 to 159 lbs/acre and lack of phosphorus application in the East region. This survey documents associations, not cause-and-effect relationships, among durum production practices, yield, and protein.
43

Survey of Durum Production Practices, 2006

Ottman, Michael J. 10 1900 (has links)
Durum growers were surveyed in cooperation with the USDA’s National Agricultural Statistics Service to determine production practices and their effects on yield and protein in the 2006 growing season. The survey was conducted in two regions: West (Yuma and La Paz counties) and Central (Maricopa, Pinal, and Pima counties). These two regions represent about 95% of the durum acreage. We obtained responses from 85 out of an estimated 170 durum growers (50%) representing 40,580 out of 70,000 acres (58%). Durum was grown following vegetables (42%), cotton (41%), lettuce (12%), or other crops. The predominant soil texture was a sandy clay loam (47%), followed by sandy loam (30%) and clay loam (16%). Herbicide was applied on 52% of the acreage. The major varieties were Kronos (26%), Ocotillo (20%), Alamo (16%), and Orita (16%). Flood irrigation systems accounted for 87% of the acreage, followed by furrow (11%). The crop was typically irrigated 6 times. The average planting date (irrigation applied) was December 27 in the Central region and January 4 in the West region. The seed was planted at an average rate of 160 lbs/acre. Phosphorus was applied to only a quarter of the acreage, but when it was applied, the rate averaged 65 lbs P2O5/acre. Nitrogen rate averaged 224 lbs N/acre. Increased yield was associated with previous crops other than cotton in the West region, certain varieties, lack of herbicide application, planting in January in the West region and November or December in the Central region, a seeding rate between 100 and 160 lbs N per acre, and an N rate between 200 and 300 lbs N per acre. Increased grain protein was associated with a previous crop of vegetables or lettuce in the West region, lack of herbicide application in the Central region, manure application, clay loam or sandy clay loam soil, December planting in the West region, lack of phosphorus application, and fewer irrigations. This survey documents associations, not cause-and-effect relationships, among durum production practices, yield, and protein.
44

Survey of Durum Production Practices, 2004

Ottman, Michael J. 10 1900 (has links)
Durum growers were surveyed in cooperation with the USDA’s National Agricultural Statistics Service to determine production practices and their effects on yield and protein in the 2004 growing season. The survey was conducted in two regions: West (Yuma and La Paz counties) and Central (Maricopa, Pinal, and Pima counties). These two regions represent about 96% of the durum acreage. We obtained responses from 91 out of an estimated 195 durum growers (47%) representing about 38,000 out of 95,500 acres (40%). Durum was grown following cotton (48%), vegetables (43%), or other crops. The predominant soil texture was a sandy loam (36%), followed by clay loam (26%) and sandy clay loam (26%). Herbicide was applied on 67% of the acreage. The major varieties were Kronos (20%), WestBred 881 (18%), Kofa (14%), and Duraking (11%). Border flood irrigation accounted for 77% of the acreage, followed by furrow (11%), and level basin (10%). The crop was typically irrigated 6 to 7 times. The average planting date (irrigation applied) was December 19 in the Central region and January 7 in the West region. The seed was planted at an average rate of 163 lbs/acre. Phosphorus was applied to only a third of the acreage, but when it was applied, the rate averaged 67 lbs P2O5/acre. Nitrogen rate averaged 210 lbs N/acre. Grain yield tended to be higher following crops other than cotton grown on clay loam to sandy clay loam soils. Increased yield was associated with early planting, certain varieties, high N rate, and irrigation frequency. Higher protein content was associated with previous crops other than cotton, border irrigation, early planting, and N rate. This survey documents associations, not cause-and-effect relationships, among durum production practices, yield, and protein.
45

Survey of Durum Production Practices, 2005

Ottman, Michael J. 10 1900 (has links)
Durum growers were surveyed in cooperation with the USDA’s National Agricultural Statistics Service to determine production practices and their effects on yield and protein in the 2005 growing season. The survey was conducted in two regions: West (Yuma and La Paz counties) and Central (Maricopa, Pinal, and Pima counties). These two regions represent about 95% of the durum acreage. We obtained responses from 97 out of an estimated 195 durum growers (50%) representing 42,920 out of 75,400 acres (57%). Durum was grown following cotton (38%), lettuce (24%), vegetables (21%), or other crops. The predominant soil texture was a sandy loam (42%), followed by sandy clay loam (31%) and clay loam (21%). Herbicide was applied on 57% of the acreage. The major varieties were Kronos (21%), Alamo (16%), and Orita (16%). Level basin irrigation accounted for 52% of the acreage, followed by border flood (36%), and furrow (12%). The crop was typically irrigated 6 to 7 times. The average planting date (irrigation applied) was December 28 in the Central region and January 14 in the West region. The seed was planted at an average rate of 167 lbs/acre. Phosphorus was applied to only a third of the acreage, but when it was applied, the rate averaged 71 lbs P2O5/acre. Nitrogen rate averaged 213 lbs N/acre. Increased yield was associated with previous crops other than cotton, certain varieties, level basin irrigation, early planting in the Central region, a seeding rate between 140 and 160 lbs N per acre, N rate between 100 and 200 lbs N per acre, and an irrigation number of less than six in the West and seven in the Central Region. Grain protein was associated with varieties. This survey documents associations, not cause-and-effect relationships, among durum production practices, yield, and protein.
46

Growth and yield of durum and bread wheat

Zubaidi, Akhmad. January 1996 (has links) (PDF)
Bibliography: leaves 148-160. A series of experiments was conducted to examine the growth and nutrient uptake of durum and bread wheat at a number of sites in South Australia. The experiments examined response to water stress, the pattern of root and shoot growth, soil water extraction and nutrient uptake among a range of adapted bread wheat and durum wheat cultivars.
47

Estudo interpretativo da obra "Ensaio-90" para trio de percussão de Mário Ficarelli / Interpretative study from "Ensaio-90" for percussion trio by Mario Ficarelli

Arilho, Rodolfo Vilaggio, 1979- 26 August 2018 (has links)
Orientador: Fernando Augusto de Almeida Hashimoto / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Artes / Made available in DSpace on 2018-08-26T01:47:50Z (GMT). No. of bitstreams: 1 Arilho_RodolfoVilaggio_M.pdf: 22738314 bytes, checksum: 93559c1969c8f7eece56e6a0d6eb22d8 (MD5) Previous issue date: 2014 / Resumo: Este trabalho tem como objetivo a realização de um estudo interpretativo sobre a obra Ensaio-90 de Mário Ficarelli, composta para trio de percussão em 1990. Esse estudo não se prende somente na análise dos elementos composicionais da obra, mas sim utiliza a análise como ferramenta para discutir as possíveis decisões interpretativas, as escolhas do componente aleatório do material timbrístico como fator determinante do resultado final da obra, bem como a interação entre percussionistas quando em atuação em um grupo de percussão e sugestões para solução de possíveis problemas técnicos contidos na obra / Abstract: This work has a main goal to perform an interpretative study on the work Ensaio-90 by Mário Ficarelli, composed for three percussionists in 1990. This study is based not only in the analysis of the musical elements of the work, but rather utilizes the musical analysis as a tool to discuss the possible interpretative decisions, the, the choices on the random component of the timbre as an important factor for the final output of the work, as well the interaction among the acting percussionists playing as a group, and the suggestions to solve the technical issues through the work / Mestrado / Praticas Interpretativas / Mestre em Música
48

Genetics and agronomy of transient salinity in Triticum durum and T. aestivum.

Cooper, David Seth January 2005 (has links)
Title page, table of contents and abstract only. The complete thesis in print form is available from the University of Adelaide Library. / Transient salinity in soils is characterised by high concentrations of salts in the subsoil. Durum wheat (Triticum turgidum L. Var. durum) is less tolerant of transient salinity than locally developed bread wheat (Triticum aestivum) varieties, and this results in reliable durum production being restricted to relatively unaffected soils. Field trials were conducted to assess the relative impact of transient salinity, boron toxicity and bicarbonate on crop production and highlighted the importance of combining tolerance to all three subsoil constraints into varieties intended for widespread adoption; and if the area of durum production is to be expanded. The Na exclusion locus from the landrace Na49 was found to improve the adaptation of durum to sites affected by transient salinity and is now being intogressed into a wide range of breeding material. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1152134 / Thesis (Ph.D.) -- University of Adelaide, School of Agriculture and Wine, 2005
49

Russian Wheat Aphid Survey in Southeastern Arizona, 1990

Clark, Lee J. 09 1900 (has links)
Fifteen small grain fields, including eight wheat fields, two barley fields and five oat fields, throughout the grain growing areas of Graham, Greenlee and Cochise counties were surveyed weekly from the third week in March through the second week in June, to document the presence of Russian wheat aphid (RWA), other aphid, parasites and predators. RWA were found in all three counties and in all three grains. Presence of RWA caused chemical pest control applications in approximately 19%, 33% and 90% of the small grain fields in Graham, Greenlee and Cochise counties, respectively. Thirty three percent of the fields had beneficial parasites and predators were found 93% of the fields. Presence of parasites reduced the RWA populations in 80% of the cases and presence of predators had a dramatic effect on other aphids and was felt to be beneficial in controlling RWA.
50

Planting Date Effects on Small Grain Varieties at Maricopa under One-Irrigation Conditions

Ottman, M. J., Sheedy, M. D., Ramage, R. T. 09 1900 (has links)
Planting date is an important consideration when growing small grain varieties under reduced water use conditions. The objective of this study is to document interactions of planting date and varieties grown with a single irrigation near planting. Field studies were conducted at the Maricopa Agricultural Center during the 1988, 1989, and 1990 growing seasons. Six barley, durum, and wheat varieties were compared at four planting dates from November to February. Early November or early December planting dates were optimum. The relative performance of the varieties differed depending on the year and planting date. The highest yielding varieties over most planting dates were Solum and 6-39-1-1 (barleys), Mexicali (durum), and B85-277A and M83-39-18 (wheats). Improvement of barley, durum, and wheat genotypes for reduced water use conditions continues at the University of Arizona, and notable progress in durum and wheat performance has been achieved recently.

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