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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.
1

Synergism and Antagonism of Proximate Mechanisms Enable and Constrain the Response to Simultaneous Selection on Body Size and Development Time: An Empirical Test Using Experimental Evolution

Davidowitz, Goggy, Roff, Derek, Nijhout, H. Frederik 11 1900 (has links)
Natural selection acts on multiple traits simultaneously. How mechanisms underlying such traits enable or constrain their response to simultaneous selection is poorly understood. We show how antagonism and synergism among three traits at the developmental level enable or constrain evolutionary change in response to simultaneous selection on two focal traits at the phenotypic level. After 10 generations of 25% simultaneous directional selection on all four combinations of body size and development time in Manduca sexta (Sphingidae), the changes in the three developmental traits predict 93% of the response of development time and 100% of the response of body size. When the two focal traits were under synergistic selection, the response to simultaneous selection was enabled by juvenile hormone and ecdysteroids and constrained by growth rate. When the two focal traits were under antagonistic selection, the response to selection was due primarily to change in growth rate and constrained by the two hormonal traits. The approach used here reduces the complexity of the developmental and endocrine mechanisms to three proxy traits. This generates explicit predictions for the evolutionary response to selection that are based on biologically informed mechanisms. This approach has broad applicability to a diverse range of taxa, including algae, plants, amphibians, mammals, and insects.
2

Interação de genótipos com ambientes para qualidade de grãos carioca e caracteres agronômicos em feijoeiro-comum / Interaction genotype environment for carioca grain quality and agronomic traits in common bean genotypes

Silva, Fernanda de Cássia 07 October 2015 (has links)
Submitted by Onia Arantes Albuquerque (onia.ufg@gmail.com) on 2018-11-28T10:58:41Z No. of bitstreams: 2 Tese - Fernanda de Cássia Silva - 2015.pdf: 5826945 bytes, checksum: fd6401b916da6182fb0e4450ddb2faa3 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-11-28T13:35:50Z (GMT) No. of bitstreams: 2 Tese - Fernanda de Cássia Silva - 2015.pdf: 5826945 bytes, checksum: fd6401b916da6182fb0e4450ddb2faa3 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-11-28T13:35:50Z (GMT). No. of bitstreams: 2 Tese - Fernanda de Cássia Silva - 2015.pdf: 5826945 bytes, checksum: fd6401b916da6182fb0e4450ddb2faa3 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2015-10-07 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In the common bean crop, environmental influence and the differential behavior of genotypes to environments they have been reported for various important traits, and not restricted to grain yield. Initially, the producers crave for cultivars with high grain yield, early, maturing, upright plant architecture that is conducive to direct mechanized harvesting, commercial grain size and disease resistant. Unlike, the other segments of the production chain crave for grains with other attributes. For industry it is important that new cultivars present grains with high technology quality and processing and for consumers higher nutritional, cuisine and functional quality. Thus, these characteristics need to be combined to meeting the demands of the entire chain and enable the adoption of a new cultivar. And for this, the factors that influence the phenotypic expression of these traits require more studies. The objetive of this study were i) to study the effect of the genotype x environment interaction (GxE) in the grain yield associated with agronomic and grain quality traits and ii) identify carioca common bean genotypes that have simultaneously high adaptability and stability for these traits. Were conducted 79 trials Cultivation Value and Use (CVU) with carioca common bean lines, distributed in Distrito Federal and States of Goiás, Distrito Federal, Mato Grosso, Mato Grosso do Sul, Paraná, Santa Catarina, São Paulo, Pernambuco, Bahia, Alagoas and Sergipe. These experiments were conducted in the years 2011, 2012 and 2013, the sowing times of dry, winter and rainy. The experimental design was a randomized block design with three replications and plots of four lines, with 4 m row. The experiments consisted of 17 carioca common bean genotypes: thirteen elite lines and four controls (BRS Estilo, Pérola, BRS Sublime e CNFC 10762). The agronomic traits were evaluated: grain yield, plant architecture, lodging and reaction to anthracnose, angular leaf spot, common bacterial blight and wilt bacterial wilt, in addition to grain quality traits: visual aspect of grain, sieve in yield, 100 100 weight, cooking time and crude protein concentration. Individual and combined analyses of variance were realizedand analysis of adaptability and stability, the Nunes graphical method, for all characters. The index posts sum was used for the selection of genotypes favorable phenotypes for most traits, in addition to adaptability and joint stability. High environmental influence and interaction GxE in phenotypic expression for agronomic traits and traits related to grain quality was detected. It was possible to select genotypes with superiority for each character set. The use of the estimates of adaptability and stability combined with selection index was useful in evaluating genotype performance against the environmental variations. The lines CNFC 15033, CNFC 15070, CNFC 15025, CNFC 15049 and CNFC 15086 combined phenotypic good sized, high adaptability and stability for most agronomic traits. The genotypes who stand out for grain quality characters were CNFC 15097, CNFC 15038, CNFC 15025, CNFC 15033 and BRS Estilo. From these results, CNFC 15025, CNFC 15033, CNFC 15097 and CNFC 15038 line highlighted by to associate traits of agronomic interest the high quality of grain, as well as being stable and adapted to different cropping regions. Thus, these breeding lines have potential to be indicated as new cultivars and/or used as parents in breeding programs aimed at improving these phenotypes. / Na cultura do feijoeiro-comum, a influência ambiental e o comportamento diferencial dos genótipos aos ambientes têm sido relatados para vários caracteres de importância e que não se restringem à produtividade de grãos. A princípio, os produtores almejam cultivares com alta produtividade de grãos, precoces, arquitetura de planta ereta que propicie a colheita mecanizada direta, grãos com padrão comercial, além de serem resistentes às principais doenças. Diferentemente, os demais segmentos da cadeia produtiva anseiam por grãos com outros atributos. Para a indústria é importante que novas cultivares apresentem grãos com alta qualidade tecnológica e de beneficiamento. Para os consumidores, maior qualidade nutricional, culinária e funcional. Desse modo, essas características precisam ser combinadas para atender demandas de toda a cadeia e viabilizar a adoção de uma nova cultivar. E, para isso, os fatores que influenciam a manifestação fenotípica desses caracteres necessitam de mais estudos. Os objetivos deste trabalho foram: i) estudar o efeito da interação de genótipos com ambientes (GxA) para a produtividade de grãos associada aos caracteres agronômicos e de qualidade de grãos e ii) identificar genótipos de feijoeirocomum do grupo carioca que apresentem simultaneamente alta adaptabilidade e estabilidade para esses caracteres. Foram realizados 79 ensaios de Valor de Cultivo e Uso (VCU) com linhagens de feijoeiro-comum com grão carioca, distribuídos no Distrito Federal e nos Estados de Goiás, Mato Grosso, Mato Grosso do Sul, Paraná, Santa Catarina, São Paulo, Pernambuco, Bahia, Alagoas e Sergipe. Esses ensaios foram conduzidos nos anos de 2011, 2012 e 2013, nas épocas de semeadura da seca, inverno e águas. O delineamento experimental utilizado foi o de blocos ao acaso, com três repetições e parcelas de quatro linhas com quatro metros de comprimento. Os ensaios foram constituídos por 17 genótipos de feijoeiro-comum do tipo de grão carioca: treze linhagens elite e quatro testemunhas (BRS Estilo, Pérola, BRS Sublime e CNFC 10762). Foram avaliados os caracteres agronômicos: produtividade de grãos, arquitetura de planta, tolerância ao acamamento e reação à antracnose, manchaangular, crestamento bacteriano comum e murcha de curtobacterium, além dos caracteres de qualidade de grãos: aspecto visual dos grãos, rendimento de peneira, massa de 100 grãos, tempo de cocção e teor de proteína bruta. Realizaram-se as análises de variância individual e conjunta e, posteriormente, as análises de adaptabilidade e estabilidade, pelo método gráfico de Nunes, para todos os caracteres. O índice de soma de postos foi utilizado para a seleção dos genótipos com fenótipos favoráveis para os caracteres em conjunto, além da adaptabilidade e estabilidade conjunta. Foi detectada grande influência ambiental e interação de GxA na expressão fenotípica para os caracteres agronômicos e de qualidade dos grãos. Foi possível selecionar genótipos com superioridade para cada conjunto de caracteres. O emprego das estimativas de adaptabilidade e estabilidade aliada ao índice de seleção foi útil na avaliação do comportamento dos genótipos frente às variações ambientais. As linhagens CNFC 15033, CNFC 15070, CNFC 15025, CNFC 15049 e CNFC 15086 associaram boas médias fenotípicas, alta adaptabilidade e estabilidade para a maioria dos caracteres agronômicos. Os genótipos que se destacaram para os caracteres de qualidade de grãos foram CNFC 15097, CNFC 15038, CNFC 15025, CNFC 15033 e BRS Estilo. Com base nesses resultados, as linhagens CNFC 15025, CNFC 15033, CNFC 15097 e CNFC 15038 destacaram-se por associar características de interesse agronômico à boa qualidade dos grãos, além de serem adaptadas e estáveis às diferentes regiões de cultivo. Assim, essas linhagens elite tem potencial para serem indicadas como novas cultivares e/ou utilizadas como genitores em programas de melhoramento visando a melhoria desses fenótipos.

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