Yes / The coexistence of hermaphrodites and female-sterile individuals, or androdioecy, has been documented in only a handful of plants and animals. This study reports its existence in the plant species Cardamine amara (Brassicaceae), in which female-sterile individuals have shorter pistils than seed-producing hermaphrodites. Morphological analysis, in situ manual pollination, microsatellite genotyping and differential gene expression analysis using Arabidopsis microarrays were used to delimit variation between female-sterile individuals and hermaphrodites. Female sterility in C. amara appears to be caused by disrupted ovule development. It was associated with a 2.4- to 2.9-fold increase in clonal propagation. This made the pollen number of female-sterile genets more than double that of hermaphrodite genets, which fulfils a condition of co-existence predicted by simple androdioecy theories. When female-sterile individuals were observed in wild androdioecious populations, their ramet frequencies ranged from 5 to 54 %; however, their genet frequencies ranged from 11 to 29 %, which is consistent with the theoretically predicted upper limit of 50 %. The results suggest that a combination of sexual reproduction and increased asexual proliferation by female-sterile individuals probably explains the invasion and maintenance of female sterility in otherwise hermaphroditic populations. To our knowledge, this is the first report of the coexistence of female sterility and hermaphrodites in the Brassicaceae.

Zusammenfassung Ein fehlerhafter Proteinabbau führt in höheren Eukaryoten zu diversen Krankheiten wie z.B. neurodegenerativen Störungen und Krebs. Es ist daher bedeutend die Regulationsmechanismen des Proteinabbaus zu verstehen. Intrazelluläre Proteine werden spezifisch durch das Ubiquitin-Proteasome System abgebaut. Cullin-RING Ligasen, welche durch das ubiquitin-ähnliche Protein Nedd8 aktiviert werden, binden und markieren das Zielprotein mit Ubiquitin. Diese ubiquitinierten Proteine werden durch das 26S Proteasome abgebaut. Die zwei Deneddylasen DenA und COP9 Signalosome (CSN) entfernen Nedd8 von unterschiedlichen Substraten. Diese Arbeit zeigt im Modellorganismus Aspergillus nidulans, dass DenA aus einer Kernfraktion sowie einer dynamischen zytoplasmatischen Subpopulation besteht. Zudem wird (A) das Zusammenspiel zwischen DenA und CSN im Kern untersucht und (B) die bisher unbekannte Phosphatase DipA, welche an der Regulation des zytoplasmatischen DenA und an der Zelldifferenzierung beteiligt ist, charakterisiert. (A) Eine erhöhte DenA Konzentration kann teilweise das Fehlen eines aktiven CSN kompensieren, indem es der Akkumulation an neddylierten Proteinen und damit CSN assoziierten Entwicklungsstörungen entgegenwirkt. Beide pilzlichen Deneddylasen haben somit unterschiedliche aber auch überlappende Funktionen. Zusätzlich zeigt sich, dass die DenA Kernfraktion, welche mit dem CSN interagiert, in der pilzlichen Entwicklung durch fünf benachbarte CSN Untereinheiten destabilisiert wird. Da diese Untereinheiten eine funktionelle Oberfläche bilden ist anzunehmen, dass die Interaktion von DenA mit dieser Oberfläche wichtig für die Stabilitätskontrolle der DenA Kernsubpopulation ist. (B) Zytoplasmatisches DenA wird zusammen mit DipA transportiert und akkumuliert an den Septen. Fehlt DipA erhöht sich die DenA Stabilität. Somit spielt DipA eine wichtige Rolle in der zytoplasmatischen DenA Stabilitätskontrolle. Zusätzlich führt das Fehlen von DipA zu einer erhöhten Septenbildung und Defekten in der lichtabhängigen Zellentwicklung des Pilzes. DipA wird somit, neben der DenA Stabilitätskontrolle, für die Zelldifferenzierung benötigt. Die Stabilität der zwei DenA Subpopulationen wird zusätzlich durch Phosphorylierung reguliert. Während vegetativen Bedingungen wird DenA durch die Phosphorylierung von S243 und S245 stabilisiert, was für die Initiierung der nachfolgenden asexuellen Entwicklung wichtig ist. Anschließend wird DenA durch eine Änderung des Phosphorylierungsmusters destabilisiert und abgebaut. Zusammenfassend zeigt diese Studie Einblicke in komplexe Mechanismen des DenA Proteinabbaus, welche womöglich auch in höheren Eukaryoten relevant sind.

La capacité de persistance d’une population face à un changement environnemental stressant est une question complexe à l’interface entre l’écologie et l’évolution. Le processus par lequel une population échappe à l’extinction en s’adaptant aux nouvelles conditions environnementales stressantes est nommé sauvetage évolutif. Ce cas particulier de dynamique éco-évolutive est de plus en plus étudié autant théoriquement, qu’expérimentalement, entre autres dans le contexte des changements environnementaux d’origines anthropiques. Cependant, les études modélisant ce processus négligent les interactions entre génotypes et environnements impactant le potentiel évolutif des populations faisant aux changements environnementaux. Dans le cadre de cette thèse, j’ai développé des modèles intégrant ces interactions. Pour cela, j’ai modélisé le processus de sauvetage évolutif de populations à reproduction asexuée, face à des changements environnementaux abruptes, en utilisant le paysage adaptatif de Fisher (modèle géométrique de Fisher (1930)). Ce paysage nous a permis de modéliser ces interactions génotypes-environnement et leur impact sur la proportion de mutations pouvant sauver une population. A travers deux modèles, considérant soit le sauvetage d’une population par une mutation d’effet fort, soit par un grand nombre de mutations d’effets faibles, nous avons pu dégager des prédictions pour la probabilité de sauvetage évolutif en fonction des conditions environnementales et des caractéristiques de l’organisme étudié. Ces modèles peuvent être paramétrés sur des données d’évolution expérimentale et leurs prédictions comparées à des données de traitement antibiotiques visant des pathogènes asexués. Au-delà du sauvetage évolutif, les modèles développés nous ont également permis d’établir des outils permettant de modéliser d’autres dynamiques éco-évolutives, intégrant des interactions génotype-environnement et leurs effets sur la distribution d’effets des mutations. / The persistence ability of a population facing a stressing environmental change is a complex question at the connection between ecology and evolution. The process by which a population avoid extinction by adapting to the new stressing environmental conditions is termed evolutionary rescue. This particular case of eco-evolutionary dynamic is increasingly investigated both theoretically and experimentally, among other things in the context of the environmental changes from human activity. However, the studies modelling this process neglect the interactions between genotypes and environments impacting the evolutionary potential of the populations facing environmental changes. In the context of this thesis, I developed models integrating these interactions. To this end, I modelled the process of evolutionary rescue in asexual populations, facing abrupt environmental changes, using the adaptive landscape of Fisher (Fisher’s geometric model (1930)). This landscape allowed us to model the genotypes-environments interactions and their impact on the proportion of mutations able to save a population. Using two models, considering either the rescue of a population by a mutation of strong effect, either by a large number of mutation of small effect, we derived predictions for the probability of evolutionary rescue, which depends on the environmental conditions and the characteristics of the studied organism. These models can be parametrized on data from evolutionary experiments and their predictions compared to data of antibiotic treatments aiming on asexual pathogens. Beyond evolutionary rescue, the models developed in this thesis also gave tools to model other eco-evolutionary dynamics, integrating genotype-environment interactions and their effects on the distribution of mutations effects.

Apomixis, or asexual seed development, if introduced into crop species, has the potential to greatly improve global food production. Towards this goal, this study focused on uncovering the genetic mechanisms that control the parthenogenesis step within apomixis whereby fertilisation is avoided. In the model apomict, Hieracium praealtum (Asteraceae), parthenogenesis is controlled by the LOSS OF PARTHENOGENESIS (LOP) locus. Previous research showed that in addition to genomic copies of candidate genes at LOP, the genome has at least three other copies referred to as alternative alleles. The main goal of this study was to investigate four candidate genes, Genes B, X, H and Y, at LOP by generating segregation data of the alternative alleles. BAC clones containing alternative allele sequences were identified and Roche 454 pyrosequenced. These sequences were used to design alternative allele specific primers for genotyping two Hieracium praealtum polyhaploid populations (~ 300 plants). Four major conclusions were drawn from this study. First, the alternative alleles were in fact acting like alleles to the LOP alleles of Genes B, X and Y. Second, allelic sequence divergence (ASD) of the LOP alleles of Genes B and X relative to the alternative alleles, indicated a recent and separate evolutionary history. Third and, unexpectedly, recombination was detected at the LOP locus, in contrast to other apomixis loci reported in the literature. Furthermore, Gene B was found to be very closely associated with parthenogenesis in the polyhaploid population indicating that it may be essential to parthenogenesis and therefore requires further investigation. On the other hand, the absence of Genes X, Y and H, due to recombination, had no impact upon parthenogenesis. Fourth, the sequence data suggested that the LOP and alternative alleles originated from a shared common allele ancestor. It is hoped that these findings have made a significant contribution towards the future goal of introducing apomixis into crop species.

Thesis (Ph. D.)--University of Washington, 1996. / Vita. Includes bibliographical references (leaves [269]-287).

Orientador: Luiz de Souza Corrêa / Banca: Aparecida Conceição Boliani / Banca: Shizuo Seno / Banca: João Carlos de Oliveira / Banca: Aloísio Costa Sampaio / Resumo: A cultura do maracujazeiro-amarelo (Passiflora edulis f. flavicarpa Deg.) tem sofrido com várias doenças, o que tem comprometido severamente a produção, determinando a migração da cultura. Dentre as doenças, a morte prematura de plantas tem se destacado, causando prejuízos nas lavouras do Estado de São Paulo. Essa doença tem sido associada a fungos do solo, como Fusarium oxysporum f. passiflorae, Fusarium solani, Phytophthora sp. e também a bactéria, como Xanthomonas axonopodis f. passiflorae. As medidas de controle da morte prematura são preventivas, e, uma vez afetada pelos patógenos, a planta morrerá, pois não há controle curativo. A aplicação de defensivos químicos não tem sido eficiente na solução do problema da morte prematura de plantas. A enxertia do maracujazeiro-amarelo em portaenxerto resistente é uma técnica promissora para o controle desta doença. Esse trabalho teve como objetivo verificar o desempenho de plantas de maracujazeiro-amarelo (Passiflora edulis f. flavicarpa) enxertadas em três diferentes espécies de maracujazeiro, em dois sistemas de enxertia, em área com e sem histórico de morte prematura. Foram conduzidos três experimentos, sendo dois em viveiro e um no campo, no município de Adamantina, SP, na região da Nova Alta Paulista, no período de dezembro de 2005 a julho de 2007. Pelos resultados verificou-se que os dois métodos de enxertia utilizados foram bem sucedidos para as três espécies de maracujazeiros estudadas. A utilização de P. giberti e P. alata como portaenxerto para P. edulis Sims f. flavicarpa são medidas promissoras para o controle da morte prematura de plantas. Plantas enxertadas sobre P. giberti apresentaram menor vigor a partir dos 180 dias, menor porte vegetativo, frutos com menor diâmetro e peso e menor produtividade. / Abstract: The yellow passion fruit (Passiflora edulis Sims f. flavicarpa Deg.) has been suffering with many diseases, what have been severely compromising the crop yield, determining the migration of the culture. Amongst the diseases, the premature death of plants has detached, causing crop losses the State of São Paulo. This disease has been associated with soil fungi, as Fusarium oxysporum f. passiflorae, Fusarium solani, Phytophthora sp, and also bacteria, as Xanthomonas axonopodis f. passiflorae. Measures to control premature death of plants are preventive, and, once affected by pathogens, the plant will die because there is no curative control. The application of chemical defensives has not been effective to solve the plants premature deaths. The grafting of yellow passion fruit in resistant rootstock is a promising technique for this disease control. This work aimed to evaluate the performance of yellow passion fruit grafted on three rootstocks, in two systems of grafting, cultivated in sites with or without disease history. Three experiments were carried out, two in nursery and one in the field, in Adamantina, SP, from December 2005 to July 2006. It was concluded that the two methods of grafting utilized were successful for the three species of Passiflora. The use of P. giberti and P. alata as rootstocks for P. edulis f. flavicarpa are promising measures for the control of premature death of plants. Plants grafting on P. giberti presented lower vigor form the 180 days, lower vegetative growth, fruits with lower diameter and weight and lower yield. / Doutor

No description available.

It was monitored tolerance for the 4 varieties contrary to late blight of potato.

Submitted by Erika Demachki (erikademachki@gmail.com) on 2017-03-17T20:10:43Z No. of bitstreams: 2 Tese - Ricardo Neves Guimarães - 2017.pdf: 2522150 bytes, checksum: 0037f07faf0bc8b7b76b5d36d87f7823 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-03-20T13:50:39Z (GMT) No. of bitstreams: 2 Tese - Ricardo Neves Guimarães - 2017.pdf: 2522150 bytes, checksum: 0037f07faf0bc8b7b76b5d36d87f7823 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-03-20T13:50:39Z (GMT). No. of bitstreams: 2 Tese - Ricardo Neves Guimarães - 2017.pdf: 2522150 bytes, checksum: 0037f07faf0bc8b7b76b5d36d87f7823 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-01-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Cerrado fruit arouse the growing economic interest in different market niches. Among these the Caryocar brasiliense Camb. It stands out due to its economic and social importance. The growing demand pequi fruit for the gastronomic and agroindustrial use indicates the need for studies to produce seedlings for reforestation of degraded areas, reforestation and possible cash crops, meeting the growing demand for seafood pequizeiro. The objective of this study was the development of an initial protocol for the vegetative propagation of pequizeiro through cuttings. For this four experiments were conducted to evaluate different factors which influence the rooting of pequizeiro as leafiness levels, age of the plant, pruning, cutting types and substrates. Through the studies it was found that young plant cuttings have greater potential for cutting with respect to adult trees. The leaves are key to cutting pequi because stakes with six leaflets showed 22.5% while rooting cuttings without leaves not taken root. Regarding the type of stake herbaceous cuttings showed higher callus induction and formation of root primordia in relation to softwood cuttings. But several factors influence the rooting of pequizeiro, further studies should be performed to define a protocol for cutting the pequizeiro. Por Through this study it was found that the pequizeiro introduced himself as a native species of the Cerrado with potential for cutting. / As frutíferas do Cerrado despertam interesse econômico crescente em diferentes nichos de mercado. Entre essas o pequizeiro (Caryocar brasiliense Camb.) se destaca em decorrência de sua importância econômica e social. A demanda crescente dos frutos de pequi para o uso gastronômico e agroindustrial aponta a necessidade de estudos para produção de mudas para revegetação de áreas degradadas, reflorestamentos e possíveis cultivos comerciais, atendendo a crescente demanda pelos frutos do pequizeiro. Objetivou-se com este estudo o desenvolvimento de um protocolo inicial para propagação vegetativa do pequizeiro via estaquia. Para isto foram realizados quatro ensaios avaliando diferentes fatores que influenciam no enraizamento do pequizeiro, como níveis de enfolhamento, idade da planta, podas, tipos de estacas e substratos. Por meio dos estudos verificou-se que estacas de plantas jovens possuem maior potencial para estaquia em relação às árvores adulta. As folhas são fundamentais para estaquia do pequi, pois estacas com seis folíolos apresentaram 22,5% de enraizamento enquanto estacas sem folhas não enraizaram. Quanto ao tipo das estacas herbáceas proporcionaram maior calogênese e formação de primórdios radiculares em relação a estacas semilenhosas. Porém vários fatores influenciam no enraizamento do pequizeiro, novos estudos devem ser realizados para definição de um protocolo para estaquia do pequizeiro. Por meio deste estudo verificou-se que o pequizeiro apresentou-se como uma espécie nativa do Cerrado com potencial para estaquia.

Thanks to the progress in genetic methods in population ecology, many critical discoveries were recently made in the field of reproductive strategies of social insect. Among them is the description of mixed reproductive strategies, combining advantages of sexual reproduction with thelytokous parthenogenesis. The queens of such species produce sterile castes through classical sexual process from fertilized eggs, while future queens develop asexually from unfertilized eggs. This original breeding system was first described in several genera of ants, but it was found very recently, that it is not restricted to social Hymenoptera, since it has been identified also in the phylogenetically remote eusocial clade of termites. Switching between the sexual process and thelytokous parthenogenesis, now known as Asexual Queen Succession (AQS), which enables a continuity of genetically almost identical queen generations after the death of the founding primary queen, was first reported only in one genus of lower termites, i.e. Reticulitermes. Recently, our research group participated at the identification of AQS in four other species from two subfamilies in higher termites. One of these species is Silvestritermes minutus. This species is locally abundant in French Guiana and lives in small, well shaped nests on...