This thesis is focused on evaluation of the compatibility of entomopathogenic fungus Isaria fumosorosea with different species of entomopathogenic fungi and mycoparasitic fungi at different temperatures. The strains of species Beauveria bassiana, Metarhizium anisopliae, Lecanicillium muscarium, Coniothyrium minitans and Clonostachys rosea f. catenulata were selected for experiments base on compatibility. The results showed that combination of I. fumosorosea with species L. muscarium is compatible. The species do not limit to each other in the environment at all temperatures (15, 23 and 25 °C). On the other side, fungus I. fumosorosea in combination with other species have affected their growth and spore production. The efficacy of entomopathogenic fungi against larvae Tenebrio molitor was evaluated. The most effective species against larvae were species I. fumosorosea, B. bassiana and M. anisopliae. On the contrary, the smallest effective was observed after infection larvae by L. muscarium. Mycoparasitic fungus C. rosea f. catenulata was not able to directly infect larvae of T. molitor. This species did not infect healthy larvae. However it is able to infect weakened individuals or is growing as saprotrophs on the cadavers.

A Podridão Floral dos Citros é uma doença que tem limitado a produção citrícola em várias regiões produtoras do mundo. A sintomatologia esta associada principalmente quando coincide alta pluviosidade e intensa florada. O fungo se encontra na forma quiescente em órgãos vegetais e na presença de nutrientes exógenos reinicia o processo de infecção. Os objetivos do trabalho foram: (i) avaliar o efeito das águas de lavagem bruta (ALB) obtidas a partir de flores, botões e folhas de laranjeira Valência, sobre o crescimento micelial, germinação e formação de apressórios por C. acutatum; (ii) avaliar o efeito dos compostos voláteis liberados pelas ALB e as frações produzidas a partir das águas de lavagem de flores e botões sobre a germinação e formação de apressórios; (iii) estabelecer uma metodologia para observação de estruturas de infecção em folhas de citros. Foram realizados dois bioensaios de germinação e formação de apressórios e crescimento micelial para as águas de lavagem bruta. O primeiro representado pelos tratamentos: testemunha (T), água de lavagem das flores (F), botões (B), folhas novas (FN), folhas velhas (FV) e a diluição da água das flores em 1:10, 1:100, 1:1000 e 1:10000 (v/v). O segundo por testemunha (T), água de lavagem das flores (F), botões (B), folhas novas (FN), folhas velhas (FV) e a autoclavagem destes mesmos tratamentos. Os voláteis liberados pelas águas de lavagem de flores e botões primeiramente foram identificados por SPME-CG-MS e logo após as frações foram obtidas de acordo com o tempo de retenção de cada pico encontrado, totalizando 5 frações para cada amostra. Realizou-se um bioensaio de germinação e formação de apressórios com as frações obtidas em contato direto com os esporos. Para a observação de estruturas de infecção, discos foliares de plantas cítricas foram inoculados, submetido a clareamento e posterior coloração para a observação ao microscópio. Os resultados das ALB mostraram que todos os tratamentos estimularam a germinação e formação de apressórios por C. acutatum. Os voláteis não apresentaram efeito indutor sobre os esporos, porém quando fracionados e colocados em contato direto com as estruturas, as frações botão apresentaram uma maior atividade indutora quando comparada a testemunha. Nenhum tratamento alterou o crescimento micelial do fungo. A melhor visualização dos esporos nas folhas ocorreu 48 horas após a inoculação. Com base nesses resultados, pode-se concluir que as águas de lavagem estimulam a germinação e formação de apressórios, e apenas os voláteis presentes nas frações botão estimularam a germinação de C. acutatum. / The Post Bloom Fruit Drop is a limiting disease in citrus production around the world and the symptoms are associated to high rainfall and intense blooming. The fungus is found in a quiescent state in plant organs and under the presence of exogenous nutrients it restarts the infection process. Thus, the objectives of the work were: (i) evaluate the direct effect of washing crude water (WCW) obtained from flowers, flower buds and leaves of Valencia orange trees on the mycelial growth, germination and appressorium formation by C. acutatum; ii) evaluate the effect of volatile compounds released by the WCW and the fractions obtained from the washing water from flower and flower buds in the germination and appressorium formation, and (iii) establish a methodology for observing structures of fungal infection in citrus leaves. Two bioassays were carried out to evaluate germination, appressorium formation and mycelial growth in the presence of WCW. The first one was represented by the treatments: control (C), washing water from flowers (F), flowers buds (FB), young leaves (YL), old leaves (OL), and dilution (1:10, 1:100 , 1:1000 and 1:10000; v/v ) from the flower washing water. The second one included control (C), washing water from flowers (F), flowers buds (FB), young leaves (YL), old leaves (OL) and all of washings autoclaved. The volatiles released by the washing water from flowers and flowers buds were first separated and identified by SPME-GC-MS and then fractions were obtained according to the retention time of each peak found, making up five fractions for each sample. A bioassay for germination and appressorium formation was carried out by using the fractions obtained and placed into direct contact with the spores. To observe the fungal infection structures, leaf discs from citrus plants were inoculated, subject to bleaching and then stained for observation under a microscope. The results obtained by using the WCW samples showed that all treatments stimulated spore germination and appressorium formation by C. acutatum. The volatiles did not show any inductive effect on the spores, but when fractionated and placed into direct contact with the fungal structures, the fractions from the flowers buds showed a higher inducing activity when compared to the control. None treatment changed the in vitro mycelial growth of the fungus and the best visualization of spores in the leaves occurred 48 hours after inoculation. Based upon on these results, it can be concluded that the crude washing water stimulated germination and appressorium formation, and only the volatiles present in the fraction flowers buds were able to stimulate the germination of C. acutatum spores.

A ferrugem da videira, causada pelo fungo Phakopsora euvitis, é uma doença importante para a viticultura brasileira por causar desfolha precoce e, consequentemente, prejudicar a maturação dos frutos e comprometer as safras seguintes. Por ser um patógeno biotrófico, a preservação de urediniósporos para estudos com o patógeno, se faz em folhas do hospedeiro vivo. Em outras espécies de ferrugens é possível conservar os esporos em condições controladas por longos períodos de armazenamento. Outro ponto importante, para auxiliar na compreensão da epidemiologia do patossistema, está relacionado com as condições ambientais favoráveis na germinação de urediniósporos e na patogenicidade do fungo em folhas de videira. Com o objetivo de preservar o patógeno e determinar as condições ambientais favoráveis para a doença, foram avaliados: (1) O efeito da temperatura e desidratação na manutenção da viabilidade dos esporos; (2) O efeito da temperatura e do período de molhamento na germinação de urediniósporos e na patogenicidade em mudas de \"Niágara Rosada\" inoculadas. Os resultados obtidos mostraram que a desidratação dos esporos proporcionou maior viabilidade destes ao longo do tempo, para todas as condições de armazenamento testadas. A desidratação seguida pelo armazenamento a -80°C conseguiu manter os esporos viáveis, com uma alta porcentagem de germinação, por até 150 dias de armazenamento. Os urediniósporos armazenados no ambiente, independente do processo de desidratação, não conseguiram manter sua viabilidade por um período superior a 15 dias. A faixa de temperatura para germinação de urediniósporos foi ampla, entre 10 e 30°C, com um ótimo em 20°C. A expressão de sintomas em plantas inoculadas foi maior nas temperaturas de 25 e 30°C. O período de molhamento mínimo estimado pelo modelo monomolecular foi de 7 horas para as plantas mantidas a 15 °C e 5 horas para as plantas mantidas a 20, 25 e 30 °C. Para períodos acima de 6 horas de molhamento, a maior severidade da doença ocorreu na temperatura de 30 °C. Não ocorreu sintomas em plantas inoculadas e mantidas a 35°C em nenhum dos períodos de molhamento testados. O período de latência da ferrugem foi de 7 dias para plantas inoculadas e mantidas a 25 e 30°C, estendendo-se para 13 dias quando as plantas foram mantidas a 15°C. / Grapevine rust, caused by Phakopsora euvitis, is an important disease in brazilian viticulture, causing early defoliation and jeopardizing the maturation of fruits and the following crop season. P. euvitis is a biotrophic pathogen, and for research purpose, uredospores are kept through inoculation in grapevine plants. In other species of rust, it is possible to preserve spore under controlled conditions for long periods of storage. Understand the favorable environmental conditions for uredospores germination and the pathogenicity of the fungus on grapevine leaves are important for the understanding of the pathosystem epidemiology. In order to preserve the pathogen and determine the favorable conditions for the disease were evaluated: (1) The effect of temperature and dehydration in maintaining the viability of the spores; (2) The effect of temperature and wetness period on uredospores germination and pathogenicity in \'Niágara Rosada\' inoculated plants. The results showed that spore dehydration maintained high viability, for all the tested storage conditions. Dehydration followed by storage at -80°C kept viable spores, with a high percentage of germination, for 150 days of storage. The uredospores stored in the environment, independent of the dehydration process, could not maintain their viability for a period exceeding 15 days. The temperature range for uredospores germination varied from 10 to 30°C, with an optimal at 20°C. The expression of symptoms in inoculated plants was higher at 25°C and 30°C temperatures. The minimum wetness period estimated by the monomolecular model was 7 hours for plants kept at 15 °C and 5 hours for plants kept at 20, 25 and 30 ºC. For wetness periods up to 6 hours, the highest disease severity occurred at 30 °C. There were no symptoms on inoculated plants maintained at 35°C in any of the tested wetness periods. The rust latency period was 7 days for inoculated plants kept at 25 and 30°C extending for 13 days when the plants were kept at 15°C.

A genome is shaped by many different forces. Recombination can for instance both create and maintain genetic diversity, but the need to locally reduce recombination rates will also leave specific signatures. Genetic elements can act selfishly and spreading at the expense of the rest of the genome can leave marks of their activity, as can mechanisms that suppresses them, in a phenomenon known as genomic conflict. In this thesis, I have studied the forces driving genome evolution, using modern genome sequencing techniques and with a special focus on a class of selfish genetic elements known as Spore killers found in the fungus Neurospora. First, we show novel findings on large-scale suppression of recombination by non-structural means in the N. tetrasperma genomes. In contrary, in the genomic region harbouring the spore killer elements Sk-2 and Sk-3 of N. intermedia, a dense set of inversions that are interspersed with transposable elements have accumulated. The inversions are unique for each killer type, showing that they have a long separated evolutionary history and likely have established themselves independently. For the Sk-2 haplotype, where we have polymorphism data, we see signs of relaxed selection, which is consistent with the hypothesis that recombination suppression reduces the efficacy of selection in this region. These results show the strong effects the divergent selective forces of genomic conflicts can have on chromosome architecture. Furthermore, we investigate the hypothesis that spore killing can drive reproductive isolation, by comparing the fertility of crosses between N. metzenbergii and either killer or non-killer N. intermedia strains. We show that crosses with spore killer strains have lower fertility, which cannot be explained by the killing itself, but is potentially caused by an incompatibility gene captured in the non-recombining region. Finally, we identified the genetic element responsible for causing spore killing in the Sk-1 spore killer strains found in N. sitophila. Unlike the Sk-2 and Sk-3 elements, Sk-1 is not connected to a large, non-recombining region, but is caused by a single locus, and we also find indications that this locus was introgressed from N. hispaniola.

No description available.

No description available.

(Bahasa Indonesia) Analisa yang terperinci mengenai lingkungan di masa lalu, iklim dan sejarah penggunaaan lahan di wilayah Indonesia sangat penting untuk memperoleh pemahaman yang lebih baik mengenai hubungan manusia-lingkungan dan untuk mencegah ketidakpastian perkembangan wilayah tersebut di masa depan. Indonesia merupakan salah satu wilayah yang memiliki keanekaragaman terbesar, dan pada saat yang bersamaan juga merupakan salah satu Negara yang mempunyai jumlah penduduk terpadat di dunia. Seiring dengan sejarah, pengaruh dari aktivitas manusia pada suatu daerah menjadi semakin kuat. Penelitian ini dilakukan untuk mengakses peranan manusia terhadap perubahan lingkungan. Penelitian kami difokuskan pada rekonstruksi pola vegetasi di masa lampau, perubahan lingkungan dan interaksi antara manusia dan lingkungan yang tercermin dalam sedimen laut di perairan Indonesia. Dua macam pendekatan yang digunakan dalam studi ini adalah: polen (serbuik sari), yang berasal dari darat dan diharapkan bisa memberikan informasi yang beragam tentang vegetasi dan dinamika penggunaan lahan, dan organic dinoflagelata yang berasal dari lingkungan laut dan merefleksikan perubahan parameter air secara kuantitatif (misal. SST, SSS) dan kualitatif (mis: kondisi tropic dilihat dari segi makro-elemen utama dan oksigen terlarut dalam air). Selain itu, arang mikro dipelajari untuk mendapatkan data mengenai sejarah kebakaran di wilayah tersebut dan untuk memperoleh data tambahan untuk interpretasi polen dan data dinoflagelata. Penelitian dilakukan di dua situs sebagai perbandingan: pertama, di wilayah Jawa yang padat penduduk dengan sejarah panjang dari dampak aktivitas manusia yang menghasilkan lanskap pertanian yang luas, dan yang kedua, di wilayah Kalimantan Selatan dengan kepadatan penduduk yang tidak terlalu tinggi dan tidak banyak perubahan akibat pengaruh aktivitas manusia dan masih merupakan vegetasi alami. Metode yang digunakan, palinologi laut memerlukan perhatian khusus dalam interpretasi data. Faktor pengendapan polen adalah sangat penting, terutama untuk daerah-daerah dengan pengaruh kuat dari angin dan arus laut seperti wilayah Indonesia dimana sistem iklim secara keseluruhan didorong sebagian oleh pergantian musim. Untuk mendapatkan beberapa pemikiran mengenai transportasi sedimen di wilayah ini, kami mempelajari dan membahas secara rinci perbedaan jumlah polen yang dikumpulkan pada kondisi musim hujan yang berbeda serta selama waktu perpindahan musim. Subyek manuskrip pertama kami adalah kemelimpahan dan komposisi taksa modern polen dan spora yang didapat dari sedimen yang terakumulasi di Samudera India sebelah barat daya Jawa. Hasil yang diperoleh digunakan untuk interpretasi lebih lanjut dari fosil polen laut. Sejarah intensifikasi penggunaan lahan dan perubahan vegetasi lebih dari 3500 tahun yang lalu yang diperoleh dari dinoflagelata dan kumpullan polen dari sedimen laut dipresentasikan dalam jurnal yang kedua. Studi ini didasarkan pada perbandingan dua core laut dari lepas Laut Jawa dekat Kalimantan Barat (Sungai Jelai) and bagian timur laut Jawa (Sungai/Bengavan Solo). Pada manuskrip yang ketiga, hasil ini diperbandingkan dengan sedimen core dari lepas pantai yang diambil dari bagian hulu sungai Pembuang. Studi ini membahas mengenai hasil analisa geokimia dan analisa dinoflagelata dalam cakupan paleoekologi dan paleoenvironment. Manuskrip kelima membahas tentang keragaman polen dalam core sedimen laut dari wilayah Indonesia. Studi ini merangkum pengetahuan yang diperoleh selama meneliti core sedimen dari Laut Jawa dan dari studi perangkap sedimen di Samudera Hindia. Dalam bentuk atlas polen, kami memberikan hasil analisis secara rinci dari daftar taksa polen dan dilengkapi dengan foto mikro pada tingkat fokus yang berbeda. Hasil keseluruhan dari penelitian ini akan memberikan kontribusi pada pengetahuan tentang dinamika ekosistem dan sejarah alam di wilayah Indonesia dan dapat membantu investigasi paleoekologi dan paleo-iklim di masa depan secara lebih rinci.

How long has the extant flora been present in the Antarctic? Glaciological reconstructions propose that most areas in Antarctica were covered by thick ice sheets throughout the Last Glacial Maximum (LGM; ~22-18 kya) as well as previous glaciations, suggesting terrestrial life must have been extremely limited during these periods. In contrast, recent biogeographic and genetic studies support most extant groups of Antarctic terrestrial fauna having survived past glaciations in situ. However, studies on the origin and age of the Antarctic flora remain sparse. Applying population genetic, phylogeographic and divergence time analyses I assessed the global biogeography, origin and age of several abundant Antarctic moss species, including: four Polytrichaceae mosses, characterised by having bipolar distributions, the most common (~45% of species) distribution pattern amongst Antarctic mosses; the globally widespread moss Ceratodon purpureus; the bank-forming moss Chorisodontium aciphyllum, also known for its old sub-fossils in Antarctica and long-term viability from revival experiments; and, lastly, the genus Schistidium, the most species-rich moss genus in Antarctica, including many endemic species. Genetic analyses revealed evidence of long-term (multi-million year) survival of plants in Antarctica (several species of Schistidium, Ceratodon purpureus, and possibly Polytrichum juniperinum). However, evidence for a likely more recent (< 100 ky) arrival of Chorisodontium aciphyllum was also found. Some species revealed multiple separate dispersal events to the Antarctic, suggesting the region may be less isolated for spore-dispersed organisms than previously thought. Evidence for increased genetic diversity in the northern maritime Antarctic compared to other regions point at it including potential refugial areas. Furthermore, genetic patterns revealed geographic features that enable and limit the connectivity of bryophytes globally as well as in Antarctica. This study suggests that, despite the harsh polar climate during glaciation periods, many bryophytes have had a much longer presence in Antarctica than previously thought.

Chez les spores de bactéries, le photoproduit le plus abondant formé dans l'ADN irradié par les UV est un dimère de thymines appelé Photoproduit des spores (SP, 5-(a-thyminyl)-5,6-dihydrothymine). Au début de la germination, ce photoproduit est spécifiquement réparé par une enzyme, la Spore Photoproduct Lyase (SPL), régénérant les deux résidus thymine originaux. Cette enzyme est une protéine Fe-S qui appartient à la famille des « Radical-SAM ». Les protéines de cette famille d'enzymes possèdent un centre [4Fe-4S], coordiné par 3 cystéines conservées organisées selon le motif CxxxCxxC, et utilisent la SAdénosylméthionine comme cofacteur. Elles fonctionnent toutes selon un mécanisme <br />radicalaire, initié par la formation du radical 5'-désoxyadénosyle issu de la coupure homolytique de la S-Adénosylméthionine par le centre [4Fe-4S] réduit. Dans ce travail, nous avons effectué une caractérisation biochimique et spectroscopique des SPL de Clostridium acetobutylicum et Bacillus subtilis. Par ailleurs, nous avons synthétisé un substrat minimum sous la forme d'un dinucléoside monophosphate appelé SPTpT, pour lequel une caractérisation structurale par RMN a été réalisée. Le SPTpT est reconnu et efficacement réparé par l'enzyme, ce qui nous a permis d'obtenir de nouvelles informations sur le mécanisme enzymatique de réparation. Enfin, la séquence primaire des SPL contient une 4e cystéine conservée, essentielle à la réparation, mais qui n'est pas impliquée dans la coordination du centre [Fe-S]. Nous nous sommes intéressés au rôle de cette cystéine dans le mécanisme de réparation grâce à l'étude biochimique et enzymatique du mutant SPLC141A.

Tuber aestivum is an ectomycorrhizal ascomycete with underground fruit bodies. It is an economically important species, but has been regarded as endangered in Sweden. My inventory has increased the number of reported localities from 3 to 31. It has long been debated whether T. aestivum and T. uncinatum are conspecific or not, so a clarification would help conservation biology and cultivation. My study included 117 fruit bodies of both taxa from 8 countries. The phylogenetic (ITS) and microscopic analyses showed that the two taxa were synonyms and that the spore reticulum height, used to separate the taxa, is not diagnostic. T. aestivum was clearly different from T. mesentericum, which I reported new to Sweden. The Gotland T. aestivum population was genetically distinct (RAPD) from other European specimens. The genetic variation suggested sexual reproduction. The habitat of 18 T. aestivum sites on Gotland were analysed and compared with data from France. No striking functional differences in soil chemistry were found, so a possible T. aestivum ecotype on Gotland would rather be an adaptation to the colder and drier climate. Selecting local T. aestivum inoculum for truffle orchards in Northern Europe could be important for successful truffle production. In 1999, 10 experimental truffle orchards with a total of 240 oak and hazel seedlings were established on Gotland, and as a result of this project 3000 commercial oak seedlings were planted in 2000-2001. In 2004, T. aestivum mycorrhiza was still present in all of the 22 orchards studied on Gotland, some in soils different from natural habitats. In addition, the project has also generated a truffle cultivation association, a truffle company, truffle dog breeding and export of T. aestivum to France.