Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal

The arbuscular mycorrhizal (AM) association results from a successful interaction between the genomes of the two symbiotic partners. In this context, the aim of my research was to better characterize the role of the late stage symbiosis-related pea genes PsSym36, PsSym33 and PsSym40 in the functional AM (i) by investigating the effect of mutations in the three genes on fungal and plant gene responses and (ii) by creating conditions for the localization of two of the genes, PsSym36 and PsSym40, on the pea genetic map for future map-based cloning. The expression of a subset of ten fungal and eight plant genes,previously reported to be activated during mycorrhiza development, was compared in Glomus intraradices-inoculated roots of wild type and Pssym36, Pssym33 and Pssym40 mutant pea plants. Most of the fungal genes were down-regulated in roots of the Pssym36 mutant where arbuscule formation is defective, and several were upregulated with more rapid fungal development in roots of the Pssym40 mutant. Microdissection of mycorrhizal PsSym40 roots corroborated preferential expression of the three G. intraradices genes SOD, DESAT and PEPISOM in arbuscule-containing cells. Inactivation of PsSym36 also resulted in down regulation of plant genes whilst mutation of the PsSym33 and PsSym40 genes affected plant gene responses in a more time-dependent way. Results thus indicate an implication of the investigated pea SYM genes in the modulation of plant and fungal molecular interactions linked to signaling, nutrient exchange or stress response regulation during AM symbiosis formation and functioning. Conditions for localization of the PsSym36 and PsSym40 genes on the pea genetic map were developed for their future map-based cloning. Based on the molecular markers obtained, it was possible to conclude that localization of the PsSym40 gene most likely resides outside the linkage groups I, II, III or V of the genetic map of pea.

No description available.

Stretches of forest along the Limpopo and Shashe Rivers have been classified as a unique forest type in the vegetation of South Africa and are considered as being "critically endangered" by the South African Biodiversity Institute. Roughly 400 hectares of this riverine forest area inside the western section of the Mapungubwe National Park (MNP), a UNESCO World Heritage site, were deforested and therefore degraded due to previous agricultural cultivation practices. Given the extent of forest degradation that has occurred, the restoration of this area by means of the re–vegetation of indigenous trees to its former composition is one of the objectives of the MNP's management plan. The successful establishment of tree seedlings, especially in semi–arid systems, is however presented with a wide range of constraints and limiting conditions, which often result in very high mortality rates during restoration projects. An experimental exclosure, as identified by South African National Parks (SANParks), was therefore fenced off inside the degraded old lands to act as a demonstration site for the restoration of indigenous trees. A pilot study conducted in 2006, involved the transplantation of selected indigenous tree species with the aim of evaluating suitable re–vegetation technologies. The research contained in this dissertation was also conducted inside the experimental exclosure, where recommendations derived from the pilot study were evaluated, including the assessment of new re–vegetation technologies to enhance the establishment of the indigenous trees. This study was therefore a follow–up project which involved both field– and greenhouse trials. Seedlings of the following species were either transplanted into the experimental exclosure (field trial) or cultivated inside a controlled environment in the greenhouse at the North–West University: Acacia xanthophloea Benth. (fever tree), Berchemia discolor (Klotzsch) Hemsl. (brown–ivory), Combretum imberbe Wawra (leadwood), Faidherbia albida (Delile) A. Chev. (ana tree), Philenoptera violacea (Klotzsch) Schrire (apple–leaf), Salvadora australis Schweick. (narrow–leaved mustard tree) and Xanthocercis zambesiaca (Baker) Dumaz–le–Grand (nyala tree). During the follow–up study the effects of various enhancement treatments were tested regarding the survival, growth and physiological performance of seedlings in both the field– and greenhouse trials. The enhancement treatments consisted of the addition of compost and indigenous arbuscular mycorrhizal fungi (AMF). In addition, seedlings transplanted during the pilot study, which did not include enhancement treatments, were also monitored for establishment and growth. The potential use of established Acacia tortilis Hayne trees to facilitate growth and establishment and to act as "nursing plants", was also assessed. In addition, various pre–sowing treatments were also applied to seeds of selected tree species in the greenhouse to assess the germination rate. The survivorship and growth of seedlings in both the field– and greenhouse trial were determined by using three growth parameters, namely "stem diameter at the base", "stem diameter 30 cm from the base", and "height of the tree in its natural growth form". Chlorophyll fluorescence induction (JIP test) was measured on seedlings in both trials, using the multi–parametric expression, namely performance index (PIABS), as a measure of the overall vitality of the plants of each species–treatment combination. Physical and chemical analyses were carried out on the soil inside the experimental exclosure. Basic descriptive statistics were used to analyse seedling survival and germination rates, and a two–way analysis of variance (ANOVA) was used to determine the statistical significant effects of the various enhancement treatments on diameter growth in each species (p < 0.05). Fluorescence data were processed using the Biolyzer software and significant effects in each species were determined using the Student's t–test (p < 0.05). Multivariate data ordinations using the CANOCO package were used to determine the differences in soil types inside the experimental exclosure. Moisture stress due to transplantation shock, competition with dense grass cover and herbivory, resulted in an overall 55.8% seedling survival rate and negative stem diameter growth for transplanted seedlings in the field. In comparison, seedlings cultivated in the greenhouse had much higher survival rates and showed positive stem diameter growth. Most species in the greenhouse showed higher growth rates and significantly higher vitality values when planted with enhancement treatments. The responses of transplanted seedlings to the enhancement treatments were very species–specific in the field trials. Based on these results, it was concluded that the enhancement treatments were beneficial with regard to the establishment and growth of most of the species. The beneficial effect was however cancelled out by the various abiotic and biotic factors encountered in the natural environment. Seedlings transplanted in the understory of established pioneer A. tortilis trees had much lower survival rates as the extensive root system of A. tortilis most likely out–competed the transplanted seedlings for moisture and nutrients. Many seedlings were also predated by insects or small mammals which reduced the growing potential. The germination trials recorded the highest germination rates for most species when germinated in the compost–containing treatments. These trials also indicated that all of the investigated species showed higher survival rates when pre–sowing treatments, such as soaking, mechanical scarification and removing the seed from fruit, were applied. Various recommendations emphasising long–term monitoring, proper maintenance and after–care of future restoration efforts are made. These include experimental layout of exclosure plots and pretransplantation treatments of seedlings while cultivated in the nursery. During this study, the experimental exclosure was also used as a demonstration site for training and capacity building for SANParks personnel and students from academic institutions. / Thesis (M.Sc. (Environmental Science))--North-West University, Potchefstroom Campus, 2011.

Stretches of forest along the Limpopo and Shashe Rivers have been classified as a unique forest type in the vegetation of South Africa and are considered as being "critically endangered" by the South African Biodiversity Institute. Roughly 400 hectares of this riverine forest area inside the western section of the Mapungubwe National Park (MNP), a UNESCO World Heritage site, were deforested and therefore degraded due to previous agricultural cultivation practices. Given the extent of forest degradation that has occurred, the restoration of this area by means of the re–vegetation of indigenous trees to its former composition is one of the objectives of the MNP's management plan. The successful establishment of tree seedlings, especially in semi–arid systems, is however presented with a wide range of constraints and limiting conditions, which often result in very high mortality rates during restoration projects. An experimental exclosure, as identified by South African National Parks (SANParks), was therefore fenced off inside the degraded old lands to act as a demonstration site for the restoration of indigenous trees. A pilot study conducted in 2006, involved the transplantation of selected indigenous tree species with the aim of evaluating suitable re–vegetation technologies. The research contained in this dissertation was also conducted inside the experimental exclosure, where recommendations derived from the pilot study were evaluated, including the assessment of new re–vegetation technologies to enhance the establishment of the indigenous trees. This study was therefore a follow–up project which involved both field– and greenhouse trials. Seedlings of the following species were either transplanted into the experimental exclosure (field trial) or cultivated inside a controlled environment in the greenhouse at the North–West University: Acacia xanthophloea Benth. (fever tree), Berchemia discolor (Klotzsch) Hemsl. (brown–ivory), Combretum imberbe Wawra (leadwood), Faidherbia albida (Delile) A. Chev. (ana tree), Philenoptera violacea (Klotzsch) Schrire (apple–leaf), Salvadora australis Schweick. (narrow–leaved mustard tree) and Xanthocercis zambesiaca (Baker) Dumaz–le–Grand (nyala tree). During the follow–up study the effects of various enhancement treatments were tested regarding the survival, growth and physiological performance of seedlings in both the field– and greenhouse trials. The enhancement treatments consisted of the addition of compost and indigenous arbuscular mycorrhizal fungi (AMF). In addition, seedlings transplanted during the pilot study, which did not include enhancement treatments, were also monitored for establishment and growth. The potential use of established Acacia tortilis Hayne trees to facilitate growth and establishment and to act as "nursing plants", was also assessed. In addition, various pre–sowing treatments were also applied to seeds of selected tree species in the greenhouse to assess the germination rate. The survivorship and growth of seedlings in both the field– and greenhouse trial were determined by using three growth parameters, namely "stem diameter at the base", "stem diameter 30 cm from the base", and "height of the tree in its natural growth form". Chlorophyll fluorescence induction (JIP test) was measured on seedlings in both trials, using the multi–parametric expression, namely performance index (PIABS), as a measure of the overall vitality of the plants of each species–treatment combination. Physical and chemical analyses were carried out on the soil inside the experimental exclosure. Basic descriptive statistics were used to analyse seedling survival and germination rates, and a two–way analysis of variance (ANOVA) was used to determine the statistical significant effects of the various enhancement treatments on diameter growth in each species (p < 0.05). Fluorescence data were processed using the Biolyzer software and significant effects in each species were determined using the Student's t–test (p < 0.05). Multivariate data ordinations using the CANOCO package were used to determine the differences in soil types inside the experimental exclosure. Moisture stress due to transplantation shock, competition with dense grass cover and herbivory, resulted in an overall 55.8% seedling survival rate and negative stem diameter growth for transplanted seedlings in the field. In comparison, seedlings cultivated in the greenhouse had much higher survival rates and showed positive stem diameter growth. Most species in the greenhouse showed higher growth rates and significantly higher vitality values when planted with enhancement treatments. The responses of transplanted seedlings to the enhancement treatments were very species–specific in the field trials. Based on these results, it was concluded that the enhancement treatments were beneficial with regard to the establishment and growth of most of the species. The beneficial effect was however cancelled out by the various abiotic and biotic factors encountered in the natural environment. Seedlings transplanted in the understory of established pioneer A. tortilis trees had much lower survival rates as the extensive root system of A. tortilis most likely out–competed the transplanted seedlings for moisture and nutrients. Many seedlings were also predated by insects or small mammals which reduced the growing potential. The germination trials recorded the highest germination rates for most species when germinated in the compost–containing treatments. These trials also indicated that all of the investigated species showed higher survival rates when pre–sowing treatments, such as soaking, mechanical scarification and removing the seed from fruit, were applied. Various recommendations emphasising long–term monitoring, proper maintenance and after–care of future restoration efforts are made. These include experimental layout of exclosure plots and pretransplantation treatments of seedlings while cultivated in the nursery. During this study, the experimental exclosure was also used as a demonstration site for training and capacity building for SANParks personnel and students from academic institutions. / Thesis (M.Sc. (Environmental Science))--North-West University, Potchefstroom Campus, 2011.

Certain crop plants are susceptible to pathogens or unable to develop efficient microbial symbioses. These crops adversely impact soil biological quality with consequences on plant health and productivity of cropping systems. Chickpea is a rotational pulse crop with two types: kabuli and desi, and several cultivars. Cultivation of chickpea has inconsistent effects on soil microbial communities and subsequent wheat crops. I conducted field studies and used high throughput molecular analyses to explore the variations among chickpeas to identify cultivars developing fungal communities that are conducive to plant health and productivity. I also carried out greenhouse studies and used biochemical analyses to investigate the response of chickpea cultivars to arbuscular mycorrhizal (AM) fungi and non-AM fungal endophytes and identify the influence of root and root metabolites on the endophytic and pathogenic fungi. Cultivars and types of chickpeas and environmental conditions promoted different fungal communities in the root endosphere. Funneliformis and Claroideoglomus were the dominant AM fungal genera and Fusarium and Alternaria were the dominant non-AM fungal genera in the roots of chickpea. The roots of cultivars CDC Corrine, CDC Cory and CDC Anna hosted the most diverse fungal communities in contrast to CDC Alma and CDC Xena roots which hosted the least diverse communities. Plant response to AM and non-AM fungal endophytes varied with genotype and type of chickpea. The root symbiosis effectively promoted plant growth in CDC Cory, CDC Anna and CDC Frontier and stimulated nitrogen fixation in CDC Corrine. Cultivars of chickpea responded differently to dual inoculation of the AM and non-AM fungal endophytes. Co-inoculation with AM and non-AM fungal endophytes had additive effects on CDC Corrine, CDC Anna and CDC Cory but non-AM fungal endophytes reduced the positive effect of AM fungi in Amit and CDC Vanguard. Desi chickpea appeared to form more efficient symbioses with soil fungal resources than kabuli chickpea. Protein(s) up-regulated in the mycorrhizal roots of the desi chickpea CDC Anna suppressed the growth of the fungal endophytes Trichoderma harzianum and Geomyces vinaceus and of the pathogens Fusarium oxysporum and Rhizoctonia sp. The formation of AM symbiosis decreased the production of root bioactive metabolites soluble in 25% methanol. Some of the root metabolites stimulated the growth of Trichoderma harzianum and Geomyces vinaceus, and a few inhibited Rhizoctonia sp. and Fusarium oxysporum. A few metabolites with contrasting effects on the different fungal species were detected. The non-protein phytochemicals had selective effects on the endophytes and pathogens whereas the antifungal proteins of mycorrhizal roots were non-selective. Overall the study reveals a "genotype effect" of chickpea on the soil microbiota suggesting the possibility to improve the performance of this crop through the selection of genotypes improving the communities of root associated fungi, by associating and responding to beneficial fungi and repressing the pathogens.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2007. / Härtill 5 uppsatser.

Made available in DSpace on 2014-06-11T19:35:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-08-30Bitstream added on 2014-06-13T19:05:40Z : No. of bitstreams: 1 neto_mj_dr_ilha.pdf: 993776 bytes, checksum: 2b507122c2d5ec15ebaf77777529b841 (MD5) / Universidade Estadual Paulista (UNESP) / Este trabalho foi realizado em dois remanescentes de Cerrado sentido restrito conhecidos por Reserva do Exército e Parque Municipal Capivaras; e numa área urbanizada denominada Vila Piloto, localizados no Município de Três Lagoas - MS. Nesta última foi realizado o levantamento de plantas ruderais. Nas três áreas fez-se o levantamento da diversidade florística e coletou-se amostras de plantas em fase jovem para verificação de colonização micorrízica arbuscular. Amostras compostas de solo também foram coletadas para contagem de esporos e análise das características químicas do solo. A área de Reserva do Exército mostrou um total de 397 espécies, distribuídas em 241 gêneros e 70 famílias. Das 44 espécies submetidas à análise de colonização micorrízica, 17 tiveram muito alta, 18 alta, oito baixa e uma ausente. O Parque Capivaras exibiu 449 espécies, distribuídas em 277 gêneros e 96 famílias. Das 44 espécies submetidas à análise de colonização micorrízica, 22 tiveram muito alta, 15 alta, uma baixa e seis ausente. Para a Vila Piloto foram identificadas 344 espécies distribuídas em 201 gêneros e 61 famílias, três espécimes determinados apenas em nível de gênero, das 344 espécies 281 são nativas do Brasil e 76 são típicas de cerrado ou cerradão. Das 50 espécies de plantas ruderais escolhidas para verificação da colonização micorrízica, 27 exibiram colonização muito alta, três alta, duas média, onze baixa e sete espécies não apresentaram colonização micorrízica. Os solos das áreas estudadas se apresentam com teores médios para alumínio e matéria orgânica. A média de esporos por 100g de solos foi de 53 para o Exército e 48 para o Parque Capivaras, permitindo sugerir que as áreas estão em equilíbrio. Para a Vila Piloto os resultados da amostragem do solo para os dois pontos coletados revelaram uma fertilidade que pode ser... / This research was accomplished in two restricted sense cerrado remnants, one of them known as the Military Reserve and the other the Municipal Park of Capivaras. The other area was in an urbanized region named Vila Piloto, located in Três Lagoas - MS County, where a floristic survey of ruderal plants was made. In all three areas, a survey of floristic biodiversity was done and samples of young plants were collected to verify arbuscular mychorhizal colonization. Soil samples were also taken for counting spores and for analyzing its chemical characteristics. The Military Reserve displayed a total of 397 species, distributed in 241 genera and 70 families. Of the 44 species submitted to mychorrhizal colonization analyses, 17 were very high, 18 high, eight low and one absent. The Capivaras Park displayed 449 species, distributed in 277 genera and 96 families. Of the 44 species submitted to the mychorhizal colonization analysis, 22 had very high, 15 high, one had low and six had no colonization. For Vila Piloto, 344 species were identified and distributed in 201 genera and 61 families, and three specimens determined only in the genus level. Of the 344 species, 281 are natives to Brazil and 76 are typical of Cerrado or Cerradão. Fifty species from ruderal plants were chosen for verification of the mychorhizal colonization, of which 27 species displayed very high colonization, three high, two medium, eleven low and seven species did not present mychorhizal colonization. The soil of the studied area has medium content for aluminum and organic material. The average number of spores per 100g of soil was 53 for the Reserve and 48 for the Park, suggesting that the areas were in equilibrium. The results from Vila Piloto soil samples collected from two points revealed a fertility that can be considered higher than the typical Cerrado and an average number of FMA spores of 152 per 100g of dry soil ... (Complete abstract click electronic access below)

Made available in DSpace on 2015-03-26T13:51:44Z (GMT). No. of bitstreams: 1 01 - capa_abstract.pdf: 58664 bytes, checksum: 66cb47131cc46bcd2d5d263065f54c20 (MD5) Previous issue date: 2008-07-29 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The objective of this work was to evaluate the effects of the arbuscular mycorrhizal fungus (AMF), Glomus clarum, multiplied monoxenically in transformed carrot roots, on the growth, survival, mycorrhizal colonization and root development of micropropagated plantlets in different stages of rooting. Inoculation was performed in vitro and ex vitro conditions. Micropropagated plantlets with 0, 14 or 21 days maintained in rooting medium, supplemented or not with 1 mg L-1 of Indolbutiric acid (IBA), were transferred to a substrate composed by sand:soil:vermiculite (1:1/2:1). The in vitro system allowed the establishing mycorrhizal association, but no stimulatory effect on the development of shoot or root by mycorrhizal inoculation was observed. The period of time and addition of IBA did not affect plant growth. In ex vitro system, the stimulatory effects of arbuscular mycorrhizal association were evident in all evaluated characteristics, except to plant height. Plants that were not submitted to rooting showed growth similar or superior to those that were maintained in the rooting media, independent of IBA addition. Inoculated plants were shown to be more efficient at nutrient absorption, especially to phosphate. The arbuscular mycorrhizal association promotes beneficial effects when inoculation is performed ex vitro and the best period for inoculation of physic nut seedlings is in the beginning of acclimatization, without in vitro rooting phase. Inoculation of physic nut with arbuscular mycorrhizal fungi showed to be an important tool for micropropagated seedlings production. / O objetivo deste trabalho foi avaliar o efeito da inoculação do fungo micorrízico arbuscular (FMA), Glomus clarum, multiplicado monoxenicamente em raízes de cenoura transformadas, sobre o crescimento, a sobrevivência, a colonização micorrízica e o desenvolvimento radicular de plantas micropropagadas de pinhão-manso em diferentes estádios de enraizamento. A inoculação foi efetuada em condições in vitro e ex vitro. Plantas micropropagadas de pinhão-manso com 0, 14 ou 21 dias de permanência em meio de enraizamento, suplementado ou não com 1 mg L-1 de ácido indol-butírico (AIB), foram transferidas para substrato areia lavada:solo:vermiculita (1:1/2:1). O sistema in vitro utilizado permitiu o estabelecimento da associação micorrízica, mas não foi possível observar efeitos estimuladores da inoculação sobre o crescimento e desenvolvimento radicular das plantas. O tempo de permanência em meio de enraizamento e a adição de AIB também não afetaram o crescimento das plantas. No sistema ex vitro os efeitos estimuladores das micorrizas arbusculares foram evidenciados em todas as características relacionadas ao crescimento, com exceção da altura das plantas. As plantas que não foram submetidas à etapa de enraizamento mostraram crescimento semelhante ou superiores àquelas submetidas à etapa de enraizamento, independente da adição do AIB. As plantas inoculadas com G. clarum mostraram-se também eficientes na absorção de nutrientes, principalmente de fósforo. Pode-se concluir que os efeitos estimuladores das micorrizas arbusculares foram evidenciados quando foi realizada a inoculação ex vitro dessas plantas e que a melhor época de inoculação de J. curcas corresponde à fase de início da aclimatização, sem necessidade de passar pela fase de enraizamento in vitro. A inoculação com FMAs pode representar importante ferramenta para a produção de mudas micropropagadas de qualidade.

Orientador: Ana Maria Rodrigues Cassiolato / Banca: Luiz Antonio Graciolli / Banca: Gilberto Colodro / Resumo: O solo é um meio que engloba diferentes substâncias químicas e colóides e uma alta diversidade biológica. Estes componentes apresentam íntima relação funcional para sustentabilidade dos ecossistemas e, sua degradação, geralmente causada pela ação antrópica, acarreta um grande prejuízos ambientais e socioeconômicos para as gerações atuais e um enorme risco para as gerações futuras. Para reverter um processo como este, são necessárias intervenções por meio de estratégias como a revegetação. O objetivo do trabalho foi avaliar crescimento e colonização micorrízica do pinhão manso em solo decaptado que recebeu inoculo de fungos micorrizicos arbusculares, hidrogel e materiais orgânicos. O experimento foi conduzido de maio de 2008 a maio 2009, na Fazenda de Ensino, Pesquisa e Extensão (FEPE) da UNESP - Universidade Estadual Paulista, Campus de Ilha Solteira, no município de Selvíria-MS. O delineamento experimental foi o em blocos casualizado, em esquema fatorial 4x2x2, ou seja, 3 tratamentos com material orgânico (aguapé, composto e aguapé+composto), 2 tratamentos com hidrogel (com e sem adição) e 2 tratamentos de inoculação (com e sem inoculação) empregando solo proveniente de uma área preservada de cerrado como fonte de microrganimos, incluíndo fungos micorrízicos arbusculares, com 4 repetições e 5 plantas por tratamentos. O composto foi preparado com materiais de poda e esterco de bovino. Avaliou-se: o crescimento das plantas em 7 épocas diferentes, a caracterização química e número de esporos em 4 épocas, além da porcentagem de colonização micorrízica, presença de flores, número de ramos e de folhas e peso fresco e seco da parte aérea. O tratamento com hidrogel não mostrou interferência no crescimento de plantas, mas, assim como o solo-inóculo, aumentou a esporulação, a colonização micorrízica e a produção de matéria seca... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The soil is a medium that contain different chemical substances and colloids and a high biological diversity. These components have functional relationship on the sustainability of ecosystems and their degradation, usually caused by human action, which causes great socio-economic damage to the present generations and an enormous risk for the future generations. To reverse such process, action is needed using strategies, such as, revegetation. The objective of this study was to evaluate the growth and mycorrhiza colonization of Jatropha on decapitated soil that received organic materials and hydrogel. The experiment was conducted from May 2008 to May 2009, the Farm Education, Research and Extension (FEPE), UNESP - Univ. Estadual Paulista, Ilha Solteira Campus, located at Selvíria city-MS, Brazil. The experimental design was randomized blocks in factorial scheme 3x2x2, i.e., 3 treatments with organic materials (water hyacinth, compost and water hyacinth + compost), 2 hydrogel treatments (with and without addition) and 2 inoculations treatments (with and without inoculation) using natural soil from a preserved 'cerrado' area as a source of microorganisms, including mycorrhizal fungi, with 4 replications and 5 plants per each. The compound was prepared with materials pruning and cow dung. The growth of plants in 7 different times, the chemical characterization and number of spores in 4 times, and the percentage of mycorrhizal colonization, presence of flowers, branches and leaves and fresh and dry weight of air part was evaluated. Treatment with hydrogel showed no interference with the growth of plants; however, as well as the soilinoculum, they increased sporulation, root colonization and production of dry matter. The organic materials treatments positively altered the condition of the ground, plant growth, mycorrhizal colonization and sporulation; the improved performances... (Complete abstract click electronic access below) / Mestre