Made available in DSpace on 2014-06-11T19:23:03Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-05-18Bitstream added on 2014-06-13T20:49:53Z : No. of bitstreams: 1 apazaquevedo_ae_me_rcla.pdf: 800607 bytes, checksum: 267307790610778739a78e2fefb26944 (MD5) / Os efeitos de borda incluem mudanças abióticas e bióticas nas condições ambientais, as quais afetam os padrões fenológicos das plantas. Comparamos a fenologia reprodutiva (quanto a data, duração, amplitude e sincronia) e o sucesso reprodutivo (medido pela conversão de flores em frutos fruit set) de Attalea geraensis e Syagrus petraea, entre borda e interior em um fragmento de Cerrado sensu stricto em Itirapina, estado de São Paulo, Brasil. Considerando as mudanças tanto abióticas quanto bióticas nos ambientes de borda em relação aos de interior, esperamos encontrar diferenças fenológicas entre ambientes. A caracterização do microclima local apresentou diferenças entre borda e interior na temperatura, umidade relativa, intensidade luminosa e abertura do dossel, tanto na estação úmida quanto na seca (exceto para abertura do dossel na estação seca, possivelmente pela queda de folhas no Cerrado). Attalea geraensis floresceu principalmente na estação úmida e frutificou o ano todo. Syagrus petraea floresceu e frutificou continuamente, com um pico de floração e frutificação em Outubro e Dezembro respectivamente. Ambas as espécies não apresentaram diferenças temporais significativas na fenologia reprodutiva entre borda e interior, o mesmo ocorrendo para duração, sincronia e sucesso reprodutivo. A reprodução vegetativa pode ter atenuado as diferenças entre as condições de borda e interior em Syagrus. A maior produção de inflorescências estaminadas em Attalea na borda pode estar relacionada com a elevada intensidade de luz neste ambiente. Características da borda tais como uma vegetação mais aberta, um baixo contraste em relação ao ambiente adjacente e, por outro lado, uma elevada abundância de indivíduos e longa duração das fenofases reprodutivas nestas espécies, poderia ter conduzido à resposta neutra observada. / Edge effects include both abiotic and biological changes on environmental conditions that affect plant phenological patterns. We compared the reproductive phenology (in terms of time, duration, amplitude and synchrony), and the reproductive success (fruit set) of Attalea geraensis and Syagrus petraea, between the edge and interior of a fragment of Cerrado sensu estricto (a savanna vegetation), at Itirapina, São Paulo State, Brazil. Considering both abiotic and biological changes on the edge in relation to the interior, we hope to find phenological differences between these environments. A local microclimatic characterization showed differences between edge and interior on temperature, relative humidity, light intensity and canopy openness in both wet and dry seasons (except for canopy openness in the dry season possibly due to the leaffall in the Cerrado). Attalea flowered mainly in the wet season and fruited all year round. Syagrus flowered and fruited continually, with a flower and fruit peak in October and December, respectively. Both species did not present temporal significant differences between edge and interior with regard to the reproductive phenology, duration, synchrony and fruit set. Any differences between edge and interior conditions could have been buffered by the vegetative reproduction in Syagrus. With regard to Attalea, the higher production of staminate inflorescences on the edge may be related to the greater light intensity in this environment. Edge characteristics such as the open structure of the vegetation and the low contrast with the adjacent environment, as well as the high abundance of individuals and long duration of the reproductive phenophases in these species, could have led to the neutral response observed.

Orientador: Leonor Patricia Cerdeira Morellato / Banca: Vânia Regina Pivello / Banca: Marco Antonio de Assis / Artigo seguindo as normas da revista Journal of Tropical Ecology / Artigos em inglês e português / Resumo: Os efeitos de borda incluem mudanças abióticas e bióticas nas condições ambientais, as quais afetam os padrões fenológicos das plantas. Comparamos a fenologia reprodutiva (quanto a data, duração, amplitude e sincronia) e o sucesso reprodutivo (medido pela conversão de flores em frutos fruit set) de Attalea geraensis e Syagrus petraea, entre borda e interior em um fragmento de Cerrado sensu stricto em Itirapina, estado de São Paulo, Brasil. Considerando as mudanças tanto abióticas quanto bióticas nos ambientes de borda em relação aos de interior, esperamos encontrar diferenças fenológicas entre ambientes. A caracterização do microclima local apresentou diferenças entre borda e interior na temperatura, umidade relativa, intensidade luminosa e abertura do dossel, tanto na estação úmida quanto na seca (exceto para abertura do dossel na estação seca, possivelmente pela queda de folhas no Cerrado). Attalea geraensis floresceu principalmente na estação úmida e frutificou o ano todo. Syagrus petraea floresceu e frutificou continuamente, com um pico de floração e frutificação em Outubro e Dezembro respectivamente. Ambas as espécies não apresentaram diferenças temporais significativas na fenologia reprodutiva entre borda e interior, o mesmo ocorrendo para duração, sincronia e sucesso reprodutivo. A reprodução vegetativa pode ter atenuado as diferenças entre as condições de borda e interior em Syagrus. A maior produção de inflorescências estaminadas em Attalea na borda pode estar relacionada com a elevada intensidade de luz neste ambiente. Características da borda tais como uma vegetação mais aberta, um baixo contraste em relação ao ambiente adjacente e, por outro lado, uma elevada abundância de indivíduos e longa duração das fenofases reprodutivas nestas espécies, poderia ter conduzido à resposta neutra observada. / Abstract: Edge effects include both abiotic and biological changes on environmental conditions that affect plant phenological patterns. We compared the reproductive phenology (in terms of time, duration, amplitude and synchrony), and the reproductive success (fruit set) of Attalea geraensis and Syagrus petraea, between the edge and interior of a fragment of Cerrado sensu estricto (a savanna vegetation), at Itirapina, São Paulo State, Brazil. Considering both abiotic and biological changes on the edge in relation to the interior, we hope to find phenological differences between these environments. A local microclimatic characterization showed differences between edge and interior on temperature, relative humidity, light intensity and canopy openness in both wet and dry seasons (except for canopy openness in the dry season possibly due to the leaffall in the Cerrado). Attalea flowered mainly in the wet season and fruited all year round. Syagrus flowered and fruited continually, with a flower and fruit peak in October and December, respectively. Both species did not present temporal significant differences between edge and interior with regard to the reproductive phenology, duration, synchrony and fruit set. Any differences between edge and interior conditions could have been buffered by the vegetative reproduction in Syagrus. With regard to Attalea, the higher production of staminate inflorescences on the edge may be related to the greater light intensity in this environment. Edge characteristics such as the open structure of the vegetation and the low contrast with the adjacent environment, as well as the high abundance of individuals and long duration of the reproductive phenophases in these species, could have led to the neutral response observed. / Mestre

Call number: LD2668 .T4 1985 K87 / Master of Science / Agronomy

Most of the species of the family Rubiaceae with flowers arranged in head inflorescences are currently classified in three distantly related tribes, Naucleeae (subfamily Cinchonoideae) and Morindeae and Schradereae (subfamily Rubioideae). Within Morindeae the type genus Morinda is traditionally and currently circumscribed based on its head inflorescences and syncarpous fruits (syncarps). These characters are also present in some members of its allied genera, raising doubts about the monophyly of Morinda. We perform Bayesian phylogenetic analyses using combined nrETS/nrITS/trnT-F data for 67 Morindeae taxa and five outgroups from the closely related tribes Mitchelleae and Gaertnereae to rigorously test the monophyly of Morinda as currently delimited and assess the phylogenetic value of head inflorescences and syncarps in Morinda and Morindeae and to evaluate generic relationships and limits in Morindeae. Our analyses demonstrate that head inflorescences and syncarps in Morinda and Morindeae are evolutionarily labile. Morinda is highly paraphyletic, unless the genera Coelospermum, Gynochthodes, Pogonolobus, and Sarcopygme are also included. Morindeae comprises four well-supported and morphologically distinct major lineages: Appunia clade, Morinda clade (including Sarcopygme and the lectotype M. royoc), Coelospermum clade (containing Pogonolobus and Morinda reticulata), and Gynochthodes-Morinda clade. Four possible alternatives for revising generic boundaries are presented to establish monophyletic units. We favor the recognition of the four major lineages of Morindeae as separate genera, because this classification reflects the occurrence of a considerable morphological diversity in the tribe and the phylogenetic and taxonomic distinctness of its newly delimited genera.

Kangaroo paw inflorescences stored dry at 0 to 1 Degrees Celsius for 14 days have been found previously to have substantially reduced post-storage vase life. In this project, experiments were conducted to quantify the vase life of dry, stored Kangaroo paw flowers following storage at either 0, 7.5 or 13 Degrees Celsius for up to four weeks. the aim of these experiments was to determine a dry storage temperature suitable for commercial use. experiments were carried out using two cultivars of Kangaroo paw, 'Bush Dawn' and 'Big Red'. For each cultivar, vase life was assessed by (1) determining the time taken for each flower to lose 20% of its initial fresh weight and (2) determining the time taken for 10% of the inflorescence to become to discoloured. Vase life studies were carried out a 22 Degrees Celsius prior to and following removal from low temperature storage and flowers were weighed, inflorescence colour determined and chlorophyll fluorescence parameters Fo, minimal fluorescence emission, and Fm, maximum fluorescence emission were determined.

Viticultural practices such as trunk girdling and shoot topping along with defoliation, shading and node number per vine treatments were used to alter the carbohydrate physiology of mature Chardonnay grapevines growing in the cool climate of Canterbury, New Zealand. The timing of vine defoliation in the season previous to fruiting decreased concentrations of over-wintering carbohydrate reserves (mostly starch) in both the trunks and roots of grapevines. Roots were particularly sensitive, with defoliation as early as 4 weeks after bloom in the previous season reducing starch concentrations to 1.5%Dwt at bud burst compared with 17%Dwt in non-defoliated vines. In contrast, partial vine defoliation as early as bloom in the previous season reduced root starch concentrations to 4-7%Dwt at bud burst compared with 15%Dwt in non-defoliated vines. Vine shading and trunk girdling treatments at bloom in the previous season, resulted in small reductions in root starch concentrations (16%Dwt) compared with non-shaded and non-girdled vines (19%Dwt), but shoot topping did not. Study across three growing seasons established that higher concentrations of over-wintering trunk and root carbohydrate reserves were associated with warmer and sunnier weather in the previous growing season. Individual shoot leaf removal at either the beginning or towards the end of the inflorescence initiation period, reduced shoot starch concentrations to 3-6%Dwt compared with 11 %Dwt for no leaf removal, such reductions persisted through to the following season. Shoot topping at the start of the initiation period had no effect on shoot carbohydrate accumulation, but trunk girdling temporarily increased shoot starch concentrations during the first 31 days after treatment. Reductions in over-wintering trunk and root carbohydrate reserves were associated with a reduction in inflorescences per shoot and flowers per inflorescence in the following season, the reduction as much as 50% compared with non carbohydrate stressed vines. While there were strong linear or curvilinear relationships between the concentration of starch in trunks and roots at bud burst and inflorescences per shoot and flowers per inflorescence, in case the of inflorescences per shoot, there was not an immediate cause and effect because inflorescences were initiated in the previous season. Individual shoot leaf removal during the inflorescence initiation period illustrated that leaf removal directly inhibited the initiation of inflorescences in latent buds. Shoot carbohydrate measurements showed a strong curvilinear relationship to the number of inflorescences per shoot, with a threshold starch concentration of 10-12%Dwt during the inflorescence initiation period required for a maximum number of inflorescences per shoot. Furthermore, examination of individual node positions emphasised the importance of the subtending leaf on the initiation of inflorescences within the latent bud. The number of inflorescences per shoot post bud burst was reduced on vines that were both carbohydrate reserve stressed (by previous season's defoliation) and had a high node (108) number retained per vine after winter pruning compared with little or no reduction in inflorescences per shoot on carbohydrate reserve stressed vines that had a low (20) node number per vine. The reduction in inflorescences per shoot on high node vines was associated with reduced carbohydrate reserves and reduced shoot vigour (thinner and lighter shoots). Flowers per inflorescence were reduced by as much 50% in response to lower overwintering carbohydrate reserves. Fewer flowers per inflorescence were attributed to a reduction in primary branching of the inflorescence and also a reduction in flowers per branch. Strong linear relationships between the concentrations of starch in trunks and roots and flowers per inflorescence indicate that the determination of flowers per inflorescence, unlike inflorescences per shoot, may be dependent on the level of overwintering carbohydrate reserves. This is most likely due to changes in branching of the inflorescence and individual flower formation occurring during the bud burst period. Per cent fruitset was not affected by reductions in carbohydrate reserves, so fewer inflorescences per shoot and flowers per inflorescence resulted in reduced vine yield. The findings of this thesis indicate that changes in the level of carbohydrate production and partitioning in response to a range of viticultural management practices and seasonal weather contribute to seasonal variation in grapevine flowering and yields in New Zealand's cool climate environment. The relationships between carbohydrate reserves and flowering illustrate the potential to use this information to predict grapevine flowering and forecast yields. The practical implications of this research illustrate that the viticulturist must manage grapevines not only for the current crop, but also for subsequent crops by maintaining sufficient carbohydrate reserves for balanced growth flowering and fruiting from season to season.

LFY of Arabidopsis is a member of a unique plant specific transcription factor family. It is involved in giving meristem a determinate floral fate by the activation of floral organ identity genes and preventing inflorescence meristem identity. RFL is a homolog of FLO/LFY in rice. Studies from our lab on rice RFL, based on the effects of knockdown or overexpression, showed its major functions are in timing the conversion of SAM to IM and to prevent the premature conversion of branch meristem to spikelets. Additionally roles in vegetative axillary meristem specification have been also been identified in laboratory. Here, we attempt to delineate molecular pathways directly regulated by RFL as a transcription factor controlling inflorescence and floral development in rice. Part I: Identification of global target genes bound by RFL in developing rice inflorescences We carried out ChIP sequencing of the DNA bound by RFL in panicles (01.-0.3cm stage) using anti-RFL antibody. DNA sequences in one library pool were analyses by the MACS algorithm (FDR<0.01), to find 8000 binding sites while the SPP algorithm identified 5000 enriched peaks. These mapped to 2500 or 2800 gene-associated loci respectively, 617 of which were common loci to both pipelines. Several RFL bound gene loci were homologs of Arabidopsis thaliana LFY gene targets. Such gene targets underscore conserved downstream targets for LFY-proteins in evolutionarily very distinct species. AtLFY is known to bind variants of CCANT/G cis element classified as primary, inflorescence or seedling type. We scanned for these three types of cis elements at 123 RFL bound genes with likely functions in flowering. For a few of these 123 rice loci we find one of these cis motifs (p-value<0.001) in RFL bound ChIP-seq data. To validate these targets of RFL, we adopted in vitro DNA-protein binding assays with bacterially purified RFL protein. We confirm RFL target interactions with some genes implicated in flowering time, others in photoperiod triggered flowering, circadian rhythm, gibberellin hormone pathway, inflorescence development and branching. The in vitro experiments hint different RFL-DNA binding properties as compared to Arabidopsis LFY. We report binding to sequences at rice gene loci that are unique targets. Part II: Pathways regulated by RFL for reproductive transition and panicle development To co-relate DNA binding of RFL to target loci with changes in their gene expression, expression studies were taken up for selected set of genes implicated in rice flowering transition and panicle architecture. To study in planta and tissue specific gene regulation by RFL we raised RFL dsRNAi transgenics. Comparative transcript analysis in these RFL partial knockdown lines and matched wild type tissues reveal that RFL is an activator for some genes and repressor for other gene targets. We also examined if the gene expression effects of RFL knockdown can be reversed by induced complementation with an RFL-GR protein. We raised transgenics plants with a T-DNA ubi:RFL-GR, 35S CaMV:amiR RFL for these experiments. In planta target gene transcript levels were assessed in various conditions conditions. These studies validate rice RFL as an activator of some panicle architecture genes. Part III: Analysis of endogenous RFL protein in WT rice tissues Studies in Arabidopsis and in petunia with LFY and AFL, respectively, implicate these some abnormal mobility as compared to their predicted molecular weight when overexpressed. We studied endogenous RFL protein abundance in planta, adopting western analysis with anti-RFL antibody. We consistently identify two prominent cross reacting bands in different tissues which can be also be pulled-down from whole nuclear extracts of panicle and axillary meristem tissues. We speculate on likely modifications and possible functions for the same.