Fusarium subglutinans sensu lato is a complex of fungi, which are the causal agents of important diseases on a wide variety of plants. Two important diseases caused by F. subglutinans sensu lato are pitch canker and mango malformation. F. subglutinans sensu lato isolates causing pitch canker on pine trees have been described as a separate species, F. circinatum. whereas F. subglutinans sensu lato isolates associated with mango malformation have not been formally described. The objective of study was to clarify the taxonomy and population genetics of the pitch canker and mango malformation fungi residing in the Gibberellafujikuroi complex. The introductory chapter of this thesis provides a review of the taxonomic classifications used for Fusarium spp. in the G. fujikuroi complex. In addition, the current knowledge pertaining to the population structure of the pitch canker and mango malformation fungi is discussed. In the second chapter the occurrence of F. circinatum was investigated in Mexico. Fusarium isolates were collected from pine trees in Mexico and identified as F. circinatum. Morphology, sexual compatibility studies, pathogenicity tests and histone H3-RFLPs were used to identify and characterize this fungus. The pitch canker fungus, F. circinatum and its teleomorph, G. circinata has been recently described. However, the name G. circinata is invalid, because insufficient information was provided to characterize the type specimen in the description. Additional information and a selection of F. circinatum isolates were, therefore, obtained and studies were undertaken in order to validate the description of G. circinata. The teleomorph G. circinata was validated and morphological criteria were shown to clearly distinguish F. circinatum from other F. subglutinans sensu lato isolates. Chapter four presents a study aimed at better understanding relationships between populations of F. circinatum from different geographical areas. For this study co¬dominant molecular markers were developed. These were then used to determine the genetic diversity, genetic distance and migration between different F. circinatum populations. Analysis revealed a high diversity in the Florida population and a low diversity in the South African population. Genetic analysis also indicated that the South African F. circinatum population originated in Mexico. In chapter five, the influence of sexual reproduction on the F. circinatum populations sampled over ten years in South Africa were studied. Sexual compatibility, vegetative compatibility and allelic diversity that were determined using polymorphic markers, developed in chapter four, were used. These results suggested that sexual reproduction is occurring more frequently in the more recently collected populations than in the initial population. Mango malformation is an important disease in mango growing areas. The study presented in chapter six indicated that this disease is associated with two distinct Fusarium spp. in the section Liseola. The two new Fusarium spp. are thus described as F. mangiferae and F. sterilihyphosum using morphological criteria In chapter seven, the distribution and vegetative compatibility of both F. mangiferae and F. sterilihyphosum was determined for the South Africa populations. Results revealed that each of these species differ in their distribution in South Africa. Vegetative compatibility tests also suggest that both species represent single genets in South Africa. Fusarium subglutinans sensu lato isolates associated with pme and mango are economically important fungi. The focus of the studies presented in this thesis has been on the taxonomy and population genetics of these fungi, with special reference to their occurrence in South Africa. Each of the chapters will contributes towards a better understanding of the taxonomy, population genetics and biology of these fungi. / Thesis (PhD)--University of Pretoria, 2006. / Microbiology and Plant Pathology / Unrestricted

Made available in DSpace on 2017-07-25T19:29:57Z (GMT). No. of bitstreams: 1 Monica G Harms.pdf: 1165275 bytes, checksum: cc8059801e06e439fa7ed83ee82ad8db (MD5) Previous issue date: 2013-02-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The ideal plants density consists in an extremely important condition in the determining of yield and in the commercial production of onion bulbs. The producers have sought new spatial distributions of plants, aiming harvest bulbs in accord with the size required by the consumer. The plants population have also influence on the development of diseases, because it is associated with the infective units spread of the pathogen and microclimate in culture. The experiment was conducted in the Capão da Onça School Farm aiming to evaluate the influence of plants density and the fungicide use in the occurrence of foliar diseases and the productive characteristics of Bola Precoce cultivar and Bella Dura hybrid. The experimental design was complete randomized blocks, with four replications for the Bola Precoce cultivar and three replications for the Bella Dura hybrid. The treatments were arranged in a split plot design, where the plots were either the presence or the absence of fungicide (metiram + piraclostrobina - 2,5 kg p.c. ha-1) and plant densities (12, 14, 16, 18, 20 and 22 plants m-1) were the split plots. Parameters evaluated were: severity of downy mildew (Peronospora destructor) and purple blotch (Alternaria porri), number of harvest bulbs, bulb mass, bulb diameter, bulb classification and yield. With the data of severity, the area under disease progress curve (AUDPC) was calculated. For Bola Precoce cultivar, no differences were observed between the densities for the parameters AUDPC (downy mildew and purple blotch), purple blotch severity, bulb mass, bulb diameter and bulbs class 0, 2, 3 and 3C. There was difference between densities for downy mildew severity in the evaluation made at 111 days after transplantation (DAT), and the maximum value (34,65%) was found in 15,3 plants m-1 density, in presence of fungicide. The fungicide was effective on downy mildew control in the evaluation made at 97 DAT and on the purple blotch control in the evaluation made at 97 and 104 DAT. The maximum yield was obtained in 22 plants m-1 density, reaching 18,21 and 17,70 t ha-1 in presence and absence of fungicide, respectively. For Bella Dura hybrid, no differences were observed between densities for AUDPC (downy mildew and purple blotch), bulbs class 0, downy mildew severity at 90, 97 and 104 DAT, and purple blotch severity at 90, 97 and 111 DAT. The fungicide was effective in controlling downy mildew in the evaluations made at 97 and 104 DAT. In absence of fungicide, the yield increased with the plant density increasing. In presence of fungicide, the maximum yield (22,09 t ha-1) was obtained in 17,45 plants m-1 density. There was a reduction of the mass and diameter of bulb with the plant density increment, when no fungicide was applied. In presence of fungicide, the percentage of bulbs class 3C decreased with the plant density increase. / A densidade ideal de plantas é extremamente importante na determinação da produtividade e da produção comercial de bulbos de cebola. Produtores têm buscado novas distribuições espaciais de plantas, objetivando colheita de bulbos de acordo com o tamanho exigido pelo consumidor. A densidade de plantas também influencia o desenvolvimento de doenças, pois tem relação com a disseminação das unidades infectivas do patógeno e o microclima na cultura. O experimento foi conduzido na Fazenda Escola Capão da Onça com o objetivo de avaliar a influência da densidade de plantas e o uso de fungicida na ocorrência de doenças foliares e nas características produtivas do cultivar Bola Precoce e do híbrido Bella Dura. O delineamento experimental utilizado foi o de blocos ao acaso com quatro repetições para o cultivar Bola Precoce e três repetições para o híbrido Bella Dura. Os tratamentos foram arranjados em parcelas subdivididas, sendo que as parcelas constituíram a presença ou ausência de fungicida (metiram + piraclostrobina - 2,5 kg p.c. ha-1) e as densidades de plantas (12, 14, 16, 18, 20 e 22 plantas m-1) constituíram as subparcelas. As características avaliadas foram: severidade de míldio (Peronospora destructor) e de mancha púrpura (Alternaria porri), número de bulbos, massa média do bulbo, diâmetro médio do bulbo, classificação dos bulbos e produtividade total. Com os dados de severidade calculou-se a área abaixo da curva do progresso das doenças (AACPD). Para o cultivar Bola Precoce, não foram observadas diferenças entre as densidades para os parâmetros AACPD (míldio e mancha púrpura), severidade de mancha púrpura, massa média do bulbo, diâmetro do bulbo e bulbos classe 0, 2, 3 e 3C. Houve diferença entre densidades para a severidade do míldio na avaliação realizada aos 111 dias após o transplante (DAT), sendo o maior valor (34,65%) encontrado na densidade de 15,3 plantas m-1 na presença de fungicida. O fungicida foi eficiente no controle do míldio na avaliação realizada aos 97 DAT e no controle da mancha púrpura nas avaliações realizadas aos 97 e 104 DAT. A produtividade total máxima foi obtida na densidade de 22 plantas m-1, alcançando 18,21 e 17,70 t ha-1 na presença e ausência de fungicida, respectivamente. Para o híbrido Bella Dura, não foram observadas diferenças entre as densidades para os parâmetros AACPD (míldio e mancha púrpura), bulbos classe 0, severidade de míldio aos 90, 97 e 104 DAT e severidade de mancha púrpura aos 90, 97 e 111 DAT. O fungicida foi eficiente no controle do míldio nas avaliações realizadas aos 97 e 104 DAT. Na ausência do fungicida a produtividade total aumentou com o incremento da densidade de plantas. Na presença do fungicida, maior produtividade (22,09 t ha-1) foi obtida na densidade de 17,45 plantas m-1. Houve redução da massa média dos bulbos e do diâmetro do bulbo com o incremento da densidade de plantas quando o fungicida não foi aplicado. Na presença do fungicida, a porcentagem de bulbos pertencentes à classe 3C diminuiu com o aumento da densidade de plantas.

Soy constitutes one of the main crops of Brazilian and world agriculture, with important socio-economic role. In Brazil, currently, the soybean cultivars have increased production potential, and advanced technology for the production of grains and seeds. The productive potential of soy is genetically determined, but environmental factors are responsible for limiting the production. Factors such as height, geographic location, soil texture and fertility, sowing date and plant population are essential for the expression of genetic potential. The Precision Farming tools aim to support the rural activities, generating information of spatial and temporal variability that affects crop yields. We can treat differently parts of the same crop, using efficient and sustainable inputs of agricultural production. The aim of this study was to evaluate the soybean plant behavior in different plants population and management zones. Two soybean cultivars were used the NIDERA 6411 and TEC IRGA 6070, with plants population recommended is 31 to 28 plants per square meter, respectively. The plants population used were 25 and 50% for more and for less than recommended, totaling five treatments for each cultivar. The experimental design was completely randomized bifactorial in each management area. The following variables were evaluated: 1000 grain weight, yield, number of pods per plant, number of pods per square meter and plant height. The experiment was conducted in the experimental area of the Colégio Politécnico da UFSM, in 2015, after the recommended planting time, in the period known as off-season. The results of the variables were subjected to analysis of variance and regression and the means compared by Tukey test (p <0.05). In the high and average zones of management the cultivar NIDERA 6144 with plants population of 38 and 42 plants per square meter had the maximum technical efficiency. Already in low productivity zone, farming TEC IRGA 6070, in the amount of 47 plants per square meter, present the maximum technical efficiency. The population of plants inversely impacts the total number of pods per plant and directly the number of pods per square meter. Plant height is directly affected by the population of plants so that the higher the population, higher plant height, desired condition in planting after the recommended period. / A soja constitui-se em um dos principais cultivos da agricultura brasileira e mundial, com relevante papel socioeconômico. No Brasil, atualmente, as cultivares de soja apresentam potencial produtivo cada vez maior, além de tecnologia avançada para a produção de grãos e sementes. O potencial produtivo da soja é determinado geneticamente, porém os fatores ambientais são responsáveis por limitar o teto produtivo. Fatores como altitude, latitude, textura, fertilidade do solo, época de semeadura e população de plantas são fundamentais para a expressão do potencial genético. As ferramentas da agricultura de precisão visam dar suporte às atividades rurais, gerando informações da variabilidade espacial e temporal que afeta a produtividade das culturas. Desta maneira podemos tratar diferenciadamente partes da mesma lavoura, usando de forma eficiente e sustentável os insumos da produção agrícola. O objetivo desse trabalho foi avaliar o comportamento de plantas de soja em diferentes populações e zonas de manejo. Foram utilizadas duas cultivares de soja, a NIDERA 6411 e a TEC IRGA 6070, com populações recomendadas de 31 e 28 plantas por metro quadrado, respectivamente. As populações utilizadas foram de 25 e 50% para mais e para menos do que o recomendado, totalizando cinco tratamentos para cada cultivar. O delineamento foi um bifatorial inteiramente casualizado em cada zona de manejo. Foram avaliadas as seguintes variáveis: peso de 1000 grãos, produtividade, número de legumes por planta, número de legumes por metro quadrado e altura de planta. O experimento foi conduzido em área experimental do Colégio Politécnico da UFSM, no ano de 2015, após a época recomendada de plantio, no período conhecido como safrinha. Os resultados das variáveis foram submetidos à análise de variância e regressão e as médias comparadas pelo Teste de Tukey (p<0,05). Em plantio após época recomendada, as maiores produtividades foram obtidas pelo aumento da população de plantas. Nas zonas de alta e de média produtividade, a cultivar NIDERA 6411, na população de 38 e de 42 plantas m-2, respectivamente, apresentou a máxima eficiência técnica. Já na zona de baixa produtividade, a cultivar TEC IRGA 6070, na população de 47 plantas m-2, apresentou a máxima eficiência técnica. A população de plantas impacta de forma inversa o número total de legumes por planta e de forma direta o número de legumes por metro quadrado. A altura da planta é afetada diretamente pela população de plantas, de forma que quanto maior a população, maior será a altura de plantas, condição desejada no plantio após a época recomendada.

Made available in DSpace on 2016-02-26T12:59:39Z (GMT). No. of bitstreams: 1 ElaineEvaOliveiraMunarin.pdf: 1756719 bytes, checksum: 94d36800ecb3553cd14b84ba444566d4 (MD5) Previous issue date: 2008-03-20 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The experiment was carried out in the medicinal garden of the Universidade Federal da Grande Dourados UFGD, in the period from February to October 2006. The survey aimed to study the growth, development and yield of Bardana responding to five different spacing rows between the plants (40,0; 47,5; 55,0; 62,5 and 70,0 cm) and to the use - CCF (10 t ha-1) or not - SCF - of semi-decomposed poultry litter. All ten experimental designs were arranged in a factorial scheme 5x2 in randomized blocks with four replications. Plants were initially propagated in sowing polystyrene plates and then they were placed in double rows 50 cm far of each other. Harvest was done 180 days after transplanting. Plants averages of height (172 cm) and foliar area (20.704 cm-2) and roots averages of length (23,6 cm) and diameter (16,2 mm) were neither significantly influenced by the spacing nor positively influenced by the use or not of the semi-decomposed poultry litter. Highest and lowest values of leaves fresh (25.676 kg ha-1 and 15.217 kg ha-1) and dry (1.941,02 kg ha-1 e 1.104,61 kg ha-1) masses, of root number (490.750 ha-1 and 272.120 ha-1) and roots fresh (5.080,35 kg ha-1 and 3.546,25 kg ha-1) and dry (1.448,91 kg ha-1 and 1.051,31 kg ha-1) masses were found in 40,0 and 70,0 cm spaces respectively, showing linear decrease as spacing was increased. Dry leaves (12,84 g kg-1 and 0,33 g kg-1) and roots (4,11 g kg-1 and 0,13 g kg-1) mass rates of Nitrogen (N) and Phosphorous (P), respectively, were not significantly influenced by spacing but they were by the covering or not with chicken manure respectively / O experimento foi desenvolvido no Horto de Plantas Medicinais, da Universidade Federal da Grande Dourados - UFGD, no período de fevereiro a outubro de 2006. O objetivo foi estudar o crescimento, o desenvolvimento e a produção da bardana em resposta a cinco espaçamentos entre plantas (40,0; 47,5; 55,0; 62,5 e 70,0 cm) e ao uso - CCF (10 t ha-1) ou não - SCF de cobertura do solo com cama-de-frango semidecomposta. Os dez tratamentos foram arranjados como fatorial 5x2, no delineamento experimental blocos casualizados, com quatro repetições. As plantas foram propagadas inicialmente em berços de isopor e, posteriormente, em canteiros, arranjadas em fileiras duplas, espaçadas de 50 cm entre elas. A colheita foi efetuada aos 180 dias após o transplante. As médias de altura (172 cm) e área foliar (20.704 cm-2) das plantas e as médias de comprimento (23,6 cm) e diâmetro das raízes (16,2 mm) não foram influenciadas significativamente pelos espaçamentos nem pela cobertura ou não do solo com cama-de-frango. Os maiores e menores valores para massas fresca (25.676 kg ha-1 e 15.217 kg ha-1) e seca (1.941,02 kg ha-1 e 1.104,61 kg ha-1) de folhas, para o número de raízes (490.750 ha-1 e 272.120 ha-1) e para as massas fresca (5.080,35 kg ha-1 e 3.546,25 kg ha-1) e seca (1.448,91 kg ha-1 e 1.051,31 kg ha-1) de raízes foram encontrados com os espaçamentos de 40,0 cm e de 70,0 cm entre plantas, respectivamente, mostrando decréscimo linear na medida em que aumentaram os espaçamentos. Os teores de nitrogênio (N) e de fósforo (P), respectivamente, nas massas secas de folhas (12,84 g kg-1 e 0,33 g kg-1) e de raízes (4,11 g kg-1 e 0,13 g kg-1) de bardana não foram influenciados significativamente pelos espaçamentos, mas sim pela cobertura ou não do solo com cama-de-frango respectivamente

Made available in DSpace on 2016-02-26T12:59:19Z (GMT). No. of bitstreams: 1 ElaineEvaOliveiraMunarin.pdf: 1756719 bytes, checksum: 94d36800ecb3553cd14b84ba444566d4 (MD5) Previous issue date: 2008-03-20 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The experiment was carried out in the medicinal garden of the Universidade Federal da Grande Dourados UFGD, in the period from February to October 2006. The survey aimed to study the growth, development and yield of Bardana responding to five different spacing rows between the plants (40,0; 47,5; 55,0; 62,5 and 70,0 cm) and to the use - CCF (10 t ha-1) or not - SCF - of semi-decomposed poultry litter. All ten experimental designs were arranged in a factorial scheme 5x2 in randomized blocks with four replications. Plants were initially propagated in sowing polystyrene plates and then they were placed in double rows 50 cm far of each other. Harvest was done 180 days after transplanting. Plants averages of height (172 cm) and foliar area (20.704 cm-2) and roots averages of length (23,6 cm) and diameter (16,2 mm) were neither significantly influenced by the spacing nor positively influenced by the use or not of the semi-decomposed poultry litter. Highest and lowest values of leaves fresh (25.676 kg ha-1 and 15.217 kg ha-1) and dry (1.941,02 kg ha-1 e 1.104,61 kg ha-1) masses, of root number (490.750 ha-1 and 272.120 ha-1) and roots fresh (5.080,35 kg ha-1 and 3.546,25 kg ha-1) and dry (1.448,91 kg ha-1 and 1.051,31 kg ha-1) masses were found in 40,0 and 70,0 cm spaces respectively, showing linear decrease as spacing was increased. Dry leaves (12,84 g kg-1 and 0,33 g kg-1) and roots (4,11 g kg-1 and 0,13 g kg-1) mass rates of Nitrogen (N) and Phosphorous (P), respectively, were not significantly influenced by spacing but they were by the covering or not with chicken manure respectively / O experimento foi desenvolvido no Horto de Plantas Medicinais, da Universidade Federal da Grande Dourados - UFGD, no período de fevereiro a outubro de 2006. O objetivo foi estudar o crescimento, o desenvolvimento e a produção da bardana em resposta a cinco espaçamentos entre plantas (40,0; 47,5; 55,0; 62,5 e 70,0 cm) e ao uso - CCF (10 t ha-1) ou não - SCF de cobertura do solo com cama-de-frango semidecomposta. Os dez tratamentos foram arranjados como fatorial 5x2, no delineamento experimental blocos casualizados, com quatro repetições. As plantas foram propagadas inicialmente em berços de isopor e, posteriormente, em canteiros, arranjadas em fileiras duplas, espaçadas de 50 cm entre elas. A colheita foi efetuada aos 180 dias após o transplante. As médias de altura (172 cm) e área foliar (20.704 cm-2) das plantas e as médias de comprimento (23,6 cm) e diâmetro das raízes (16,2 mm) não foram influenciadas significativamente pelos espaçamentos nem pela cobertura ou não do solo com cama-de-frango. Os maiores e menores valores para massas fresca (25.676 kg ha-1 e 15.217 kg ha-1) e seca (1.941,02 kg ha-1 e 1.104,61 kg ha-1) de folhas, para o número de raízes (490.750 ha-1 e 272.120 ha-1) e para as massas fresca (5.080,35 kg ha-1 e 3.546,25 kg ha-1) e seca (1.448,91 kg ha-1 e 1.051,31 kg ha-1) de raízes foram encontrados com os espaçamentos de 40,0 cm e de 70,0 cm entre plantas, respectivamente, mostrando decréscimo linear na medida em que aumentaram os espaçamentos. Os teores de nitrogênio (N) e de fósforo (P), respectivamente, nas massas secas de folhas (12,84 g kg-1 e 0,33 g kg-1) e de raízes (4,11 g kg-1 e 0,13 g kg-1) de bardana não foram influenciados significativamente pelos espaçamentos, mas sim pela cobertura ou não do solo com cama-de-frango respectivamente

To assess the status of a rare plant species, we must first understand the factors that affect the size of populations and their numbers. In this thesis, I study processes affecting plant species prosperity on local scale (paper 1), factors influencing species distribution in landscape and ability of species to colonize new habitats (paper 2) and species traits responsible for gene flow between established populations (paper 3). Since I work with rare plants, I also aim to turn theoretical knowledge into practical recommendations for nature conservation (paper 4) to help effectively preserve rare and endangered species. In the first 3 papers, I work with two rare fern species restricted to serpentine rocks, Asplenium adulterinum and A. cuneifolium, in a study system covering 10 × 10 km. I found that both species are long living (several decades) and in the study region, populations are in a good state and slowly growing. Even very small populations (10 individuals) have quite high chance to survive. In both fern species, I found dispersal limitation, which might be surprising regarding huge production of small spores in ferns (paper 2). The species differ in ploidy and thus, also mating system. A. adulterinum is tetraploid and its main breeding system is intragametophytic selfing. A. cuneifolium is...

Submitted by Neusa Fagundes (neusa.fagundes@unioeste.br) on 2017-09-21T18:50:58Z No. of bitstreams: 1 Marcus_Machado2017.pdf: 1121735 bytes, checksum: 9ea84f769f344f4ca6f35da15bcea609 (MD5) / Made available in DSpace on 2017-09-21T18:50:58Z (GMT). No. of bitstreams: 1 Marcus_Machado2017.pdf: 1121735 bytes, checksum: 9ea84f769f344f4ca6f35da15bcea609 (MD5) Previous issue date: 2017-02-13 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Precision agriculture is essential for farmers who want to increase their productivity and reduce costs with agricultural inputs. One way of using precision agriculture is to divide the area used for cultivation into individualized plots with similar productive potentials within the plot and different among plots; these fractions of the total area are called Management Units (MUs). In this context, the objective of the study was to verify the effectiveness of the division of the area in MUs and to define the plant density for the soybean crop that provides greater productive efficiency in each MU in an experimental area with 15.5 ha, located in Céu Azul City, Paraná State, in Brazil. In the experiment, the formation of the MUs occurred following the steps: collection of soil samples to characterize the chemical and physical attributes; selection of attributes with higher correlation with productivity; interpolation and generation of thematic maps with the values of the attributes selected in the sample points; grouping of data and definition of MUs, considering that the entire computational process was performed with the help of the Software for the Definition of Management Units (SDUM). For the formation of MUs, it was used the attributes of altitude and soil penetration resistance 0-0.1m, attributes that have a greater spatial correlation with productivity in the field. The area was divided into 2 MUs, 4 contour lines (CLs) and 16 plots. In the field, 2 plant densities were applied, 214,000 and 257,000 plants ha-1, and each density was applied in 8 different plots, using line spacing of 0.70 m. In order to characterize and quantify differences in MUs and CLs and the efficiency of plant densities in the MUs, the productivity was measured at 37 points in each plot. Regarding productivity, it was found that there was a significant difference at the level of 5% between MUs, being that the MU with greater productive potential, located in the highest part in the area, achieved higher productivity; the application of the two different plant densities in the MUs generated effect, being that the densities of 214,000 and 257,000 plants ha-1 reached, respectively, higher productivity in MU2 and MU1; also, there was a difference in productivity between CLs. / A agricultura de precisão é essencial para produtores que desejam aumentar sua produtividade e reduzir custos com insumos agrícolas. Uma forma de se utilizar a agricultura de precisão é dividindo-se a área utilizada para cultivo em parcelas individualizadas, com potenciais produtivos semelhantes dentro da parcela e diferentes entre parcelas; essas frações da área total são chamadas de Unidades de Manejo (UMs). Nesse contexto, o objetivo do trabalho foi constatar a efetividade da divisão da área em UMs e definir a densidade de plantas para o cultivo de soja que proporcione maior eficiência produtiva em cada UM em área experimental com 15,5 ha, localizada em Céu Azul/PR. No experimento, a formação das UMs ocorreu seguindo-se as etapas: coleta de amostras de solo para caracterizar os atributos químicos e físicos; seleção de atributos com maior correlação com a produtividade; interpolação e geração de mapas temáticos com os valores dos atributos selecionados nos pontos amostrados; agrupamento de dados e definição de UMs, sendo que todo o processo computacional foi realizado com o auxílio do Software para Definição de Unidades de Manejo (SDUM). Para formação das UMs utilizou-se dos atributos altitude e a resistência a penetração do solo 0-0,1 m, que possuem maior correlação espacial com a produtividade no local trabalhado. A área foi dividida em 2 UMs, 4 curvas de nível (CNs) e 16 parcelas. Aplicou-se no plantio 2 densidades de plantas, 214.000 e 257.000 plantas ha-1, sendo que cada densidade foi aplicada em 8 parcelas diferentes, utilizando o espaçamento entre linhas de 0,70 m. Para caracterizar e quantificar diferenças nas UMs e nas CNs e a eficiência das densidades de plantas nas UMs, a produtividade foi medida em 37 pontos em cada parcela. Constatou-se em relação à produtividade que houve diferença significativa ao nível de 5% entre UMs, sendo que a UM com maior potencial produtivo, localizada na parte mais elevada na área, alcançou maior produtividade. Houve efeito na aplicação das duas diferentes densidades de plantas nas UMs, sendo que as densidades de 214.000 e 257.000 plantas ha-1 alcançaram, respectivamente, produtividade superior na UM2 e na UM1; além disso, existiu diferença na produtividade entre as CNs.

Increased temperatures due to anthropogenic-induced climate change may raise the threat of extinction for taxa with sessile life histories (e.g., plants) in the near future. Linking climate change models to demographic models may provide useful insights into the potential effects of environmental changes on rare plants, and therefore aid in their current and future conservation. Population demographers generally agree that mechanistic models from a reductionist perspective are necessary to test assumptions in population drivers. For the first study, I assessed the climate vulnerability of a rare plant species, Pyrrocoma radiata, with a mechanistic model of four climatically-similar populations. I used environmentally-driven demographic models to estimate vital rates and population sizes from a nonlinear, nonparametric regression with local climate variables. I assessed the utility of this environmentally-correlated, stage-structured population matrix model compared to a stationary model of independent and identically-distributed environmental stochasticity. I then simulated future population projections based on climate conditions predicted by General Circulation Models (GCMs) under opposing emission scenarios. The second study hopes to answer population-level questions using a traditionally community-level method, non-metric multidimensional scaling, which considers correlation structure between response variables and can be used to find environmental correlates of the ordination axes. Demographic data on a threatened perennial, Astragalus tyghensis, were collected from five sites in the Tygh Valley, OR. I considered correlation structure between demographic vital rates to find environmental correlates of the ordination axes. The search for an environmental driver of population vital rates was successful for the two study species. Previous year dry dormant season precipitation likely affects the fertility rates a year later in P. radiata populations, and dry growing season reference evapotranspiration rates positively correlated with a growth gradient in A. tyghensis. Based on predicted precipitation, P. radiata is expected to rapidly decline by 2050, but this may be due to biases in the two GCMs and reliance on only one environmental factor. The NMS ordination adequately captured most of the variation in transition elements for the years and populations from A. tyghensis demographics. I provided support to the claim that model predictions can improve with the inclusion of mechanistic relationships. The inclusion of abiotic drivers in models used to predict population trends is supported by our study and may enhance predictive power in population viability assessments under changing climates. / Graduation date: 2013