Made available in DSpace on 2014-06-11T19:30:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-06-20Bitstream added on 2014-06-13T20:01:15Z : No. of bitstreams: 1 socolowski_f_dr_rcla.pdf: 774673 bytes, checksum: 524e3b5dcb3693c8da59453eb583ea90 (MD5) / Este estudo teve como objetivo avaliar a relação entre a massa e características morfométricas de frutos e sementes de Tecoma stans, bem como relacionar a massa das sementes a suas características morfológicas, utilizando paquímetro e imagens de raios X, e fisiológicas, através da germinação, emergência e desenvolvimento inicial de suas plântulas, sob duas condições de luminosidade . a pleno sol e sombra. Além disso, também foram avaliados os efeitos de diferentes condições de temperatura e luz constantes, em laboratório, e em ambiente natural no sol e na sombra na germinação e emergência das plântulas. A massa dos frutos apresentou relações lineares significativas e positivas com suas características morfológicas e de produção de sementes. As relações entre a massa das sementes e suas características morfológicas foram positivas e significativas, porém na forma de uma função potência, sendo esta relação mais evidente com a largura do embrião. A massa das sementes também esteve relacionada a determinadas anomalias do desenvolvimento embrionário, observadas nas imagens de raios X. A germinação, a emergência e o desenvolvimento inicial das plântulas foram significativamente afetados pela massa das sementes, porém somente durante os três primeiros meses de desenvolvimento no ambiente de sol. A temperatura apresentou efeito na germinação e suas sementes germinaram tanto na luz quanto no escuro, contudo a emergência e sobrevivência das plântulas no ambiente de sol foi superior em relação ao observado na sombra. / This study had the objective to evaluate the relationship between the mass and the morphometric characteristics of Tecoma stans fruits and seeds, as well as to relate the seed mass with its morphometric characteristics, utilizing caliper and X-ray images, and physiological characteristics, thought germination, emergency and seedlings initial development, under two conditions of light - at the sun and shade. More than, also were evaluated the effects of different conditions of constant temperature and light, under laboratory, and natural environment under sun and shade in the germination and emergency of the seedlings. The fruit mass presented positive, significative linear relationship with his morphological characteristics and with its seed production characteristics. The relationship between seed mass and its morphological characteristics were positive and significative, nevertheless with the model (shape) of power function, being the relationship more clear with the embryo width. The seed mass also was related to determinate anomalies of the embryo development that could be observed in the X-ray images. The germination, the seedling emergence and the initial seedling development were significative affected by seed mass, but only in the firth three months of development at the sun environment. The temperature affected Tecoma stans seed germination in both light and darkness environment, however the seedlings emergency and survival was greater at the sun environment than shade.

Este trabalho foi realizado com o objetivo de avaliar a influência do volume e da granulometria do substrato comercial, utilizado na produção de mudas em tubetes, sobre o crescimento vegetativo das plantas de café, bem como o tempo de formação das mudas e a estabilidade ao manuseio do conjunto muda-substrato. O experimento foi conduzido no viveiro do Centro de Café do IAC, localizado na Fazenda Santa Elisa, Campinas, SP, utilizando a cultivar Catuaí Vermelho IAC 144 (Coffea arabica L.). Foram adotados nove tratamentos com quatro repetições, com delineamento de blocos ao acaso em esquema fatorial 3 x 3, formado pela combinação de três volumes de substrato (50, 120 e 200 cm3) e três granulometrias proporcionadas pelas seguintes composições granulométricas: 100% de substrato comercial na granulometria original, 100% de substrato comercial finamente moído e pela mistura, em volume, de 50% de substrato na granulometria comercial com 50% de substrato moído. A influência das variáveis (volume e granulometria) do substrato no crescimento das mudas de café foi avaliada por meio das determinações dos parâmetros biométricos vegetativo da parte aérea e raízes como: número de pares de folhas, altura da planta, diâmetro do caule, matéria seca da parte aérea e das raízes, área foliar total, área foliar média, área do 1o par de folhas, comprimento e superfície de raízes. Em complemento aos objetivos do trabalho foram, também, avaliados o tempo de formação das mudas e a estabilidade ao manuseio do conjunto muda-substrato. O crescimento das plantas depende do volume e da granulometria do substrato, sendo maior com a utilização de 200 cm3 de substrato e a diminuição da granulometria pela mistura, em partes iguais, do substrato finamente moído com o substrato comercial na granulometria original. O tempo de formação das mudas correlacionou com o volume de substrato, demandando 134, 124 e 81 dias para a emissão do 4o par de folhas, quando as plantas cresceram nos recipientes com 50, 120 e 200 cm3 de substrato, respectivamente. A estabilidade ao manuseio do conjunto mudasubstrato varia com o tamanho do recipiente, sendo maior nos tubetes com 50 e 120 cm3 de substrato, e a redução parcial da granulometria, pela mistura granulométrica, aumentou a aderência das partículas com as raízes e, portanto, a estabilidade do conjunto. / The objectives of this research are the evaluation of substrate volume and granulometer influence - used in production of coffee seedlings in plastic tubes - on coffee plants growth, the time of seedlings development and also seedling-substrate handling stability. The investigation was carried out in a nursery at Coffee Experimental Center of IAC, SP, Brazil, with the cultivar Catuaí Vermelho IAC 144 (Coffea arabica L.). Nine treatments were tested with 4 replicates and the experimental design used was randomized blocks with 3x3 factorial composed by 3 substrate volumes (50, 120 and 200 cm3) and 3 granulometer substrate levels obtained by the following granulometer compositions: 100% of substrate on original granulometer, 100% of crushed substrate and the mix, in volume, of 50% of substrate on original granulometer and 50% of crushed substrate. The substrate volume and granulometer influence on coffee seedlings growth was evaluated by determination of growth parameters of shoot and root as: number of leaves, seedling height, stem diameter, root and shoot dry matter, total leaf area, average leaf area, first leaf area, root length and surface. In addition to these parameters, the time of seedlings development and seedling-substrate handling stability were also investigated. The seedlings growth depend on substrate volume and granulometer, being higher when 200 cm3 of substrate volume are used keeping an equal proportion of the different substrate granulometers (original and crushed). The time of seedlings growth did show a correlation with the substrate volume demanding 134, 124 and 81 days for developing the 4th leaf pair when the plants developed in 50, 120 and 200 cm3 of substrate, respectivelly. The seedling-substrate handling stability differs with recipient size, while the granulometer reduction increases the seedling-substrate stability.

Made available in DSpace on 2017-07-10T17:37:35Z (GMT). No. of bitstreams: 1 Noelle_Farias_Aquino.pdf: 377139 bytes, checksum: 4b46af9081e8e4b3493e8cee5428bcf4 (MD5) Previous issue date: 2009-08-08 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The objective of this work was to identify differences in the development of Jatropha curcas from three origins and the influence of mycorrhizal fungi. Physic-nut seedlings were produced in the Municipality of Marechal Cândi Rondon PR and by the age of 60 days they were allocated in plastic vase with a capacity of 18 L. The vases were filled with three types of soil, control (no treatment), solarized and solarized with inoculum of mycorrhizal fungi. At 60 days after sowing, morphometric and destructive analysis were performed to determine fresh and dried masses. Throughout the period of the experiment there was gathering of morphometric data in order to determine the development of seedlings. At 60 days it was possible to note there are differences in the formation of seedlings between seeds from different provenances. Among the evaluated provenances, Mato Grosso do Sul showed higher averages for almost all evaluated parameters, except for number of leaves (NF), which the highest average was for the seedling from Minas Gerais. Seedlings produced with seeds from Pernambuco showed lower values in all variables measured, including the ratio between height and collar diameter (H: DC). The differences between the studied origins persisted after planting the seedlings in vases. As to soil treatments, the presence of mycorrhizal fungi in roots influenced the development, and its absence was not favorable to the development of seedlings, showing the same behavior throughout trial and for most variables / O objetivo deste trabalho foi avaliar o desenvolvimento de mudas de Jatropha curcas provenientes de três procedências e verificar a influência de fungos micorrízicos. Para tanto mudas de pinhão manso foram produzidas no Município de Marechal Cândido Rondon - PR, e aos 60 dias essas foram alocadas em vasos plásticos com capacidade de 18 L. Os vasos foram preenchidos com três tipos de solo, testemunha (sem tratamento), solarizado e solarizado com inóculo de fungos micorrizos. Aos 60 dias da semeadura realizou-se análise morfométrica e destrutiva de massas frescas e secas. Durante todo o período do experimento houve coleta de dados morfométricos para determinação do desenvolvimento das mudas. Aos 60 dias pode-se notar existência de diferenças no crescimento de mudas a partir de sementes provenientes de diferentes regiões. Entre as procedências avaliadas, a procedência Mato Grosso do Sul mostrou médias superiores em quase todos os parâmetros avaliados, com exceção de número de folhas (NF), cujo maior média foi obtida em mudas da procedência Minas Gerais. Mudas formadas com sementes da procedência Pernambuco apresentaram menores valores em todas as variáveis mensuradas, inclusive para a razão entre altura e diâmetro de coleto (H:DC). As diferenças entre as procedências persistiram após o plantio das mudas em vasos estudadas. Quanto aos tratamentos de solo, a presença de fungos micorrizos nas raízes influenciou o desenvolvimento, sendo a sua ausência desfavorável ao desenvolvimento das mudas, apresentando o mesmo comportamento durante todo experimento e para a maioria das variáveis estudadas

Native plant materials are often seeded to restore biodiversity and ecosystem function in areas overtaken by exotic weeds. Plant materials are evaluated on intraspecific differences in productivity and expression of traits advantageous to establishment (e.g., phenology, seed mass, and growth rate); some investigations also consider population-level adaptation to exotic species. However, there is a lack of studies that broadly evaluate response to competition from exotic species at multiple scales within a species. In a greenhouse experiment, we used analysis of variance to assess the growth response of a perennial grass native to the Intermountain West, (Elymus elymoides), to competition from a common invasive species, (Bromus tectorum), at three levels of intraspecific differentiation: subspecies, lineage (wild vs. domestic germplasm), and population. We used regression analysis to assess whether E. elymoides populations from highly invaded areas were less affected by B. tectorum competition. Finally, we explored the relationship between growth traits and competitive response using random forest regression. We found significant differences among E. elymoides subspecies in their response to B. tectorum competition, no difference between wild and domestic lineages, and no population-level differentiation within subspecies. Field abundance of B. tectorum had a significant positive relationship with E. elymoides biomass, but not competitive response, suggesting that E. elymoides has not adapted to the invader. Elymus elymoides plants which were less affected by competition were smaller, allocated more biomass to leaves, and had fewer fine roots, suggesting that light interception and tissue retention were prioritized by seedlings in this competitive greenhouse environment.

acase@tulane.edu

A study of the microclimate of erosion control treatments was carried out in two habitat types in a semiarid southeastern Utah, salt desert shrub area. The soils are highly eroded Mancos shale and support a low density of salt desert shrub species which offers little protection against high intensity summer convectional rainstorms. Gully plugs and contour furrows had been installed by the Bureaus of Reclamation and Land Management to prevent runoff of soil laden water which results from these summer rainfalls. Formerly this sediment was carried to the Colorado River and deposited in Lake Powell. The purpose to t he study was to measure some parameters that influenced establishment and survival of seedlings which would stabilize the structures and increase the productivity of the area. Mature, indigenous species close to the structures had greater vigor and provided a larger, more constant seed source. This seed source was important since original seedlings of introduced grasses have failed to establish and stabilize the structures . Following favorable late winter and early spring precipitation, high numbers of seedlings emerged, but few survived into mid-summer. Those that did survive were found only at or near the high water line of the gully plugs and in the bottom of contour furrows. To aid in the explanation of the differential seedling survival, soil surface moisture following rainstorms, physical and chemical soil characteristics, net radiation, soil surface temperature, and evaporation were investigated. Sampling of the 15 centimeter soil surface in the environs of the structures showed that two days after either heavy or light rainfalls, essentially no available water remained on the sloping throw positions of the structures. The bottom of the gully plugs remained flooded for several days. As a result, the seedlings were drowned. Only at the high water line of the gully plugs and in the bottom of furrows was there enough water to support seedling growth in summer. Runoff water from summer storms carried fine material into the structures, which covered and destroyed seedlings, plus lowered infiltration and permitted much of the water to be lost through evaporation. The runoff water also carried salts brought to the surface by the desert shrubs or by the upward movement of water during evaporation from the soil surface. Sampling of soil in the environs of the structures showed no substantial build up of salt, indicating that leaching had occurred, or still was occurring. This does not mean that a build up will not result in the future. Seasonal salt distribution showed that lowest salinity levels did not always coincide with springtime when seedlings generally emerged. Established seedlings were also exposed to a harsh environment of high soil surface temperatures (over 60 C) and high soil water evaporation rates that were detrimental to their survival. In summary, the study showed that the erosion control structures have created a microenvironment much different from the undisturbed soil, which only permits the establishment of species with much different tolerances from the indigenous species.

This study examined the effects of seedbed and seedling environment on establishment of early and late seral dominant alpine species. Species studied included late seral dominant forbs (Geum rossii, Artemisia scopulorum, and Polemonium viscosum), early seral dominant forbs (Potentilla diversifolia and Sibbaldia procumbens), a late seral dominant grass (Festuca idahoensis), and early seral dominant grasses (Calamagrostis purpurascens and Deschampsia cespitosa). Germination responses of each species to wet vs. dry cold stratification and light vs. dark conditions were investigated. No statistical differences were observed in the seed germination of early and late seral dominant forbs or early and late seral dominant grasses, but significant differences were observed in the responses of grasses and forbs. Seed germination of forbs was greater under light than dark conditions and following wet cold storage. Effects of fertilization on growth responses and nutrient uptake of G. rossii and D. cespitosawere evaluated in a factorial greenhouse experiment in which seedlings of each species were grown at four levels of nitrogen (N) and phosphorous (P). The late seral dominant forb responded more like a species from a low-nutrient environment exhibiting lower relative growth rates, higher root:shoot ratios, and a smaller response to N than the early seral dominant. A field experiment on the Beartooth Plateau, Montana, examined the soil environment and seedling emergence, growth, and survival of seeded early and late seral dominants on loamy sand soils of a severe disturbance and on peat soils of an undisturbed area during two growing seasons. Effects of fertilizer and mulch were examined on the severely disturbed area. Differences between uncleared turf and turf cleared of vegetation (gap disturbance) were evaluated on the undisturbed area. The gap disturbance had higher levels of N and P and warmer soil than the severe disturbance or vegetated undisturbed area. Soil water potentials were never low enough to result in plant stress. Seedling growth was slow - .005 g to .04 g dry weight the first growing season and .02 g to .20 g the second growing season. Growth was greatest on the gap disturbance and on fertilized plots of the severely disturbed area. Early seral dominants had the largest seedlings and the smallest R/R+S ratios. Mortality was low - odds of .50 were rarely exceeded even after two years. Survival was higher on warm, nutrient rich soils of the gap disturbance. Mulch increased emergence and survival on the severe disturbance. Fertilization increased mortality, probably because an initial pulse of N was followed by a rapid decline. Higher mortality occurred in 1986 than 1985 as 1986 had a shorter growing season and cooler air and soil temperatures early in the growing season.

The establishment of alfalfa is expensive and good initial stands permit the farmer to secure high yields and spread establishment costs over several years, Of the factors involved: seedbed preparation, fertilization, seed viability, method of planting, and water application are controlled by the farmer, On the other hand, beneficial and detrimental microflora are not so easily controlled because practices aimed at controlling the detrimental microflora may also destroy the beneficial.

Astragalus lentiginosus, which consists of 36 varieties, is one of the principal locoweeds of western North America. The objectives of this study included identification of some of the major factors affecting germination of the seed and survival of the newly established seedlings for several of these varieties. The seeds of the varieties studied exhibited two mechanisms for dormancy. One is a seed coat that is impermeable to water, and the other is a water-leachable inhibitor. The presence or absence of low-intensity incandescent light (in 14-hour day lengths) had no effect on germination. Of three temperature regimes studied, the regime 7/13 C proved optimal for both total and rapid rate of germination. However, though germinating at lower rates, weeds at -1/4 C and 21/27 C both ultimately reached high percentages of germination. Germination decreased linearly with increasing salinity to almost zero in NaCl solutions of -8.52 bars water potential. Variety araenosus, collected in a salt desert shrub vegetation type showed the highest germination at low temperatures and the greatest salinity tolerance. Seedling survival work was done with both pre-established and established seedlings at the cotyledon to five leaflet stages of development. Seedlings were considered pre-established from the time of germination until the cotyledons were completely unfolded. Afterwards, the seedlings were considered established. Germination and survival of pre-established seedlings were inhibited by day temperatures of 21 C under laboratory conditions. Maximum emergence and survival occurred at the low temperature regime of 4/13 C. However, seedlings of the three to five leaflet stages grew best at day temperatures of 30 C; growth was substantially lower at lower temperatures. Seedlings of var. araenosus displayed the most rapid rate of root growth at 7/12 C while roots of var. vitreus grew at a rate nearly 50 percent lower.

Quaking aspen (Populus tremuloides) is an important species ecologically and culturally in the western U.S., where it is one of the only broadleaf trees in the mostly conifer-dominated forests. Aspen management in the West has focused on regenerating existing stands vegetatively through root suckering, however this approach is restricted to locations where aspen currently exists and limits the genetic diversity of aspen populations. Planting nursery-grown aspen seedlings offers a potential method for overcoming these limitations, but it has received little attention in the U.S. Intermountain West (IW) to date. In order for this approach to be more broadly implemented, nursery protocols designed to grow high-quality aspen seedlings are needed, along with an understanding of what the major challenges to seedling establishment will be. With the assistance of my committee, my research tested a seedling-based approach to aspen restoration in an IW context in two phases. I first used nursery protocols developed for boreal aspen to grow seedlings collected from IW sources in order to assess whether modification of the protocols would be necessary. I then planted the seedlings I grew at three sites in southwestern Utah and monitored their growth and survival over two years. Results from the nursery phase suggest that protocols will need to be modified in order to produce a more consistent response from IW aspen seedlings. In the field, only 10% of the seedlings survived, though the majority of survival occurred in just two locations where soil moisture remained highest during the driest part of the early summer. These results provide useful information to direct future research and suggest that with a better understanding of appropriate site selection, seedling-based aspen restoration could still become a viable management tool in the IW.