Influence of Habitat on the Reproductive Ecology of the Amazonian Palm, Mauritia flexuosa, in Roraima, Brazil

Although Mauritia flexuosa (Arecaceae) plays a pivotal role in the ecology and economy of the Amazon, and occurs in a variety of habitats, little is known about the influence of habitat on the reproductive biology of this palm. My dissertation focuses on the reproductive biology of M. flexuosa in three habitats in Roraima, Brazil: undisturbed forest, undisturbed forest-savanna ecotone, and savanna disturbed by plantations of the exotic tree, Acacia mangium. First, I calculated sex ratios and linked precipitation patterns with phenology. Sex ratios were female-biased. Precipitation was negatively associated with flowering, and positively associated with fruiting. Habitat appears to have no significant influence on phenology of M. flexuosa, although short-term climate variation may affect phenology of this species. Second, I examined floral biology, observed floral visitors, and performed exclusion experiments to determine the pollination system of M. flexuosa. Fruit set did not differ significantly between the visitor exclusion treatment and the control, but was significantly lowest in the wind + visitor exclusion treatment, suggesting that this dioecious palm is anemophilous, independent of habitat. Third, I identified the abiotic and biotic factors explaining variation in fruit mass, seed mass, seed number per fruit, and total fruit yield among habitats. Soil moisture and flooding during the wet season were the best predictors of fruit and seed output. The number of leaves, diameter at breast height, and height were all accurate predictors of reproductive output, but crown volume did not accurately predict fruit yields. Results re-evaluate traditional assumptions about wind-pollination in the tropics, and highlight abiotic and biotic factors responsible for variation in reproductive output of M. flexuosa, with implications for effective management of this palm. Finally, I interviewed harvesters and vendors to document the traditional knowledge and market dynamics of the fruit of M. flexuosa, buriti. Traditional knowledge corroborated results from scientific studies. Vendors argued that the price of buriti must increase, and must fluctuate with varying supply. With appropriate economic incentives to vendors/harvesters, Roraima may expand its market infrastructure for buriti, effectively stimulating the regional economy and practicing sustainable harvesting.

Reducing the number of questions in nonlocal games

We show how a vector-valued version of Schechtmans empirical method can be used to reduce the number of questions in a nonlocal game G while preserving the quotient β*(G)/β(G) of the quantum over the classical bias. We apply our method to the Khot-Vishnoi game, with exponentially many questions per player, to produce a family of games indexed in n with polynomially many (N ≈ n8) questions and n answers per player so that the ratio of the quantum over the classical bias is Ω(n/log2 n).

Effects of plant density and the number of emitters on plant growth and nitrate concentration in spinach cultivated in substrate

The effects of plant density and the number of emitters per Styrofoam box on plant growth and nitrate (NO3-) concentration were evaluated in spinach (Spinacia oleracea L. cv. Tapir). Spinach seedlings were transplanted at 45 days after emergence into Styrofoam boxes filled with the substrate and were grown during winter in an unheated greenhouse with no supplemental lighting. The experiment was carried out with four treatments, including two plant densities (160 and 280 plants/m2) and two number of emitters per Styrofoam box (4 and 8 emitters). Each planting box was irrigated daily and fertigated with a complete nutrient solution. Shoot dry weight was not affected by plant density. However, yield increased with plant density and emitter number. Leaf-blade NO3- concentration was not affected by the interaction between plant density and number of emitters, but petioles NO3- concentration was greater in treatment with 160 plants/m2 and 8 emitters. Although leaf-blade NO3- concentration was not affected by plant density, it decreased with the number of emitters. On the other hand, petiole NO3- concentration was not affected by plant density or number of emitters. Leaf-blade NO3- concentration ranged from 3.2 to 4.1 mg/g fresh weight, occurring the highest value in the treatment with 280 plants/m2 and 4 emitters. Petiole NO3- concentration ranged from 3.5 to 5.3 mg/g fresh weight, values that were higher than allowed by EU regulation.

Methodology to determine the number of infection points of Gibberella zeae in wheat spikes.

2016

The Effect of Coconut Oil and Hibiscus Rosasinensis on Ration Degradability and Number of Protozoa

Concentrated diet based on rice bran 69%, coconut meal 30%, urea 1% and field grass (fg), parsial defaunation agent Hibiscus rosasinensis (Hr) and coconut oil (Co) was used in propotion 37,5% fg + 2,5% Hr; 35% fg + 5% Hr; 37,5% fg + 2,5% Co and 35% + 5% Co. the feed of concentrate and feed grass 60 : 40 % are evaluated in vitro for dry matter degradability (DMD), organic matter degradability (OMD) and number of protozoa (NP). Variance analysis and orthogonal contrast was applied according to Steel and Torrie (1981). The result show that defaunation agent Hr and Co 2,5% and 5% increased (P< 0.01) DMD in the order 60.20; 59.40; 56.60 and 55.60 respectively, compare with no defaunation agent (54,60%). It also increased OMD 62.20%; 60.40; 58.40 and 57.20% compare with no agent (56.40%). While number of protozoa decreased (P< 0.01) 2.456; 2.316; 2.396 and 2.286 x 104/ml rumen liquid compare with no defaunation agent (2.564 x 104/ml rumen liquid). (Animal Production 2(2): 53-59 (2000) Key words : Hibiscus rosasinensis, digestibility, and number of protozoa

Shoot growth dynamics and photosynthetic response to increased nitrogen availability in the alpine willow salix-glauca

Plants subjected to increases in the supply of resource(s) limiting growth may allocate more of those resources to existing leaves, increasing photosynthetic capacity, and/or to production of more leaves, increasing whole-plant photosynthesis. The responses of three populations of the alpine willow, Salix glauca, growing along an alpine topographic sequence representing a gradient in soil moisture and organic matter, and thus potential N supply, to N amendments, were measured over two growing seasons, to elucidate patterns of leaf versus shoot photosynthetic responses. Leaf-(foliar N, photosynthesis rates, photosynthetic N-use efficiency) and shoot-(leaf area per shoot, number of leaves per shoot, stem weight, N resorption efficiency) level measurements were made to examine the spatial and temporal variation in these potential responses to increased N availability. The predominant response of the willows to N fertilization was at the shoot-level, by production of greater leaf area per shoot. Greater leaf area occurred due to production of larger leaves in both years of the experiment and to production of more leaves during the second year of fertilization treatment. Significant leaf-level photosynthetic response occurred only during the first year of treatment, and only in the dry meadow population. Variation in photosynthesis rates was related more to variation in stomatal conductance than to foliar N concentration. Stomatal conductance in turn was significantly related to N fertilization. Differences among the populations in photosynthesis, foliar N, leaf production, and responses to N fertilization indicate N availability may be lowest in the dry meadow population, and highest in the ridge population. This result is contrary to the hypothesis that a gradient of plant available N corresponds with a snowpack/topographic gradient.

Evaluación de la eficacia de la técnica de floating system para la producción de radicchio rosso var. di Verona en condiciones controladas

La técnica de producción en Floating system constituye una alternativa económica y veloz de producción en hidroponia. Este sistema permite obtener hojas de vegetales de pequeño tamaño “Baby leaf” listas para consumir (IV Gama), cuyo consumo a nivel mundial muestra una tendencia creciente. Dicha técnica no se encuentra aún muy difundida para la producción de radicchio rosso. El objetivo de este trabajo fue evaluar el efecto del tamaño de celda, del substrato y de la técnica de floating system sobre la producción de radicchio. Los ensayos se realizaron en cámara a 25 ºC con un fotoperíodo de 16 hs de luz y 8 de oscuridad y con una intensidad de luz de 10 000 Lux. Se utilizó un diseño experimental factorial totalmente aleatorizado, con 5 repeticiones y 3 factores, cuyos niveles fueron: 1) Tamaño de celda, (T), con 3 niveles: grande, mediano y pequeño, 2) Técnica de producción, (F), con 2 niveles: floating system y sistema convencional, 3) Sustrato, (S), con 2 niveles: vermiculita y mezcla. Se analizaron las siguientes variables: 1) peso fresco, 2) peso seco, 3) largo de planta, 4) número de hojas y 5) área foliar. Los resultados obtenidos resultan alentadores respecto del empleo de la técnica de floating system. Para la obtención de plántulas con calidad de IV Gama resulta más conveniente el empleo de celdas de 80 cm3 y sustrato mezcla.

Contribution à l'étude de la croissance de la fougère aquatique Salvinia molesta (Mitchell), Salviniaceae

The growth of the primary and the tertiary forms of the water fern Salvinia molesta was studied during 60 days in 0.06 m2 glass containers containing fresh water. The growth of this plant as a function of time is exponential. The two forms have growth rates statistically identical. The main daily growth rate, expressed in number of leaves, is equal to 6.40% per day for primary forms and 5.90% per day for tertiary form, with doubling time of 10.78 + 1.08 days and 11.64 + 0.15 days.

Corn (Zea mays L.) cultivars tolerance to nicosulfuron

The effects of nicosulfuron on morphological, yield and growth characteristics and the histological modifications in the leaf blade were evaluated for eight corn cultivars: landrace popcorn, ESALQ-popcorn, Piranao, DSCC-Architecture, ESALQ VF7, ESALQ VD8, JAB 01F and JAB 02D. The experimental de sign was a randomized complete block with three replications in a factorial arrangement. Plots were four rows wide and 6.00m long with 0.90m spacing between rows and 0.20m between plants. Nicosulfuron was applied at the dose of 160 g a.i.ha(-1), when the plants was 25 cm high and has 5-6 expanded leaves. Nicosulfuron significantly reduced plant height at silking and the Final plant stand. There was also a significant reduction for plant height at 47 clays after sowing, for number of leaves, ear position. ear height, grain yield, ear weight and total number of ears due to nicosulfuron. The cultivars JAB 01 and JAB 02 were the least affected by the herbicide with similar yields to those of the control group, showing good tolerance to nicosulfuron. The leaves injury symptoms for all the studied cultivars consisted of chlorosis and puckering of the blades from the expanding central leaves of the plant at 7 days after application. Anatomical alterations in the epidermis due to the herbicide consisted of an increase in number and size of the bulliform cells and in the suppression of the epidermal cells in the epidermis and in the nearby of the vascular bundles. Some parenchymatic cells became voluminous and devoid of chloroplasts. SEM examination revealed a loss of bilateral symmetry of the stomata and disappearance of the subsidiary cells from the stomata near the midrib at the adaxial surface.

Interferência de caruru-de-mancha sobre características de crescimento e produção da beterraba

A beterraba (Beta vulgaris), importante hortaliça cultivada no Brasil, é muito suscetível à interferência de plantas daninhas, sendo Amaranthus viridis uma das principais espécies encontradas em áreas de horticultura. O objetivo deste trabalho foi estudar a resposta da beterraba à competição com diferentes densidades de A. viridis, por meio da avaliação de características de crescimento e produção da cultura. Um experimento em caixas, com área útil de 0,25 m², foi conduzido em Jaboticabal-SP, Brasil, mantendo-se constante oito plantas por caixa de beterraba em convivência com 0, 1, 2, 3, 4 e 6 plantas por caixa de A. viridis. A cultura da beterraba foi muito suscetível à interferência imposta por plantas de A. viridis, tendo sua área foliar, número de folhas, massa seca de folhas, diâmetro médio da raiz e massa fresca de raízes significativamente reduzidos mesmo em baixas densidades populacionais da planta daninha; a massa fresca de raízes foi a mais sensível à interferência.

Respostas fisiológicas de diferentes clones de eucalipto sob diferentes regimes de irrigação

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Crescimento inicial e morfologia foliar em plantas de Enterolobium contortisiliquum (Vell.) Morong. E Erythrina velutina Mart. ex Benth, sob estresse hídrico

The Caatinga is the predominant vegetation type in semi-arid region of Brazil, where many inhabitants depend on hunting and gathering for survival, obtaining resources for: food and feed, folk medicine, timber production, etc. It‟s the dry ecosystem with highest population density in the world. The early stages of development are the most critical during the life cycle of a flowering plant and they‟re primordial to its establishment in environments exposed to water stress. Information about adjustments to the growth of the species, correlated with their studies of distribution in Seridó oriental potiguar, are an important ecological and economic standpoint, because they provide subsidies for the development of cultivation techniques, to programs of sustainable use and recovery of degraded areas. This thesis aimed to study the initial growth and foliar morphology in plants like Enterolobium contortisiliquum (Vell.) Morong. (tamboril) and Erythrina velutina Mart. ex Benth (mulungu), species of occurrence in the Caatinga, under water stress. After sowing and emergency, the seedlings were exposed to three water regimes: 450 (control), 225 (moderate stress) and 112.5 (severe stress) mm of water slide for 40 days. Seeding occurred in bags of 5 kg and after the establishment of seedlings thinning was carried out leaving a plantlet per bag. At the beginning the waterings occurred daily with distilled water, passing to be on alternate days after thinning. Twenty and forty days after the thinning seedlings collections were held to be done analysis of growth and biomass partition. When compared to the control group, the treatments with water stress showed reduction in the growth of the aerial part, growth of the greater root, number of leaves and leaflets, dry leaf area and total phytomass in both species, but in general, this effect was most marked for E. velutina. Regarding the partition of biomass, there were few changes throughout the experiment. Morphological changes in the leaves as a function of stress were not significant, however, there was a trend, in both species, to produce narrower leaves, that facilitate heat loss to the environment. It has not been possible to establish a positive relationship between inhibition of growth and distribution of species, whereas E. velutina is a species of most common occurrence in Seridó oriental potiguar. In this way, other aspects should be taken into account when studying the adaptation of species the dry environments, such as salinity, presence of heavy metals, wind speed, etc

Interferência de Euphorbia heterophylla no crescimento e acúmulo de macronutrientes da soja

O grau de interferência depende da densidade de plantas daninhas que infestam a soja. O objetivo deste trabalho foi avaliar características de crescimento e nutrição mineral da soja mantida em convivência com densidades crescentes de Euphorbia heterophylla. O experimento foi conduzido em Jaboticabal, SP, Brasil, entre outubro e dezembro de 2008, em vasos mantidos em campo aberto. Os tratamentos consistiram em submeter uma planta de soja por vaso à convivência com 0, 1, 2, 4, 8 e 16 plantas de E. heterophylla por vaso, da semeadura até o início do florescimento. Nesse período, avaliaram-se, apenas na soja, a altura e o número de trifólios, e em ambas as espécies, a matéria seca e o acúmulo de macronutrientes. Observou-se variação na altura de plantas e redução no número de trifólios e no acúmulo de matéria seca e macronutrientes da soja devido ao maior acúmulo de matéria seca e macronutrientes por densidades crescentes de E. heterophylla. Conclui-se que a soja mantida em convivência com E. heterophylla teve o crescimento e o acúmulo de macronutrientes reduzidos em razão da interferência imposta pela planta daninha.

Enxertia em citros por substituição de ápice caulinar

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Produção de chicória em função do período de cobertura com tecido de polipropileno

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)