Extra̧ão de Macro e Micronutrientes Pela Parte Aérea de Erva-Doce EM Fuņão de Calagem e Aduba̧ão com Esterco de Cama de Frango

A greenhouse experiment was conducted in the Soil Science Department of the Botucatu College of Agricultural Sciences (UNESP), Brazil, using a Dark Red Latosol in 25 L pots. The soil was limed to 50 and 70% of base saturation; and doses 0, 10, 20, 30 and 40 t ha-1 of chicken manure were applied, in December of 1999. The experimental design was completely randomized blocks with a factorial arrangement 5x2, 10 treatments and three replications. This work was carried to evaluate leaf number, height plants, fresh and dry weight by aerial part of sweet fennel, and macronutrients and micronutrients removal. The organic fertilization affected the accumulation of N, P, K, S, B and Mn; liming affected the nutrient uptake, except for the Ca, Mg, S and Fe; the interaction of factors affected K, Mg and Mn.

Alien fishes in lakes of the Doce river basin (Brazil): Range, new occurrences and conservation of native communities

The present study shows the distribution of alien fish species in tropical lakes in the middle Doce river basin, southeastern Brazil, obtained from a rapid assessment program. The causes for their introductions were sport-fishing improvement in some specific lakes and aquaculture in the studied basin. Presently, these species have a wide distribution occurring in 41 of the 54 lakes studied, representing an actual threat to regional native fish community. The natural connection among lakes and streams during the rainy season and the dispersal mediated by local people are the main invasion agents for alien fishes. The success of these invaders is probably due to absence of pre-existing effective competitors or top-predators in the invaded communities. We consider that the eradication of alien fishes by means of the available management tools may be very difficult due to the large number of lakes invaded and to the wide spectrum of lake conditions and resources exploited by these alien species. We recommend the use of environmental education as a tool to stop the human-mediated dispersion of aliens and to improve conservation of native fish community in lakes where these alien species are not present yet. © 2004 Instituto de Ciências Biológicas - UFMG.

Erosão hídrica de Latossolo Vermelho muito argiloso relevo ondulado em área de pós-plantio de eucalipto no Vale do Rio Doce, região Centro Leste do Estado de Minas Gerais

The erosion caused by running water constitutes important cause of environmental degradation and productivity reduction, which justifies its evaluation in areas of eucalypt commercial plantations, mainly in ondulated slope conditions. The present study was intended to evaluate the influence of different management systems, in an undulated eucalypt pos-planting area, upon soil and water losses by erosion. The experiment was installed in a very clayey Red Latosol (Oxisol) under three eucalypt management systems (downhill planting with burning of crop residues - EDq; downhill planting with maintenance of crop residues on soil surface - ED; level planting with maintenance of crop residues on soil surface - EN), native forest (FN), bare soil (SD), and native pasture (PN). The soil and water losses evaluations were performed in standard plots installed in the field. All eucalypt systems presented very low values of soil losses in relation to the established tolerance limit, indicating the adequacy of these management systems concerning water erosion. The sustainability of these environments regarding erosion is indicated by the fact that soil losses in eucalipt were very close to those observed in native forest (reference).

Policultivo do camarão de água doce Macrobrachium amazonicum (Heller, 1862) com a Tilápia do Nilo (Oreochromis niloticus) alimentadas com rações peletizada e farelada

The objective of this work was to evaluate the influence of fresh water shrimp Macrobrachium amazonicum (Heller, 1862) in performance of Nile tilapia (Oreochromis niloticus) cultivated in polyculture system and feeding with ration pelleted and mashed. The work was realized in Centro de Pesquisa em Aqüicultura Ambiental-CPAA/IAP - Toledo/PR during 37 days. Were utilized like experimental unit 16 ponds excavated, covered with concrete but with bottom of soil with dimension the 4 x 3 m and useful volume the 3,5 m 3. Were utilized 30 tilapias e 150 shrimps for experimental unit distributed at an entirely randomized design with 4 treatments and 4 replications, where TF: tilapia feeding with ration mashed; TCF: tilapia and shrimp feeding with ration mashed; TP: tilapia feeding with ration pelleted; TCP: tilapia and shrimp feeding with ration pelleted. The density used were the 2,6 fishes/m 2 with medium initial weight the 5,58 ± 0,10 g and initial length the 5,56 cm, and the density of shrimp was the 13 shrimps/m 2 with initial length the 1,04 cm. The temperature was gauged daily, while the variables dissolved oxygen, pH and electrical conductivity, weekly. The quantity of ration supplied was the 10% of total biomass of fishes, with feed frequency the 4 times a day, being corrected weekly in function of the biometry. During the experimental period the medium values of temperature, dissolved oxygen, pH and electrical conductivity of the ponds water were 23,42 ± 0,83°C, 5,32 ± 0,52 mg/L, 7,02 ± 0,39, e 100,96 ± 1,81 μS/ cm respectively. Won't registering any influence of shrimp during the cultivation and the ration pelleted provide the better conversion alimentary and performance of tilapias.

Sistema orgânico de produção de pescado de água doce

This study aimed to collect data about organic production of freshwater fish. Today the production of organic food of plant origin is predominant in the market, however, the animal rearing with organic certificate has great potential, and is an important tool for adding value to grains and organic products. Regarding the regulation of organic aquaculture, producers are based on international standards. In Brazil, the norms for breeding are very recent and their regulation was consolidated through Interministerial Instruction No28, published on June 8, 2001 by Ministério da Agricultura, Pecuária e Abastecimento (MAPA) together with Ministério da Pesca e Aquicultura (MPA). In the literature there are few studies with organic fish farm, but according to available data, the rearing of species such as tilapia (Oreochromis niloticus), pacu (Piaractus mesopotamicus) and jundia (Ramdhia sp) fed with organic diet, in different rearing systems, show results quite optimistic about the production system, which is the focus of this work.

Adubação nitrogenada e critérios de amostragem foliar para a cultura da batata

The present study aimed to determine which leave will be displayed and the time of collection of this leave. The treatments consisted on five doses of nitrogen, four times for collection sampling and three types of leaves, arranged in a randomized block design with three repetitions, totalizing one hundred and forty-four experimental units. The leaves collections took place every fifteen days at thirty, forty-five, sixty and seventy five days after budbreak (DAB), collecting the laminated / compound young leaf (first leave), newly mature (second leave) and the mature leave (third leave) from the set of terminal leaflets. For this was installed an experiment with the culture of potato (cv. Atlantic), in Barretos/SP, the period of march the june of 2010. According to this data collected in this study, the best time for collecting the leaves is at 30 days after the budbreak of the potato cultivation containing nitrogen concentrations in the leaves minus heterogeneous of plants from a fraction to another and with values R2 = 0.98 being higher to the all times of harvests. To the diagnostic leaf, the highest determination coefficient was observed in the newly mature (second leaf) with R2 = 0.98. It can be observed that the highest levels of nitrogen were found on the first leaf (39.01 kg-1). Nevertheless, the values were very heterogeneous and did not fit the curve being the second leave (newly mature) the one that best represents the nutritional status of the plant. Therefore the recommendation for nutritional diagnosis will collect the recently matured leaves (2nd leaf) 30 days after budbreak.

Doses e épocas de aplicação de nitrogênio em cobertura na qualidade fisiológica de sementes de milho doce

The amount and timing of nitrogen application can favor seed quality, such as increasing protein content, which is an important constituent for embryo development. The objective of this study was to evaluate the physiological quality of sweet corn seeds collected from plants cultivated with different dosages and timings of nitrogen top-dressing applications. Seeds of the BR 400 variety (Super Sweet) were used obtained from plants submitted to dosages of 0, 40, 80 and 120kg ha -1 of N in two top-dressing applications (vegetative and reproductive stages). The weight of 100 grains, germination, first count of germination test, dry weight of normal seedlings from the germination test, seedling growth, cold test, accelerated aging, tetrazolium vigor and electric conductivity and emergency speed rate were determined. Data was submitted to an analysis of variance using the F-test at the 5% level and second degree regression analysis. The dosage and time of application of nitrogen top-dressing did not affect seed weight or the germination of sweet corn seeds. An increase of the N top-dressing dosage, applied in the vegetative stage reduced the length of the aerial part, the root and the whole seedling.

Eficiência de utilização de nutrientes por cultivares de batata

The use of cultivars efficient in nutrient use is essential to increase yield and reduce production costs. The objective of this study was to evaluate absorption and nutrients use efficiency on five potato cultivars. The experiment was conduced in Itaí, São Paulo State, Brazil, in winter cropping season of 2008 on Oxisol. The experimental design was randomized blocks with split-plots and four replications. Plots comprised the five potato cultivars and subplots were established by sampling times, performed at planting and every seven days after emergence. At 97 DAP was calculated the nutrients use efficiency for dry matter production and at 122 DAP were calculated the nutrients use efficiency for fresh tuber and tuber dry matter yield. Mondial and Asterix cultivars showed greater dry matter production, higher fresh tubers yield and nutrients accumulation. Nutrients use efficiency for total dry matter and tubers dry matter, was similar among cultivars, but Ágata was more efficient in nutrients use efficiency for fresh tubers yield.

Análise de imagens no estudo da porosidade em latossolo cultivado com batata (Solanum tuberosum L.) sob dois sistemas de irrigação

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Crescimento, produtividade, acúmulo e exportação de nutrientes em cultivares de batata (Solanum tuberosum L.)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Determinação das características agronômicas, dos distúrbios fisiológicos, do estado nutricional da planta e da qualidade dos tubérculos em cultivares de batata (Solanum tuberosum L.)

Pós-graduação em Agronomia (Agricultura) - FCA

Estresse hídrico e adubação silicatada em batata (Solanum tuberosum L.) cv. Bintje

Pós-graduação em Agronomia (Agricultura) - FCA

Aspectos estruturais do hepatopâncreas do camarão de água doce Macrobracium amazonicum (Heller, 1862)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Caracterização do ciclo da vitelogênese do camarão de água doce Macrobrachium olfersi (Wiegmann, 1836) (Crustacea, Decapoda, Palaemonidae)

Pós-graduação em Ciências Biológicas (Biologia Celular e Molecular) - IBRC

Prevalência de hemogregarina em arraias de água doce (Potamotrygonidae) da região norte, com descrição de uma nova espécie de gênero

Pós-graduação em Biologia Geral e Aplicada - IBB