Accumulation of dry mass and macronutrients by sourgrass plants

The experiment was carried out aiming to analyze the dry mass production and distribution and the content and accumulation of macronutrients in sourgrass (Digitaria insularis) plants cultivated under mineral nutrition standard conditions. Plants grew in 7-liter pots filled with sand substrate and daily irrigated with nutrient solution, being maintained under greenhouse conditions. Treatments consisted of times of evaluation (21, 35, 49, 63, 77, 91, 105, 119, and 133 days after emergence - DAE) and were arranged in a completely randomized design with four replicates. Sourgrass showed small accumulation of dry mass (0.3 g per plant) and macronutrients (3.7 mg of N per plant, 0.4 mg of P per plant, 5.6 mg of K per plant, 0.9 mg of Ca per plant, 0.7 mg of Mg per plant, and 0.3 mg of S per plant) at vegetative growth stage (< 49 DAE). Those accumulations increased mainly after 77 DAE, reaching the maximum theoretical value at 143, 135, 141, 129, 125, 120, and 128 DAE, for dry mass (12.4 g per plant), N (163.2 mg per plant), P (27.1 mg per plant), K (260.5 mg per plant), Ca (47.6 mg per plant), Mg (30.9 mg per plant), and S (13.7 mg per plant), respectively. K and N were found with higher rates and, as a consequence, they were required and accumulated in greater amounts in plant tissues of sourgrass.

Estudo comparativo do acúmulo de massa seca e macronutrientes por plantas de Zea mays e Ipomoea hederifolia

Two experiments were carried out under greenhouse conditions to study the accumulation and distribution of dry mass and macronutrients in maize and Ipomoea hederifolia. Plants of both species had grown, separately, in pots with sand substrate and irrigation with nutrient solution. Treatments were represented by the times of evaluation, realized in intervals of 14 days, starting at 21 days after emergence (DAE). A maize plant showed slight growth up to 30 DAE, when dry mass allocation was higher in roots and leaves (80%); while an I. hederifolia plant, up to 50 DAE, when the allocation of dry mass was higher in offshoots and leaves (79). Dry mass accumulation was almost five times greater in maize (134 g per plant) than in I. hederifolia (29 g per plant). The average values of N and K contents were greater in I. hederifolia. Maximum accumulations of macronutrients by maize were 1,431; 474; 1,832; 594; 340, and 143 mg per plant, while by I. hederifolia, 727; 52; 810; 350; 148, and 65 mg per plant, for N, P, K, Ca, Mg, and S, respectively. Mean accumulation rate of dry mass and macronutrients by maize plants was crescent up to 87 DAE, reaching the maximum value at 103 DAE; while being crescent up to 121 DAE by I. hederifolia plants, reaching the maximum value at 138 DAE. Thus, beyond the interference on harvesting process, a population of I. hederifolia also can compete with maize crop for nutrients.

Crescimento e nutrição mineral de Sida rhombifolia

This experiment was carried out to analyze dry mass production and distribution, and the content and accumulation of macronutrients in arrowleaf sida (Sida rhombifolia) plants cultivated under mineral nutrition standard conditions. Plants grew in seven liter pots filled with sand substrate and daily irrigated with nutrient solution, under greenhouse conditions. Treatments consisted of times of evaluation (21, 35, 49, 63, 77, 91, 105, 119, and 133 days after emergence - DAE) and were arranged in a completely randomized design with four replicates. Arrowleaf sida plants showed small accumulation of dry mass (0.3 g per plant) and macronutrients (6.9 mg N per plant, 0.7 mg P per plant, 8.6 mg K per plant, 4.9 mg Ca per plant, 2,6 mg Mg per plant, and 0.3 mg S per plant) at the vegetative growth stage (< 49 DAE). Those accumulations increased, mainly after 63 DAE, and the daily accumulation rate was crescent up to 94 DAE (dry mass - DM), 89 DAE (N and P), 98 DAE (K), 95 DAE (Ca and S), and 93 DAE (Mg), when there was accumulation of 26.3 g DM per plant, 402.6 mg N per plant, 45.6 mg P per plant, 359.3 mg K per plant, 337.6 mg Ca per plant, 71.9 mg Mg per plant, and 20.9 mg S per plant. N and K had the highest rates and, consequently, were the most required and accumulated in greater amounts in plant tissues of arrowleaf sida.

Alternative substrates in the production of lettuce seedlings and their productivity in the field

Based on the hypothesis that alternative substrates should improve the yield of lettuce crops by producing better quality seedlings, the objective of this work was to evaluate the effect of different substrates on the production of seedlings of this species, and their growth in the field. The study was in two stages. The first consisted of the production of lettuce seedlings, and the second assessed their development in the field. Four alternative substrates were tested, obtained by mixing together a sieved vermicompost from which all clumps had been removed, sterilized sand, charred rice husks and basalt powder. The commercial substrate, Plantmax HA®, was also tested. In the first phase, which was conducted in a completely randomised design with four replications, the height, root length, number of leaves, leaf area and dry weight of the seedlings were all evaluated 28 days after sowing. In the second phase, which was carried out in the field in a randomised block design with four replications, the plants were harvested 50 days after transplanting and the head diameter, fresh weight, number of leaves and leaf and stem dry weight were evaluated. The alternative substrates produced larger seedlings in less time than the commercial substrate, resulting in a reduction of 10 days in the total crop cycle. The reduction in the time between sowing and harvesting, together with those aspects relating to sustainability, are the main advantages of the use of alternative substrates, since in the field crop production did not differ between treatments.

Poço de infiltração para controle de enchentes na fonte: avaliação das condições de operação e manutenção

This study investigated the following aspects regarding a soakaway, i.e. an infiltration well: i) entrance filter device; ii) permeability of the geotextile; and iii) emptying time. The 3.6 m³ infiltration well drains a roof area of 241.8 m². The entrance device is made up of layers of sand, gravel and geotextile set on a metal structure. The concrete rings that form the lateral walls were covered with geotextile, and bricks were laid between the soil and concrete rings. The infiltration well remained in operation during the entire testing period, and specific events were simulated to measure the emptying time. Permeability and fine particle tests were carried out after eight months of operation. Samples of geotextile taken from the bottom, the walls and the entrance device presented average permeability reductions of approximately 50.7%, 7.7% and 21.2%, respectively. The sand in the entrance device retained around 34.8% of fine particles and the gravel retained 0.13% in the same period. The infiltration rate was approximately 34.7 mm/h. The R2 coefficient for measured and calculated times was 0.97.

Infecção por Fusarium graminearum e Fusarium verticillioides em sementes de milho

The previous knowledge of the infection process and pathogens behavior, for evaluating the physiological potential of maize seeds, is essential for decision making on the final destination of lots that can endanger sowing. This research was carried out in order to study the minimum period required for maize seeds contamination by Fusarium graminearum Schwabe and Fusarium verticillioides (Sacc.) Nirenberg, as well as these pathogens influence on seed germination and vigor, by using the cold test. Three maize seeds hybrids, kept in contact with the pathogens for different periods, were evaluated with and without surface disinfection. After determining the most suitable period, new samples were contaminated by F. graminearum and F. verticillioides, under different infection levels, and subjected to germination tests in sand. The cold test was conducted with healthy and contaminated seeds, at different periods, in a cold chamber. The contact of maize seeds with F. graminearum and F. verticillioides for 16 hours was enough to cause infection. F. graminearum and F. verticillioides did not affect the maize seeds germination, however, F. graminearum reduced the vigor of seeds lots.

Cultivation of Agaricus blazei in the environmental protection area of the Baturité region under three types of casing soils

The outdoor cultivation (ditches) of Agaricus blazei was evaluated in the protected natural area (APA) of the mountainous region of Baturité on three types of casing soils (A, B and C). Casing soil A (horizon A) of the local soil was used (Alfisol). Casing B was obtained with a mixture of 30% of eucalyptus charcoal (1-2 cm of length) and 70% of horizon B of the local soil. Casing C was composed of 25% of vermiculite, 25% of coconut fiber and 50% of coarse sand. Temperature, relative humidity and pluviometric rates were monitored. The physical-chemical properties of the three casing soils were analyzed. The effect of the casing soil on the number and weight of the mushrooms, productivity, yield and biological efficiency of A. blazei were evaluated. The yield, productivity, biological efficiency and number of mushrooms were higher when using soil A. The highest productivity for soil A was attributed mainly to the physical characteristics, which were considered more appropriate for the cultivation, in addition to the high pluviometric rates and relative humidity. The productivity with soil A (9.62%) is comparable with the average productivity obtained in Brazil, meaning that the cultivation of A. blazei in this APA may have good perspectives for cultivation.

Liberdade de expressão e discurso do ódio: um exame sobre as possíveis limitações à liberdade de expressão

In a view to determining the outlines of the Freedom of Speech and to specify its contents, we face hate speech as an offensive and repulsive manifestation, particularly directed to minority groups in contemporary society. Thus, the study sought to promote, in the foreground, a study of the Freedom of Speech, in the liberal molds. Considered this way, Freedom of Speech will tend to accept hate speech as a legitimate manifestation, albeit at the injury of the victims. On the other hand, when we are dealing with the exhaustion of the liberal paradigm and the affirmation of the Welfare State, we note the recognition by the social state of the asymmetries and commitment to redistributive justice. The Freedom of Speech, warded by welfare state will tend to suffer major restrictions on its self-determination power, rejecting hate speech.

Propagação do pinhão manso por estaquia, enxertia e sementes

Pós-graduação em Agronomia - FEIS

Caracterização de um latossolo em sistemas agroflorestais e mata com o uso de análise estatística multivariada

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Efeitos da contaminação fecal sobre a dinâmica e a estrutura da alça microbiana em areias de praias do litoral norte do estado de São Paulo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Sintese e aplicação de filmes biocomponentes nanoestruturados de 'TI'/'TI''O IND.2'/'W''O IND.3' por template e 'SI'/'TI''O IND.2'/'PT' por heterojunção em conversão de energia solar e remediação ambiental

Pós-graduação em Química - IQ

Comparação entre diferentes técnicas de moldagem utilizando transferentes específicos para implantes de hexágono interno: esquema all-on-4

Pós-graduação em Reabilitação Oral - FOAR

Metodologia de curvatura de bambu laminado colado (BLAC) para fabricação de mobiliário: diretrizes para o design

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

A similaridade no uso do microhabitat por girinos (Amphibia, Anura) reflete processos ecológicos ou filogenéticos?

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