Photodynamic Therapy in Pythium insidiosum - An In Vitro Study of the Correlation of Sensitizer Localization and Cell Death

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

Root system and root and stem base organic reserves of pasture Tanzania grass fertilizer with nitrogen under grazing

The goal of this study was to evaluate the concentrations of non-structural carbohydrate (NSC) and of total nitrogen (N), as well as, to evaluate the root system in Tanzania-grass pastures fertilized with doses of urea in fall, spring and summer. The experiment was conducted at the Experimental Farm of Iguatemi, Maringa, Parana, Brazil, from March 2007 to March 2008. The experimental design was complete random blocks with subplots and four repetitions. The plots showed doses of N (50, 100 e 150 kg ha(-1) of N) plus the control (no N fertilization), and the subplots the season of the year. Root samples were taken at depths of 0-10, 10-20 and 20-40 cm. Root biomass showed a trend for mass accumulation up to a dosage of 100 kg ha(-1) for all seasons evaluated. Also, about 80% of the root system of Tanzaniagrass plants was found on the 0-10 cm layer for all dosages of N. Nitrogen fertilizer above 100 kg ha(-1) may foster fast forage plant growth reducing its NSC root storage capacity although favoring NSC and total N storage at stem base. NSC and total N concentrations were highest in fall, demonstrating that its usage is greater in spring due to the weather conditions being favorable to plant growth. In the regrowth, the largest reserve of total N was at the 0-10 cm root layer and the largest NSC reserve is at stem base.

CONTRIBUTION OF BASAL AND AERIAL TILLERS IN DYNAMICS OF HERBAGE PRODUCTION OF SIGNALGRASS AFTER GRAZING DEFERRED

During the spring, the understanding of regrowth in basal and aerial tillers of deferred pasture in winter it is necessary. Thus, the objective was to evaluate the morphogenesis and herbage accumulation during spring in Brachiaria decumbens cv. Basilisk (signalgrass) pasture used under deferred grazing in winter. The basal and aerial tillers in same pasture were evaluated. The signalgrass was managed with grazing cattle and with an average height of 25 cm. The randomized block design with three replications was adopted. The leaf appearance rate, phyllochron and the numbers of expanded, expanding and live leaves did not differ between basal and aerial tillers. The aerial tiller possessed lower rates of leaf senescence, of leaf elongation and of stem elongation, as well as lower number of dead leaf and stem and leaf lamina lengths, compared to basal tiller. The leaf lifespan was higher in aerial tillers than at basal. The basal tiller also contributed to higher rates of tissue growth and forage accumulation in pasture when compared to aerial tiller. After deferred grazing during the spring, the aerial tiller has low participation in forage production of signalgrass pasture.

TANZANIA GRASS STRUCTURE GRAZED BY GOATS MANAGED WITH DIFFERENT RESIDUAL LEAF AREA INDEX UNDER INTERMITTENT STOCKING

The objective of this study was to evaluate the structure of Tanzania grassland grazed by goats managed with different residue leaf area index (RLAI) under intermittent stocking. The experiment was carried out from February to August, 2008. The treatments consisted of three different targets RLAI (0.8, 1.6 and 2.4) and 95% light interception (LI) criterion determined the rest period. Forage samples were collected at average height sampling points and weighed. Subsequently, a smaller sample was removed to separate the morphological components (leaf, stem and dead material) and to determine the structural and productive features. The canopy architecture was evaluated by the method of inclined point quadrat. The pre-grazing height in the paddocks were significantly different among treatments. RLAI influenced dry matter contents of green forage, leaf, stem and total, with the exception of dry matter of dead material, where the lowest values were observed for 0.8 RLAI. Thus, RLAI modifies canopy structure and is sensitive to canopy height changes throughout the year. Pasture regrowth is not compromised by residual leaf area indexes between 0.8 and 2.4, when climatic factors are not limiting.

Desempenho de híbridos intraespecíficos de Brachiaria decumbens desenvolvidos por seleção recorrente recíproca

Pós-graduação em Agronomia (Genética e Melhoramento de Plantas) - FCAV

Degradabilidade ruminal da matéria seca de folhas e colmo de genótipos de Cynodon spp. em quatro idades de rebrota

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Comparison of different irrigants in the removal of endotoxins and cultivable microorganisms from infected root canals

This study was conducted to compare the effectiveness of different irrigants used to remove endotoxins and cultivable microorganisms during endodontic therapy. Forty root canals were contaminated and divided into groups according to the irrigant: 2% NaOCl + surfactant, 2% CHX, 2.5% NaOCl, and pyrogen-free saline solution (control). Samples were collected after root canal contamination (S1), after instrumentation (S2), and 7 days after instrumentation (S3). Microorganisms and endotoxins were recovered from 100% of the contaminated root canals (S1). At S2, 2% NaOCl + surfactant, 2% CHX, and 2.5% NaOCl were able to completely eliminate cultivable microorganisms. At S3, both 2% CHX and 2.5% NaOCl were effective in preventing C. albicans and E. coli regrowth, but E. faecalis was still detected. No microorganism species was recovered from root canals instrumented with 2% NaOCl + surfactant. At S2, a higher percentage value of endotoxin reduction was found for 2% NaOCl + surfactant (99.3%) compared to 2% CHX (98.9%) and 2.5% NaOCl (97.18%) (p < 0.05). Moreover, at S3, 2% NaOCl + surfactant (100%) was the most effective irrigant against endotoxins. All irrigants tested were effective in reducing microorganisms and endotoxins from root canals. Moreover, 2% NaOCl + surfactant was the most effective irrigant against endotoxins and regrowth of microorganisms.

Eficácia do glyphosate e 2,4-d no controle de commelina villosa

The aim of this study was to evaluate the efficacy of glyphosate and 2,4-D alone and in combination, in the control of Commelina villosa. We studied two methodologies for evaluating herbicide absorption in eight time intervals for washing (simulating rainfall after application) and cutting of leaves (simulating abortion as a defense strategy): 2, 4, 6, 8, 12, 24 and 48 hours after herbicide application, and a treatment without washing or cutting the leaves in a completely randomized design with four replications in a 3 x 7 + 1 factorial design (three herbicides x seven periods – hours after application). Herbicides and doses tested were: glyphosate (1,440 g ha-1), 2,4-D (720 g ha-1) and a mixture of glyphosate + 2,4-D (1,080 + 720 g ha-1). The simulation of rain interfered negatively in the plant control with glyphosate. The control with the herbicide 2,4-D was affected only for the period of 2 hours. Periods of rain simulation did not influence the control of plants with a mixture of glyphosate + 2,4-D. For the study with the cutting of treated leaves, all treatments regardless of the period of cutting the leaves were influenced negatively in terms of plant control, the plants showing regrowth when treated with 2,4-D alone.

Produção e qualidade de silagens de sorgo em sistema de integração lavoura-pecuária no cerrado de baixa altitude

Pós-graduação em Agronomia - FEIS

Avaliação de um sistema florestal de curta rotação de Eucalyptus spp. em função da desbrota e adubação

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)