Impacto de herbicidas em isolados de Trichoderma spp.

O uso de microrganismos é uma alternativa para o controle de doenças em plantas. Todavia, é prudente verificar a interação desse com os demais métodos de controle empregados em determinada cultura. Dessa forma, objetivou-se avaliar a fungitoxicidade dos herbicidas sobre o crescimento e desenvolvimento dos isolados de Trichoderma spp. Utilizou-se o delineamento inteiramente casualizado, em esquema fatorial 6 x 6 x 4, com quatro repetições. O fator A correspondeu aos herbicidas pendimethalin, clomazone, carfentrazone-ethyl, oxadiazon, thiobencarb + propanil e byspiribac-sodium; o fator B, às doses dos herbicidas - 0, 25, 50, 75, 100 e 200% da dose recomendada; e o fator C, aos isolados de Trichoderma spp. AJAM 18, CE 66, TRI 01 e TRI 02. O ensaio foi realizado em condições in vitro; avaliaram-se o crescimento micelial radial (CMR) e a esporulação dos isolados após aplicação dos herbicidas. Observaram-se diferenças de sensibilidade dos isolados para o mesmo produto testado. O oxadiazon reduziu o CMR dos isolados AJAM 18 e TRI 01 em 66 e 35%, respectivamente. No entanto, reduziu apenas 16% do CMR do isolado TRI 02 e não alterou o CMR do isolado CE 66 mesmo em 200% da dose recomendada. Verificaram-se diferentes efeitos dos produtos em cada isolado. A mistura comercial de thiobencarb+propanil foi altamente tóxica aos isolados de Trichoderma spp., com reduções em torno de 85% no CMR e no número de esporos. Por outro lado, o byspiribac-sodium pouco afetou os isolados, apresentando reduções inferiores a 10% no CMR e na esporulação. O carfentrazone-ethyl e byspiribac-sodium demonstraram ser compatíveis com os isolados de Trichoderma spp. estudados.

Biological Activity of Quinoline Alkaloids from Raulinoa echinata and X-ray Structure of Flindersiamine

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

Interação silício-imidacloprid no comportamento biológico e alimentar de Schizaphis Graminum (Rond.) (Hemiptera: Aphididae) em plantas de trigo

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Mass fractal characteristics of silica sonogels as determined by small-angle x-ray scattering and nitrogen adsorption

A sample series of silica sonogels was prepared using different water-tetraethoxysilane molar ratio (r(w)) in the gelation step of the process in order to obtain aerogels with different bulk densities after the supercritical drying. The samples were analyzed by means of small-angle x-ray-scattering (SAXS) and nitrogen-adsorption techniques. Wet sonogels exhibit mass fractal structure with fractal dimension D increasing from similar to2.1 to similar to2.4 and mass-fractal correlation length xi diminishing from similar to13 nm to similar to2 nm, as r(w) is changed in the nominal range from 66 to 6. The process of obtaining aerogels from sonogels and heat treatment at 500degreesC, in general, increases the mass-fractal dimension D, diminishes the characteristic length xi of the fractal structure, and shortens the fractal range at the micropore side for the formation of a secondary structured particle, apparently evolved from the original wet structure at a high resolution level. The overall mass-fractal dimension D of aerogels was evaluated as similar to2.4 and similar to2.5, as determined from SAXS and from pore-size distribution by nitrogen adsorption, respectively. The fine structure of the secondary particle developed in the obtaining of aerogels could be described as a surface-mass fractal, with the correlated surface and mass-fractal dimensions decreasing from similar to2.4 to similar to2.0 and from similar to2.7 to similar to2.5, respectively, as the aerogel bulk density increases from 0.25 (r(w)=66) up to 0.91 g/cm(3) (r(w)=6).

Purification, partial characterization and preliminary X-ray diffraction analysis of a mannose-specific lectin from Cymbosema roseum seeds

A lectin from Cymbosema roseum seeds (CRL) was purified, characterized and crystallized. The best crystals grew in a month and were obtained by the vapour-diffusion method using a precipitant solution consisting of 0.1 M Tris-HCl pH 7.8, 8% (w/v) PEG 3350 and 0.2 M proline at a constant temperature of 293 K. A data set was collected to 1.77 angstrom resolution at a synchrotron-radiation source. CRL crystals are orthorhombic, belonging to space group P2(1)2(1)2(1). Crystallographic refinement and full amino-acid sequence determination are in progress.

Qualidade e composição química da carne de bovinos de corte inteiros ou castrados de diferentes grupos genéticos Charolês x Nelore

Seventy beef males of three breeding systems (BS), straightbreds Charolais (Ch) and Nellore (Ne), G1 crossbreds: 1/2 Ch + 1/2 Ne (1/2 Ch) and 1/2 Ne + 1/2 Ch (1/2 Ne) and G2 crossbreds: 3/4 Ch + 1/4 Ne (3/4 Ch) and 3/4 Ne + 1/4 Ch (3/4 Ne) were used. The number of animals by genetic group was, respectively, 15, 12,8, 12,14 and 9. Thirty-five males were castrated (C) at seven months and 35 were kept intact (1). The animals were feedlot finished from 20 to 24 months. The longissimus dorsi muscle was used for the meat evaluation. No significant interaction was observed between genetic composition and sexual condition, for the variables studied. The I males displayed meat with darker color (3.05 vs. 3.78 points) with less amount of marbling (4.26 vs. 5.75 points) and less amount of ether extract (1.73 vs. 2.88%). However they presented larger (66.03 vs. 60.50 cm(2)) longissimus dorsi area and meat with better palatability, juiciness and tenderness. Ch animals had larger longissimus dorsi than the Ne. In the G I group, the 1/2 Ch meat showed larger amount of marbling and ether extract and less cooking losses than the 1/2 Ne meat. Between G2 animals, the 3/4 Ne showed meat with larger thawing losses and larger amount of ether extract. In G1 animals meat, the heterosis level reached 18.54% for longissimus dorsiarea, 28.10% for ether extract and 64.01% for amount of marbling. In G2, the heterosis was -17.30% for lean texture and 10.40% for longissimus dorsi area.

INFLUENCE OF DIETARY-PROTEIN INTAKE AND RECOMBINANT HUMAN SOMATOTROPIN ADMINISTRATION ON GROWTH AND BODY-COMPOSITION OF JUVENILE TAMBACU (A PIARACTUS-MESOPOTAMICUS X COLOSSOMA-MACROPOMUM CROSS)

This experiment was undertaken to study the interaction between level of dietary protein and recombinant human somatotropin (rhGH) administration on performance and body composition of juvenile tambacu (a crossbred Brazilian fish). A total of 72 juvenile tambacu, initially weighing and measuring (mean +/- s.e.m.) 23 +/- 2 g and 9 +/- 0.5 cm, respectively, were randomly divided into 18 groups of 4 fish each. Water temperature was 28 degrees C. Triplicate groups received one of two levels of dietary protein (15 and 30% as fed basis) and one of 3 doses of rhGH (0, 2 and 4 mu g/g) via intraperitoneal injection twice a week for 6 weeks, using a randomized complete block design. Somatotropin was noted to stimulate linear and body weight gain. The higher protein level supported increased growth in weight and length, but there was no interaction between protein level and rhGH dose for either parameter. Protein efficiency ratio and percentage protein deposited showed higher values on diets containing 15% protein. Somatotropin treatment did not significantly affect body composition, but there was a trend towards improved protein retention and reduced carcass lipid. In conclusion, the results of this experiment suggest that rhGH is able to stimulate linear gain in tambacu.

Purification, crystallization and preliminary X-ray diffraction analysis of carboxyhaemoglobin-II from the fish Piaractus mesopotamicus (pacu)

Carboxyhaemoglobin-II isolated from the pacu (Piaractus mesopotamicus) has been crystallized and X-ray diffraction data were collected to 2.0 Angstrom resolution using synchrotron radiation. Crystals were characterized as belonging to the space group I23; preliminary structural analysis reveals the presence of one dimer in the asymmetric unit.

Synthesis, spectroscopic characterization and X-ray crystallographic studies of trans-[PtCl2(PEt3)(PySOR)] complexes, where PySOR=(2-methylsulphinyl)-pyridine and (2-n-propylsulphinyl)pyridine

Alkylsulphinylpyridine ligands containing three potential donor centres: N, S and O atoms and two complexes of general formula trans-[PtCl2(PEt3)PySOR)] (R = Me and Pr-n) were prepared and characterized by elemental analysis, i.r. spectroscopy, H-1- and P-31-n.m.r. and X-ray crystallography. The ambidentate ligands act in both situations as monodentate ligands, bonded to the metal exclusively through the nitrogen atom. The crystal structures revealed the occurrence of discrete molecules and, in both complexes, the Pt atoms are coordinated in square planar arrangements by two chloride ions, in a trans configuration, by the pyridine nitrogen atom, and by the phosphine P atom. The oxygen atoms do not take part in the complexation scheme.

Molecular modeling and small angle X-ray scattering studies of Hoplosternum littorale cathodic haemoglobin

Considerable interest is currently focused on fish haemoglobins in order to identify the structural basis for their diversity of functional behavior. Hoplosternum littorale is a catfish that presents bimodal gill (water)/gut (air) -breathing, which allows this species to survive in waters with low oxygen content. The hemolysate of this fish showed the presence of two main haemoglobins, cathodic and anodic. This work describes structural features analyzed here by integration of molecular modeling with small angle X-ray scattering. Here is described a molecular model for the cathodic haemoglobin in the unliganded and liganded states. The models were determined by molecular modeling based on the high-resolution crystal structure of fish haemoglobins. The structural models for both forms of H. littorale haemoglobin were compared to human haemoglobin. (C) 2004 Elsevier B.V. All rights reserved.

Crystallization and preliminary X-ray diffraction analysis of XAC1151, a small heat-shock protein from Xanthomonas axonopodis pv. citri belonging to the alpha-crystallin family

The hspA gene (XAC1151) from Xanthomonas axonopodis pv. citri encodes a protein of 158 amino acids that belongs to the small heat-shock protein ( sHSP) family of proteins. These proteins function as molecular chaperones by preventing protein aggregation. The protein was crystallized using the sitting-drop vapour-diffusion method in the presence of ammonium phosphate. X-ray diffraction data were collected to 1.65 angstrom resolution using a synchrotron-radiation source. The crystal belongs to the rhombohedral space group R3, with unit-cell parameters a = b = 128.7, c = 55.3 angstrom. The crystal structure was solved by molecular-replacement methods. Structure refinement is in progress.

Trichloro-bridged diruthenium (III,III) complexes: X-ray isomorphous structures of [Ph3X=O center dot center dot center dot H center dot center dot center dot O=XPh3][Ru2Cl7(XPh3)(2)]center dot 0.5(CH2Cl2)(H2O)(X = As or P)

The triply chloro-bridged binuclear complexes [Ph3X=O...H...O=XPh3][Ru2Cl7(XPh3)(2)].0.5(CH2Cl2) (H2O) (X = As or P) were obtained from [RuCl3(XPh3)(2)DMA].DMA (DMA = dimethylacetamide) CH2Cl2/Et2O solution. The structures were characterized by X-ray diffraction studies. The complexes are formed from two Ru atoms bridged by three chloride anions. The two ruthenium atoms are also coordinated to two non-bridging Cl atoms and an AsPh3 or PPh3 ligand respectively. As an interesting feature, the cations of these complexes are protons, trapped in a very short hydrogen bond between two triphenylarsine or triphenylphosphine oxide molecules.

Efeito da ovariectomia em novilhas Nelore x Angus, Bos taurus indicus x Bos taurus taurus sobre os ganhos de peso

This study aimed to evaluate the weight gain in cross breed heifers Nelore X Angus, spayed and nonspayed, kept on pasture and confinement. The animals were allotted in two groups as follows: group I consisted of 30 nonspayed heifers with 18 months old. Group 2 was composed of 30 spayed heifers with 18 months old. The animals were allotted in pasture of Brachiaria decumbens and weighted at 39 and 75 days. Significant difference was observed between the average daily gain of the two groups - G1 and G2 (75(th) day), respectively (0.51 kg and 0.65 kg; P<0.0 1). The following day (761 day), all animals were allotted and kept on confinement during 144 days. Significant difference was observed between the average daily gain of the two groups - G I and G2 (1441 day), respectively (0.73 kg and 0.58 kg; P<0.0 1). The results of this experiment show that spayed heifers presented a higher daily gain on pasture.

Dermal mast cell counts in F2 Holstein x Gir crossbred cattle artificially infested with the tick Boophilus microplus (Acari : Ixodidae)

The role of dermal mast cells (DMC) in the host resistance to ticks has been studied but it is not totally explained yet. Studies have proposed that zebuine cattle breeds, known as highly resistant to ticks, have more DMC than taurine breeds. In the present study, we compared the number of adult female ticks Boophilus microplus and the mast cells' countings in the skin of F-2 crossbred Gir x Holstein cattle, before and after tick infestation. F-2 crossbred cattle (n = 148) were divided into seven groups and artificially infested with 1.0 x 10(4) B. nticroplus larvae and, 21 days afterwards, adult female-fed ticks attached to the skin were counted. Skin biopsies were taken and examined under light microscopy with a square-lined ocular reticulum in a total area of 0.0625 mm(2) in both the superficial and deep dermis. Results demonstrated that infested F-2 crossbred cattle acquired resistance against the cattle-tick B. microplus probably associated to an increase in the dermal mast cell number. It is concluded that the tick infestation may lead to an environmental modification in the dermis of parasitized hosts due to the massive migration of mast cells or their local proliferation.