Biological features of a puzzling symbiotic association between the hermit crab Dardanus insignis and the porcellanid crab Porcellana Sayana (Crustacea)

The symbiotic lifestyle is widespread among porcellanid crabs, which maintain ecological and co-evolutionary associations with annelid polychaetes, poriferans, cnidarians, echinoderms, gastropod. mollusks, and other crustaceans such as shrimps and hermit crabs, among others. We investigated the ecological association between the hermit crab Dardanus insignis and the porcellanid Porcellana sayana, in southeastern Brazil. Porcellanid crabs, hermit crabs, and available shells were collected monthly from July 2001 to June 2003, with a shrimp boat equipped with two double-rig trawl nets. The majority of P. sayana specimens were collected in shells occupied by D. insignis (96.6%); a few were found in empty shells (3.4%). The catch of both symbionts and hosts increased with increasing depth, with the highest occurrence at 35 m. The F. sayana crabs of various sizes could be found solitary or forming aggregations of up to 14 individuals per host, showing no sex or size segregation. In spite of the high diversity of shell species occupied by the hermit crabs and also available in the field, only a few of them were also utilized by P. sayana. The majority (93%) of shells utilized by P. sayana also hosted other symbiont species, constituting the basis of extensive symbiotic complexes. Thus, the ecological relationship between D. insignis and P. sayana may be classified as a non-obligate and non-specific symbiosis that may also involve other facultative organisms such as sea anemones. (C) 2008 Elsevier B.V. All rights reserved.

Nesting architecture and population structure of the fungus-growing ant Cyphomyrmex transversus (Formicidae: Myrmicinae: Attini) in the Brazilian coastal zone of Ilheus, Bahia

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Evaluation of the possible role of ants (Hymenoptera: Formicidae) as mechanical vectors of nematodes and protists

Os Nematoda e Protista podem ser transmitidos ao homem de diversas maneiras, mas pouca ênfase é dada para a transmissão mecânica por intermédio de formigas. Assim, esse trabalho procurou investigar a transmissão mecânica de ovos de Ascaris lumbricoides e cistos de Entamoeba coli pelos Formicidae. Através de experimentos com espécies mantidas em ninhos no laboratório (Tapinoma melanocephalum, Linepithema humile e Monomorium pharaonis) e com 17 espécies de formigas de uma área antropizada na região de Mogi as Cruzes (SP), foi possível constar que os ovos A. lumbricoides foram transportados por L. humile, tanto no campo (1 operária) como no laboratório (1 operária), por Camponotus rufipes (2), por Solenopsis saevissima (1) e por Acromyrmrex niger (1). em três operárias de C. rufipes foram encontrados cistos de E. coli. Apesar da baixa incidência de transporte, as três primeiras espécies pelo fato de viverem muito próximas ao ser humano, podem levar para dentro do ambiente domiciliar patógenos de Nematoda e Protista.

Genetic associations between age at first calving and heifer body weight and scrotal circumference in Nelore cattle

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Subdosages of Bacillus thuringiensis on Plutella xylostella) (Lepepidoptera: plutellidae) and Trichogramma pretiosum (Hymenoptera: trichogrammatidae)

The aim of this paper was to evaluate the biological aspects of Plutella xylostella and Trichogramma pretiosum in eggs of the F2 generation of P. xylostella under the influence of Bacillus thuringiensis in laboratory conditions. The experiment was conducted in the Laboratorio de Biologia and Criacao de Insetos of Faculdade de Ciencias Agrarias e Veterinarias de Jaboticabal - UNESP reen collars contaminated with strains and commercial product based on B. thuringiensis in the laboratory. The eggs obtained from the F2 generation of P. xylostella evaluated the biological parameters of T. pretiosum. It was observed that some biological characteristics of P. xylostella showed changes by the treatment with B. thuringiensis. The viability of the larvae and pupae stages, pupae weight were the biological parameters more influenced by treatments, with values significantly reduced when compared to control. However, the larvae length and pupae stages and sex ratio were similar in all treatments, with no significant biological variations. Thus, this bacterium isolated from this behavior may provide greater exposure of larvae to other natural enemies as well as generation of adults less viable, which makes them potential programs in pest control, since the interaction of the methods of control is one of the main ways to enhance the biological control of insect pests. It was observed sublethal effects on P. xylostella biology, and B. thuringiensis negative influence on the parasitism capacity and emergency of T. pretiosum.

Enhanced solubilization of iron and calcium phosphates by Aspergillus niger by the addition of alcohols

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

Physical attributes of kaolinitic and oxidic oxisols resulting from different usage systems

A mineralogia da fração argila e os sistemas de uso exercem fundamental importância na estrutura do solo. Assim, objetivou-se avaliar atributos físicos de um Latossolo Vermelho Distrófico, caulinítico (LVd), e, de um Latossolo Vermelho Eutroférrico, oxídico (LVef), sob diferentes sistemas de uso, localizados no município de Jaboticabal (SP), Brasil. Os sistemas de uso foram: cana-de-açúcar; algodão e mata. Foram avaliadas a densidade do solo, porosidade total, macro e microporosidade, nas profundidades de 0,0-0,1, 0,1-0,2, 0,2-0,3, 0,3-0,4 m. O Latossolo caulinítico (LVd) apresentou maior densidade do solo e menor porosidade total, macro e microporosidade. O uso aumentou a densidade do solo na profundidade de 0,0-0,3 m, com efeitos maiores no Latossolo caulinítico, principalmente na profundidade de 0,1-0,2 m na área cultivada com cana-de-açúcar.

Liming and postharvest quality of carambola fruits

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

Soil resistance to penetration and least limiting water range for soybean yield in a haplustox from Brazil

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

Impact of atmosphere, organic acids, and calcium on quality of fresh-cut 'Kensington' mango

Fresh-cut slices from ripe 'Kensington' mango (Mangifera indica L.) were prepared aseptically and stored under various treatments at 3 degrees C. Treatments included reduced oxygen (2.5%), enhanced carbon dioxide (5-40%), organic acid application, calcium chloride application, and combinations of the above. Symptoms limiting shelf-life were characterised by tissue darkening, development of a 'glassy' appearance, surface desiccation, and loss of firmness. Reduced oxygen (2.5%) was effective at controlling tissue darkening and the development of a 'glassy' appearance, while calcium application (3%) was partly effective at controlling darkening. Calcium chloride however significantly slowed (but did not stop) loss of tissue firmness. Carbon dioxide (5-40%) and citric acid had little positive effect on shelf-life, with both treatments appearing to promote tissue softening. A combination of low oxygen and calcium allowed 'Kensington' slices to be held for at least 15 days at 3 degrees C. (C) 2006 Elsevier B.V All rights reserved.

Mortality of Bemisia tabaci biotype B (sternorrhyncha: aleyrodidae) adults by aliphatic and aromatic synthetic sucrose esters

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

Response of minimally processed carambola to chemical treatments and low-oxygen atmospheres

Fresh-cut carambola (Averrhoa carambola L.) has limited marketability due to cut-surface browning. The effect of chemical treatments (ascorbic acid, citric acid and Ca-EDTA), controlled atmosphere (0.4-20.3% O-2) and the association of these processes was investigated. Post-cutting dip and low-oxygen atmospheres did not prevent discoloration or improve sensory and physicochemical parameters. However, ascorbic acid (0.5% and 1%) dips reduced polyphenol oxidase (PPO) activity during storage at 4.5 degrees C, with 1% ascorbic acid inducing the lowest activity. Although cut-surface browning of 'Maha' slices was not relevant, carambola slices treated with 1% ascorbic acid in association with 0.4% oxygen did not present significant browning or loss of visual quality for up to 12 days, 3 days longer than low oxygen alone (0.4% O-2), thus, their quality can be significantly improved by combining both treatments. (c) 2007 Elsevier B.V. All rights reserved.

Crystallization and preliminary X-ray diffraction analysis of a glutathione S-transferase from Xylella fastidiosa

Glutathione S-transferases (GSTs) form a group of multifunctional isoenzymes that catalyze the glutathione-dependent conjugation and reduction reactions involved in the cellular detoxification of xenobiotic and endobiotic compounds. GST from Xylella fastidiosa (xfGST) was overexpressed in Escherichia coli and purified by conventional affinity chromatography. In this study, the crystallization and preliminary X-ray analysis of xfGST is described. The purified protein was crystallized by the vapour-diffusion method, producing crystals that belonged to the triclinic space group P1. The unit-cell parameters were a = 47.73, b = 87.73, c = 90.74 angstrom, alpha = 63.45, beta = 80.66, gamma = 94.55 degrees. xfGST crystals diffracted to 2.23 angstrom resolution on a rotating-anode X-ray source.

Genetic aspects of productive and reproductive traits in a Murrah buffalo herd in São Paulo, Brazil

This study investigated genetic trends of some productive and reproductive traits in a herd of Murrah buffalo raised in São Paulo, Brazil. Variance components for milk production (Mr), length of lactation (LL), calving interval (CI) and age of first calving (AFC) were estimated by che restricted maximum likelihood method, using an animal model. Estimated heritability values were 0.38; 0.01; 0.10 and 0.20 for MP, LL, CI and AFC, respectively. Estimated repeatability values were 0.50, 0.13 and 0.20 for MP, LL and CI, respectively. Means of predicted breeding values for cows, dams and sires according to calving year and the genetic correlations were presented.

Qualitative-feed-restricted heavy swine: meat quality and morpho-histochemical characteristics of muscle fibers

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