Ichthyotoxicity of Chattonella marina (Raphidophyceae) to damselfish (Acanthochromis polycanthus): the synergistic role of reactive oxygen species and free fatty acids

This investigation aimed to elucidate the relative roles of putative brevetoxins, reactive oxygen species and free fatty acids as the toxic principle of the raphidophyte Chattonella marina, using damselfish as the bioassay. Our investigations on Australian C. marina demonstrated an absence or only very low concentrations of brevetoxin-like compounds by radio-receptor binding assay and liquid chromatography-mass spectroscopy techniques. Chattonella is unique in its ability to produce levels of reactive oxygen species 100 times higher than most other algal species. However, high levels of superoxide on their own were found not to cause fish mortalities. Lipid analysis revealed this raphidophyte to contain high concentrations of the polyunsaturated fatty acid eicosapentaenoic acid (EPA; 18-23% of fatty acids), which has demonstrated toxic properties to marine organisms. Using damselfish as a model organism, we demonstrated that the free fatty acid (FFA) form of EPA produced a mortality and fish behavioural response similar to fish exposed to C. marina cells. This effect was not apparent when fish were exposed to other lipid fractions including a triglyceride containing fish oil, docosahexaenoate-enriched ethyl ester, or pure brevetoxin standards. The presence of superoxide together with low concentrations of EPA accelerated fish mortality rate threefold. We conclude that the enhancement of ichthyotoxicity of EPA in the presence of superoxide can account for the high C. marina fish killing potential. (C) 2003 Elsevier B.V All rights reserved.

Impact of commercial fishing on Trindade Island and Martin Vaz Archipelago, Brazil : characteristics, conservation status of the species involved and prospects for preservation

Reportamos atividades de pesca comerciais no complexo insular mais afastado da costa brasileira: Ilha da Trindade e Arquipélago Martin Vaz. As atividades foram estudadas através de embarques e entrevistas com os mestres e pescadores das embarcações durante uma expedição cientifica realizada entre fevereiro e abril de 2007. Quatro modalidades de atividades de pesca são realizadas na região, capturando ao menos sete espécies que possuem algum risco de extinção. O estabelecimento de normas específicas de restrição para atividades que pescam sobre os recifes das ilhas é uma alternativa para a conservação das espécies ameaçadas. O monitoramento das embarcações pode ocorrer via satélite através do programa nacional de rastreamento de embarcações pesqueiras (PREPS).

Revison of Alongatepyris (Hymenoptera: Bethylidae) with description of a new species from Colombia

Espécies do gênero Neotropical Alongatepyris Azevedo são raramente coletadas. O gênero é reconhecido dentre os Sclerodermini por possuir o corpo extremamente achatado e a célula submediana da asa anterior pequena e completamente fechada. É descrita e ilustrada uma segunda espécie, Alongatepyris ingens sp. nov. da Colômbia. Esta espécie é caracterizada por não possuir a nervura radial da asa anterior. É apresentada uma diagnose de A. platunissimus Azevedo, 1992. É apresentada uma chave para as espécies do gênero.

Characterization of the types of the Neotropical Pseudisobrachium (Hymenoptera: Bethylidae), with a key to species

Atualmente é difícil reconhecer a identidade de muitas espécies neotropicais de Pseudisobrachium Kieffer, 1904, principalmente por que as descrições e ilustrações disponíveis não são suficientes para permitir identificações precisas. Para resolver este problema, foram examinadas 115 espécies válidas, além de seus sinônimos juniores. Foram realizados doze atos nomenclaturais, e reconhecidas 110 espécies válidas para a região Neotropical. Foram designados dois lectótipos: Pristocera crassicornis Westwood and Pristocera haemorrhoidalis Westwood. Foram propostas sete sinonímias novas para espécies: Pseudisobrachium retusum Evans syn. nov. de P. pauxillum Evans; P. cunco Perez syn. nov. de P. erythrocephalum Evans; P. navajo Evans, P. rectangulatum Evans, P. emarginatum Evans e P. foutsi Evans syn. nov. de P. flavinervis Fouts; P. acuminatum Waichert & Azevedo syn. nov. de P. latum Waichert & Azevedo. Foi proposta a seguinte sinonímia nova para gênero: Parisobrachium Kieffer syn. nov. de Dissomphalus Ashmead. Foi estabelecida a seguinte combinação nova e revalidado o nome: Dissomphalus albipes (Kieffer) comb. nov. e nom. rev. de Pseudisobrachium paraguayense Kieffer.

A new species of Solepyris Azevedo (Hymenoptera, Bethylidae) from Brazil, with amended diagnosis of the genus

Solepyris Azevedo é um gênero neotropical raramente coletado. O gênero é reconhecido dentre os gêneros de Sclerodermini por possuir a nervação das asas anteriores com apenas uma célula fechada grande. É descrita e ilustrada uma segunda espécie, Solepyris montuosus, sp. nov., do Brasil. Esta espécie é caracterizada por possuir a nervura radial da asa anterior longa. É incluída uma diagnose emendada de Solepyris unicus Azevedo. Foi fornecida uma chave para as duas espécies de Solepyris.

New species of Apenesia (Hymenoptera, Bethylidae) from the Parque Nacional da Serra do Divisor, Acre, Brazil

Ten new species of Apenesia Westwood, 1874, from Brazil, Acre, are described and illustrated. They belong, respectively, to the following species-groups: nitida group, Apenesia lobata sp. nov., A. serrulata sp. nov. and A. subangulata sp. nov.; laevigata group, A. ocullata sp. nov. and A. rostrum sp. nov.; columbana group, A. apicilata sp. nov.; mexicana group, A. triapicalis sp. nov.; brasiliensis group, A. megaventris sp. nov., A. ventosa sp. nov. and A. triangula sp. nov. New geographical records and some morphological data on A. funebris Evans, 1963, A. nitida (Kieffer, 1910) and A. truncaticeps (Kieffer, 1910) are added.

New species of Bakeriella (Hymenoptera, Bethylidae) from the New World and new data on geographic distribution

Bakeriella lata sp. nov. (Brazil, Rondônia), Bakeriella aurata sp. nov. (Brazil, Amazonas) and Bakeriella sulcaticeps sp. nov. (Brazil, Amazonas) are described and illustrated. New geographic records and variation data for B. cristata Evans, 1964, B. floridana Evans, 1964, B. flavicornis Kieffer, 1910, B. incompleta Azevedo, 1994, B. mira Evans, 1997, B. montivaga (Kieffer, 1910), B. olmeca Evans, 1964 and B. subcarinata Evans, 1965 are provided. The male of B. incompleta is described for the first time.

New species and notes on Dissomphalus (Hymenoptera, Bethylidae) from Estação Biológica de Santa Lúcia, Santa Teresa, ES, Brazil

Five new species of Dissomphalus Ashmead, 1893 are described and illustrated, all from Espírito Santo, Brazil: D. h-ramus, D. verrucosus, D. laminaris, D. cristatus and D. scopatus. New geographic records and variation data of D. scamatus Azevedo, 1999, D. concavatus Azevedo, 1999, D. rectilineus Azevedo, 1999, D. vallensis Evans, 1979, D. gilvipes Evans, 1979, D. plaumanni Evans, 1964, D. napo Evans, 1979, D. truncatus Azevedo, 2003 and D. cornutus Evans, 1964 are included.

Opções de manejo de Neoleucinodes elegantalis (Guenée), (Lepidoptera: Crambidae) com bases biológicas e controle mecânico, biológicos e extratos de plantas

A broca-pequena-do-fruto, Neoleucinodes elegantalis (Guenée) (Lepidoptera: Crambidae) é uma praga de grande importância na cultura do tomateiro. Desta forma, métodos de manejo que auxiliem no controle dessa praga e que reduzam a aplicação de agrotóxicos devem ser estudados. O objetivo do presente trabalho foi avaliar métodos alternativos de manejo da broca-pequena-do-fruto, como: o controle biológico, através da utilização de parasitoides do gênero Trichogramma e nematoides entompatogênicos (Heterorhabditis indica e Sterneneima carpocapsae); o controle físico, por meio do ensacamento de cachos de tomate com o tecido-não-tecido (TNT); e o controle químico através do estudo da atividade inseticida de plantas como a pimenta, o fumo, o alho e a mamona nas fases embrionárias, larval, pupal e adulta. Desta forma, por meio das análises foi possível verificar que a espécie e/ou linhagem de Trichogramma que mais se destacou foi T. galloi (Tg1) com características biológicas favoráveis ao manejo de N. elegantalis. Para os nematoides entomopatogênicos, S. carpocapsae, foi o mais efetivo, causando uma mortalidade de 82,93% a uma concentração de 65 juvenis infectivos por pré-pupa da broca-pequena-do-fruto. Através do ensacamento dos frutos, foi possível verificar a redução na oviposição da praga em frutos do tomateiro para quase zero com sacolas de TNT com fundo fechado, não ocorrendo alteração no peso, pH e graus brix do fruto, enquanto que no controle químico através de inseticidas botânicos foi possível verificar o destaque do extrato aquoso de fumo, reduzindo a oviposição, entrada e saída das lagartas nos frutos; causando mortalidade na fase embrionária, lagarta, pré-pupa e pupa da broca-pequena-do-fruto.

Species richness of anthophilous butterflies of an Atlantic Forest fragment in Southeastern Brazil

The objectives of this study were to identify anthophilous butterflies on psychophilous flowers of four Asteraceae species in an Atlantic Forest fragment in Viçosa, Minas Gerais State, Southeastern Brazil, and to determine whether there are species in common with other lepidopteran inventories of the Southeastern and Midwestern regions of Brazil. It is the first inventory of anthophilous butterflies of a semideciduous forest fragment in Zona da Mata, State of Minas Gerais. A total of 108 species were recorded, representing the fourth largest lepidopteran survey in this State. The results demonstrated that Asteraceae species may be important tools for monitoring anthophilous butterflies. The similarity with other inventories ranged from 1 to 92.55%. Fifteen species were reported for the first time in the State of Minas Gerais, and among them, Melanis alena and Thisbe irenea were observed in this study only.

Soybean growth and yield after single tillage and species mixture of cover plants

The use of cover crops is important for the agricultural crop and soil management in order to improve the system and, consequently, to increase yield. Therefore, the present study analyzed the effect of crop residues of black oat (Avena strigosa Schreb.) (BO) and a cocktail (CO) of BO, forage turnip (Raphanus sativus L.) (FT) and common vetch (Vicia sativa L.) (V) on the emergence speed index (ESI), seedling emergence speed (SES) plant height and soybean yield in different intervals between cover crop desiccation with glyphosate 480 (3 L ha-1) and BRS 232 cultivar sowing. Plots of 5 x 2.5 m with 1 m of border received four treatments with BO cover crops and four with CO as well as a control for each cover crop, at random, with five replications. The plots were desiccated in intervals of 1, 10, 20 and 30 days before soybean seeding. The harvest was manual while yield was adjusted to 13% of moisture content. The experimental design was completely randomized with splitplots and means compared by the Scott and Knott test at 5% of significance. The results showed that CO of cover crops can be recommended for soybean to obtain a more vigorous seedling emergence, from 10 days after cover crop desiccation.

Phytomass production and nutrient accumulation by green manure species

Green manuring is recognized as a viable alternative to improve nutrient cycling in soils. The aim of this study was to evaluate the phytomass production and nutrient accumulation in shoots of the summer green manures jack bean [Canavalia ensiformis (L.) DC.], dwarf pigeon pea (Cajanus cajanvar var. Flavus DC.), dwarf mucuna [Mucuna deeringiana (Bort) Merr] and sunn hemp (Crotalaria juncea L.), under nitrogen fertilization and/or inoculation with N-fixing bacteria. A split plot design was arranged with the four Fabaceae species as main plots and nitrogen fertilization (with and without) and inoculation with diazotrophic bacteria (with and without) as the subplots, in a 2² factorial. The experiment was arranged as a randomized complete block design with four replications. In the conditions of this trial, the sunn hemp had the highest production of shoot phytomass (12.4 Mg ha-1) and nutrient accumulation, while the dwarf mucuna had the lowest production of shoot phytomass (3.9 Mg ha-1) and nutrient accumulation. The results showed no effect of nitrogen fertilization or inoculation with N-fixing bacteria on the production of shoot phytomass and nutrient accumulation, except for inoculation without nitrogen fertilization, resulting in greater P accumulation (p <0.05) in the sunn hemp and greater Zn and Mn accumulation in the dwarf mucuna. These findings indicate that N fertilization or inoculation with N2-fixing bacteria for Fabaceae are low efficiency practices in the edaphoclimatic conditions of this study.

A new species of Culex (Melanoconion) from Southern Brazil (Diptera: Culicidae)

A new species from Southern Brazil, named Culex (Melanoconion) ribeirensis is described. The description includes adults, pupal and larval stages, illustrating the morphological aspects and a picture of a breeding place. Some data about known distribution and bionomics are presented.

Vector competence experiments with Rocio virus and three mosquito species from the epidemic zone in Brazil

First-generation progeny of field-collected Psorophora ferox, Aedes scapularis, and Aedes serratus from the Rocio encephalitis epidemic zone in S.Paulo State, Brazil, were tested for vector competency in the laboratory. Psorophora ferox and Ae. scapularis are susceptible to per os infection with Rocio virus and can transmit the virus by bite following a suitable incubation period. Oral ID50S for the two species (10(4.1) and 10(4.3) Vero cell plaque forming units, respectively) did not differ significantly. Infection rates in Ae. serratus never exceeded 36%, and, consequently, an ID50 could not be calculated for this species. It is unlikely that Ae. serratus is an epidemiologically important vector of Rocio virus. The utility of an in vitro feeding technique for demonstrating virus transmission by infected mosquitoes and difficulties encountered in working with uncolonized progeny of field-collected mosquitoes are discussed.