Bioactivity of Indonesian mahogany, Toona sureni (Blume) (Meliaceae), against the red flour beetle, Tribolium castaneum (Coleoptera, Tenebrionidae)

Bioactivity of Indonesian mahogany, Toona sureni (Blume) (Meliaceae), against the red flour beetle, Tribolium castaneum (Coleoptera, Tenebrionidae). The insecticidal activity of Toona sureni (Blume) Merr. was evaluated considering repellency, mortality and progeny production of F1 adults of Tribolium castaneum (Herbst, 1797) (Coleoptera, Tenebrionidae). Dried extract of seeds of T. sureni was dissolved in acetone to prepare solution of various concentrations (0.5, 1.0, 2.5 and 5.0%). To test for repellency, the insects were exposed to treated filter paper. Mortality of larvae, pupae and adults was evaluated by the treatment of spraying the insects with different concentrations of T. sureni extract. Residual effect of the extract was also evaluated considering the production of progeny of F1 adults. The highest repellency (93.30%) of T. castaneum occurred at the highest concentration (5.0% suspension of T. sureni); while the lowest (0.0%) repellency occurred at 0.5% suspension after 1 day of treatment. The highest mortality against adults (86.71%), larvae (88.32%) and pupae (85%) occurred at 5% suspension at 8 days after application. There was a negative correlation between the concentrations of T. sureni and the production of F1 adult's progeny of T. castaneum. The highest number of progeny (147) of T. castaneum occurred in the control at 7 days after treatment; and the lowest number of progeny (43) occurred at 5.0% concentration in 1 day after treatment. The results show that T. sureni is toxic to T. castaneum and has the potential to control all stages of this insect in stored wheat.

Developmental biology, polymorphism and ecological aspects of Stiretrus decemguttatus (Hemiptera, Pentatomidae), an important predator of cassidine beetles

Developmental biology, polymorphism and ecological aspects of Stiretrus decemguttatus (Hemiptera, Pentatomidae), an important predator of cassidine beetles. Stiretrus decemguttatus is an important predator of two species of cassidine beetles, Botanochara sedecimpustulata (Fabricius, 1781) and Zatrephina lineata (Fabricius, 1787) (Coleoptera, Cassidinae), on the Marajó Island, Brazil. It attacks individuals in all development stages, but preys preferentially on late-instar larvae. Its life cycle in the laboratory was 43.70 ± 1.09 days, with an egg incubation period of six days and duration from nymph and adult stages of 16.31 ± 0.11 and 22.10 ± 1.67 days, respectively. The duration of one generation (T) was 12.65 days and the intrinsic population growth rate (r) 0.25. These data reveal the adjustment of the life cycle of S. decemgutattus with those of the two preys, but suggest greater impact on Z. lineata. However, no preference over cassidine species was shown in the laboratory. Up to 17 different color patterns can be found in adults of S. decemguttatus, based on combinations of three basic sets of color markings. Some of them resemble the markings of chrysomelids associated with Ipomoea asarifolia (Convolvulaceae) and are possibly a mimetic ring. Three color patterns were identified in nymphs, none of which was associated with any specific adult color pattern.

Volatilização de N-NH3 na cultura de milho: I. efeito da irrigação e substituição parcial da uréia por sulfato de amônio

Foi desenvolvido um experimento em latossolo vermelho-escuro muito argiloso fase cerrado, no Centro de Pesquisas Novartis-Seeds, Uberlândia (MG), para avaliar o efeito da irrigação e do N-uréia, em cobertura no milho, e de sua substituição parcial por sulfato de amônio, nas perdas de N-NH3 volatilizado. O N foi aplicado aos 25 e 36 dias após plantio, sendo os tratamentos dispostos em blocos casualizados com quatro repetições: testemunha, uréia com irrigação anterior e posterior à aplicação de N nas duas coberturas e uréia + sulfato de amônio (relação N:S = 2,1:1) na primeira cobertura e uréia na segunda com irrigação anterior e posterior à aplicação. Nove amostragens de N-NH3 volatilizado foram efetuadas em intervalos de quatro a cinco dias, utilizando-se coletores do tipo semi-aberto estático, instalados logo após a primeira aplicação de N. Com irrigação posterior à adubação, as perdas acumuladas de N-NH3 foram de 40,6 e 23,0 % do N aplicado para os tratamentos com adubação exclusiva de uréia e substituição parcial com sulfato de amônio respectivamente. Com irrigação prévia, as perdas acumuladas foram, respectivamente, de 42,8 e 38,6 % do N aplicado. Embora não tenha havido diferença significativa entre os tratamentos, a substituição da uréia por sulfato de amônio foi positiva quando a irrigação foi efetuada após a adubação. Esse tratamento mostrou também o maior diâmetro de caule, altura de planta e teor foliar de nutrientes. O rendimento de grãos respondeu positivamente à aplicação de N. A correlação das perdas por volatilização de N-NH3 mostrou um ajuste linear inverso à produtividade dos tratamentos adubados, de tal forma que 19,3 kg ha-1 de grãos deixaram de ser produzidos por quilograma de N volatilizado.

Volatilização de N-NH3 na cultura de milho:: II. avaliação de fontes sólidas e fluidas em sistema de plantio direto e convencional

Foram desenvolvidos dois experimentos em campo, em sistema de plantio direto (SPD) sobre cobertura de aveia-preta, em latossolo vermelho-escuro, distrófico, argiloso, e em sistema de plantio convencional (SPC), após cultivo de soja, em latossolo vermelho-amarelo distrófico arenoso, no Centro de Pesquisa Novartis-Seeds e na Fazenda Stª. Teresinha, Uberlândia (MG) respectivamente. O estudo objetivou avaliar as perdas por volatilização de N-NH3 da cobertura nitrogenada na cultura de milho com cerca de 100 kg ha-1 de N, de cinco fontes nitrogenadas em ambos os sistemas de plantio. As fontes nitrogenadas - sulfato de amônio, nitrato de amônio, uréia e duas soluções nitrogenadas constituídas de uréia + nitrato de amônio (uran) e uréia + nitrato de amônio + sulfato de amônio (sulfuran) - foram aplicadas na superfície e incorporadas no meio da entrelinha. Após a aplicação da cobertura, instalaram-se, ao acaso, três coletores do tipo semi-aberto estático, por tratamento, sendo efetuadas seis amostragens de N-NH3 volatilizado, em intervalos de quatro a cinco dias. No SPD, as perdas acumuladas de N-NH3 provenientes das fontes uréia, uran e sulfuran aplicadas na superfície foram, respectivamente, de 78,0; 37,2 e 26,9% do N aplicado. No SPC, as perdas mais significativas foram de uréia (30,7%) e uran (9,7%). O nitrato de amônio e o sulfato de amônio apresentaram perdas inferiores a 15,0% do N aplicado à superfície. A correlação das perdas por volatilizacão de N-NH3 e a produtividade dos dois experimentos mostraram um ajuste linear negativo, de tal forma que no SPD houve uma queda de produção de 13,3 kg de grãos e no SPC, de 11,8 kg de grãos para cada quilograma de N volatilizado.

ORANGE You Interested In Pumpkins...., 2009

The most popular use of pumpkins may be for jack-o-lanterns and fall decorations but they have many more uses. When selecting a pumpkin for cooking, the best selection is a “pie pumpkin” or “sweet pumpkin.” These are smaller than the large jack-o-lantern pumpkins and the flesh is sweeter and less watery. You can substitute the jack-o-lantern variety with fairly good results. Pumpkin seeds can be used in tossed salads, casseroles, soups, and other baked goods, either ground or whole. Although roasted pumpkin seeds tend to be better-tasting, you'll receive higher nutritional value from the raw seeds. So decorate your place with a pumpkin and make something. This brochure produced by The Department of Agriculture and Land Stewardship.

Experiencias en sistema controlado para la obtención de semillas de concha de abanico Argopecten purpuratus (Lamarck, 1819) . Ilo, Moquegua

IMARPE Ilo obtuvo financiamiento del Gobierno Regional de Moquegua en base al proyecto "Mejoramiento de infraestructura e implementació n de laboratorio de investigació n de molusc"os, para construir un laboratorio experimental con el objetivo de desarrollar técnicas de reproducción artificial de moluscos nativos de la Región, para la obtención de semillas principalmente de macha Mesodesma donacium, chanque Concholepas concholepas y pulpo Octopus mimus. Este informe contiene el resultado de las actividades realizadas el 2007,en relación a la aplicación de técnicas de cultivo de microalgas (alimento vivo) y obtención de semillas de concha de abanico.

Qualitat microbiològica dels productes vegetals frescos mínimament processats i desenvolupament de tecnologies de bioconservació mitjançant bacteris de l'àcid làctic

Food safety today is conditiones by the implementation of new Tecnologies for food preservation based on mild treatments and mínimum process, Novel foods, severe restrictions in the toxicològic profile of chemical preservatives, And the drastic limitation /prohibition of antibiotics, and as a consequence, by the New emergint pathogens or by the increase of classical food-borne pathogens. Biopreservatives appear within this context with strong expectations, because thei are safe microorganisms of ten isolated from foods, chemical compounds of natural origin -antimicrobial peptides and proteins, botanical extracts, enzymes- and sintetic compounds based on natural structures, but less toxic and more eficients, like the amtimicrobial peptides. Among the microbial biopreservatives, lactic acid bacteria have shown great possibilities in the preservation of cured meat products, ready to eat fresh fruit and vegetables, as well as to decrease microbial spoilage in food by products before processing for valorization. Our laboratory has performed an extense survey of the microbiological quality of fresh fruit and vegetables, and of ready-to-eat products, and have detect low levels, but significant of Salmonella sp., E. coli and Listeria spp., including L.monocytogenes, in retail markets and Supermarkets of Catalonia. Due to this reason, we started a project consisting of Developing application of lactic acid bacteria (LAB) obtained from these products, as biopreservatives. LAB were abundant in ready-to-eat fresh fruits and vegetables, specially in germinated seeds. From these products we obtained strains of Leuconostoc, Lactobacillus and Weissella, producing bacteriocins and with a Significant activity of control of L.monocytogenes in fresh apple and cut salad. Ather strains were efective in the inhibition of fungal rot during postharvest caused by Penicillium expansum

Balanço da adubação nitrogenada sólida e fluida de cobertura na cultura de milho, em sistema plantio direto no Triângulo Mineiro (MG)

Foi desenvolvido um experimento com as fontes uréia e uran aplicadas superficialmente ou incorporadas (5-7 cm) na cobertura nitrogenada de milho, no sistema plantio direto, com o objetivo de efetuar, na colheita, um balanço do N-uréia (15N) e quantificar as perdas por volatilização de N-NH3 nesses tratamentos, assim como nos adicionais, testemunha e misturas de uréia + KCl (sólida) e uran + KCl (fluida), na formulação 6-0-9 (N-P2O5-K2O), aplicadas somente em superfície. Os tratamentos originaram-se de um fatorial 1 + (2 x 2) + 2, sendo a testemunha + o fatorial 2 x 2 (duas fontes; uréia e uran x duas formas de localização) + dois tratamentos adicionais, misturas uréia + KCl (sólida) e uran + KCl (fluida), dispostos em blocos casualizados com quatro repetições. O ensaio foi realizado em Latossolo Vermelho-Escuro muito argiloso fase cerrado relevo plano, no Centro de Pesquisa Novartis - Seeds do município de Uberlândia (MG). Cerca de 100 kg ha-1 de N foram aplicados no estádio fenológico de seis a oito folhas. Após 26 dias da adubação, as perdas acumuladas de N-NH3 nos tratamentos em superfície foram de 54, 41, 17 e 14% do N aplicado, para uréia, uréia + KCl, uran e uran + KCl, respectivamente. Quando a uréia e o uran foram incorporados ao solo, as perdas acumuladas de N-NH3 foram de 5,0 e 3,5% do N aplicado, respectivamente. Na colheita, o N da uréia absorvido pela planta (raízes + colmos + folhas + grãos) foi de 19,9 kg ha-1 (20,8% do N aplicado) e de 29,5 kg ha-1 (29,5% do N aplicado), quando aplicado na superfície e incorporado, respectivamente. O N-uréia do uran absorvido pela planta foi de 11,4 kg ha-1 (26,1% do N aplicado) e de 11,7 kg ha-1 (26,8% do N aplicado), quando aplicado na superfície ou incorporado, respectivamente. O N da uréia imobilizado na camada de 0-45 cm de profundidade foi, em média, de 9,9 kg ha-1 (10,0% do N aplicado), da aplicação superficial ou incorporada, e do N-uréia do uran foi de 3,3 kg ha-1 (7,6% do N aplicado). O N-mineral no solo derivado do N da uréia e do N-uréia do uran aplicados na superfície, no perfil de 0-150 cm, foi, respectivamente, de 2,4 e 3,2%, e de 5,9 e 2,5%, com as fontes incorporadas. No balanço global de N, em média, 13,7 e 50,3% do N da uréia não foram recuperados no sistema solo-planta, respectivamente, para a aplicação superficial ou incorporada; para o N-uréia do uran, obtiveram-se, respectivamente, 47,7 e 57,6%.

Structure-function characterization and optimization of a plant-derived antibacterial peptide.

Crushed seeds of the Moringa oleifera tree have been used traditionally as natural flocculants to clarify drinking water. We previously showed that one of the seed peptides mediates both the sedimentation of suspended particles such as bacterial cells and a direct bactericidal activity, raising the possibility that the two activities might be related. In this study, the conformational modeling of the peptide was coupled to a functional analysis of synthetic derivatives. This indicated that partly overlapping structural determinants mediate the sedimentation and antibacterial activities. Sedimentation requires a positively charged, glutamine-rich portion of the peptide that aggregates bacterial cells. The bactericidal activity was localized to a sequence prone to form a helix-loop-helix structural motif. Amino acid substitution showed that the bactericidal activity requires hydrophobic proline residues within the protruding loop. Vital dye staining indicated that treatment with peptides containing this motif results in bacterial membrane damage. Assembly of multiple copies of this structural motif into a branched peptide enhanced antibacterial activity, since low concentrations effectively kill bacteria such as Pseudomonas aeruginosa and Streptococcus pyogenes without displaying a toxic effect on human red blood cells. This study thus identifies a synthetic peptide with potent antibacterial activity against specific human pathogens. It also suggests partly distinct molecular mechanisms for each activity. Sedimentation may result from coupled flocculation and coagulation effects, while the bactericidal activity would require bacterial membrane destabilization by a hydrophobic loop.

Soybean response to starter nitrogen and Bradyrhizobium inoculation on a Cerrado oxisol under no-tillage and conventional tillage systems

In Brazil, Bradyrhizobium inoculation has successfully replaced the use of N fertilizer on soybean [Glycine max (L) Merr.] crops. However, with the expansion of no-tillage cropping systems in the Cerrados region, the idea that it is necessary to use small N rates at the sowing to overcome problems related with N immobilization has become widespread, mainly when soybean is cultivated after a non-legume crop. In this study we examined soybean response to small rates of N fertilizer under no-tillage (NT) and conventional tillage (CT) systems. Four experiments (a completely randomized block with five replicates) were carried out in a red yellow oxisol, during the periods of 1998/1999 and 1999/ 2000, under NT and CT. The treatments consisted of four urea rates (0, 20, 30 and 40 kg ha-1 N). All treatments were inoculated with Bradyrhizobium japonicum strains SEMIA 5080 and SEMIA 5079, in the proportion 1 kg of peat inoculant (1,5 x 10(9) cells g-1) per 50 kg of seeds. In both experiments, soybean was cultivated after corn and the N fertilizer was band applied at sowing. In all experiments, N rates promoted reductions of up to 50 % in the nodule number at 15 days after the emergence. Regardless of the management system, these reductions disappeared at the flowering stage and there was no effect of N rates on either the number and dry weight of nodules or on soybean yields. Therefore, in the Brazilian Cerrados, when an efficient symbiosis is established, it is not necessary to apply starter N rates on soybean, even when cultivated under notillage systems.

Identidad nacional, lengua y escuela = National identity, language and school

La globalización cuestiona la existencia de una relación mimética entre ciudadanía y Estado-nación. Las identidades homogéneas, sustentadas ideológicamente en nociones como «lengua nacional», plantean problemas en sociedades en las que ha crecido espectacularmente la diversidad lingüística e identitaria. Cataluña es un territorio en el que una parte de la población afirma una identidad catalana distinta a la española y viceversa. Además, se ha teorizado que la identidad catalana y la lengua catalana coexisten mutuamente. Por eso, se suceden voces que defienden la presencia del catalán en la educación escolar como fuente de la identidad nacional catalana, mientras que otras voces defienden su presencia simplemente como una buena manera de aprender el catalán cuando no se puede aprender en el medio social y familiar. En los últimos años, Cataluña ha recibido casi un millón de personas extranjeras que han modificado notablemente su situación sociolingüística. Las últimas encuestas manifiestan que un 6,3% de la población utiliza habitualmente una lengua distinta del catalán y del castellano. En este marco, mostramos las construcciones identitarias de un grupo de adolescentes de origen extranjero que están en el segundo ciclo de la ESO. Los datos fueron recogidos mediante dos grupos de discusión de seis-siete estudiantes de distinto origen, lengua propia y tiempo de residencia en Cataluña. Los resultados muestran la importancia del lugar de origen en la construcción de la identidad. Además, los participantes que afirman sentimientos catalanes o españoles no los relacionan con la lengua sino con los intercambios sociales que han establecido con sus iguales de origen naciona. Las intervenciones muestran también las dificultades para promover identidades múltiples desde el contexto escolar que eviten actitudes racistas y xenófobas y sirvan para promover proyectos colectivos de futuro en los que se pueda vivir desde una cierta diferencia

Level of accumulation of epoxy fatty acid in Arabidopsis thaliana expressing a linoleic acid delta12-epoxygenase is influenced by the availability of the substrate linoleic acid.

Arabidopsis thaliana (L.) Heynh. expressing the Crepis palaestina (L.) linoleic acid delta12-epoxygenase in its developing seeds typically accumulates low levels of vernolic acid (12,13-epoxy-octadec-cis-9-enoic acid) in comparison to levels found in seeds of the native C. palaestina. In order to determine some of the factors limiting the accumulation of this unusual fatty acid, we have examined the effects of increasing the availability of linoleic acid (9cis, 12cis-octadecadienoic acid), the substrate of the delta12-epoxygenase, on the quantity of epoxy fatty acids accumulating in transgenic A. thaliana. The addition of linoleic acid to liquid cultures of transgenic plants expressing the delta12-epoxygenase under the control of the cauliflower mosaic virus 35S promoter increased the amount of vernolic acid in vegetative tissues by 2.8-fold. In contrast, the addition to these cultures of linoelaidic acid (9trans, 12trans-octadecadienoic acid), which is not a substrate of the delta12-epoxygenase, resulted in a slight decrease in vernolic acid accumulation. Expression of the delta12-epoxygenase under the control of the napin promoter in the A. thaliana triple mutant fad3/fad7-1/fad9, which is deficient in the synthesis of tri-unsaturated fatty acids and has a 60% higher level of linoleic acid than the wild type, was found to increase the average vernolic acid content of the seeds by 55% compared to the expression of the delta12-epoxygenase in a wild-type background. Together, these results reveal that the availability of linoleic acid is an important factor affecting the synthesis of epoxy fatty acid in transgenic plants.

Leaf senescence of common bean plants as affected by soil phosphorus supply

Responses of leaf senescence to P supply could constitute adaptive mechanisms for plant growth under P-limiting conditions. The aim of this study was to evaluate the effects of soil P supply on leaf senescence of common bean (Phaseolus vulgaris L.). Eight P levels, ranging from 5 to 640 mg kg-1 P, were applied to pots containing four bean plants of cultivar Carioca in 10 kg of an Oxic Haplustult soil. Attached leaves were counted weekly, abscised leaves were collected every other day, and seeds were harvested at maturity. The number of live leaves increased until 48 days after emergence (DAE) and decreased afterwards, irrespective of applied P levels. At lower applied P levels, the initial increase and the final decrease of leaf number was weak, whereas at higher applied P levels the leaf number increased intensively at the beginning of the growth cycle and decreased strongly after 48 DAE. Dry matter and P accumulated in senesced leaves increased as soil P levels increased until 61 DAE, but differences between P treatments narrowed thereafter. The greatest amounts of dry mass and P deposited by senesced leaves were observed at 48-54 DAE for high P levels, at 62-68 DAE for intermediate P levels and at 69-76 DAE for low P levels. These results indicate that soil P supply did not affect the stage of maximal leaf number and the beginning of leaf senescence of common bean plants, but the stage of greatest deposition of senesced leaves occurred earlier in the growth cycle as the soil P supply was raised.

Spatially and genetically distinct control of seed germination by phytochromes A and B.

Phytochromes phyB and phyA mediate a remarkable developmental switch whereby, early upon seed imbibition, canopy light prevents phyB-dependent germination, whereas later on, it stimulates phyA-dependent germination. Using a seed coat bedding assay where the growth of dissected embryos is monitored under the influence of dissected endosperm, allowing combinatorial use of mutant embryos and endosperm, we show that canopy light specifically inactivates phyB activity in the endosperm to override phyA-dependent signaling in the embryo. This interference involves abscisic acid (ABA) release from the endosperm and distinct spatial activities of phytochrome signaling components. Under the canopy, endospermic ABA opposes phyA signaling through the transcription factor (TF) ABI5, which shares with the TF PIF1 several target genes that negatively regulate germination in the embryo. ABI5 enhances the expression of phytochrome signaling genes PIF1, SOMNUS, GAI, and RGA, but also of ABA and gibberellic acid (GA) metabolic genes. Over time, weaker ABA-dependent responses eventually enable phyA-dependent germination, a distinct type of germination driven solely by embryonic growth.