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The efficiency of seven insecticides (beta-cyfluthrin, deltamethrin, formetanate hydrochloride, spinetoram, chlorfenapyr, imidacloprid and acetamiprid + etofenproxy) was evaluated in a field study conducted in two consecutive crop seasons against the garlic thrips (Thrips tabaci) in Caçador-SC. Two sprays of insecticides were carried out and evaluations were made at 3 and 7 days after each spray. The greatest reduction in thrips population was observed in treatments with spinetoram and formetanate hydrochloride followed by imidacloprid. Moreover, the insecticides beta-cyfluthrin, deltamethrin, chlorfenapyr and acetamiprid + etofenproxy were less effective in controlling thrips. The insecticides spinetoram and formetanate hydrochloride were the most efficient insecticides for the control of T. tabaci in garlic crop in Santa Catarina. A eficiência de sete inseticidas (beta-ciflutrina, deltametrina, cloridrato de formetanato, espinetoram, clorfenapir, imidacloprido e acetamiprido + etofenproxi) recomendados para o controle do tripes do alho (Thrips tabaci) foi avaliada em um estudo de campo conduzido em duas safras consecutivas no município de Caçador-SC. Foram realizadas duas aplicações dos inseticidas e as avaliações foram realizadas aos 3 e 7 dias após cada aplicação. A maior redução na população de tripes foi observada nos tratamentos com espinetoram e cloridrato de formetanato seguidos por imidacloprido. Já os inseticidas beta-ciflutrina, deltametrina, clorfenapir e acetamiprido + etofenproxi foram menos efetivos no controle dos tripes nas condições avaliadas. Os inseticidas espinetoram e cloridrato de formetanato foram os inseticidas mais eficientes para o controle de T. tabaci na cultura do alho em Santa Catarina.

Pallasite meteorites consist of olivine-metal mixtures and accessory minerals (chromite, sulfide, phosphide, phosphate, phosphoran olivine) and represent core-mantle interaction zones in early differentiated planetesimals. They can be linked to five distinct planetesimals, indicating that they are default differentiation products, but their formation modes (deep, shallow, and impact environments) and age are elusive. Using new trace element, Cr isotope, and previously published datasets, we re-some Main-group pallasites (low-MnO and high-FeO subgroups, e.g. Brenham and types respectively) as samples of core-mantle reaction zones. These meteorites host rounded olivine and near-solidus phosphate minerals, which record back-reaction of metal and silicate reservoirs during decreasing temperature after core formation and removal of primitive silicate melts. These phosphates form via late oxidation of, which is siderophile at high temperature but lithophile at low. Mn-Cr dates this event to 2.5 to 4 Myr after SolarSystem formation (range is model-dependent). Importantly, this is in agreement with Hf-W ages for very early metal-silicate (i.e. core-mantle), but also indicates rapid planetesimal cooling within a few million years. Near-solidus silico-phosphate melts probably formed before most known planetesimal crusts (eucrite and angrite meteorites) and are among the earliest evolved planetary silicates. Similar in non-Main-Group pallasites from other parent bodies also suggest that core-mantle reaction zones are generic, datable features of differentiation. The absence of near-solidus phosphates in common cluster pallasites suggests that these were quenched from high temperature and are mechanical mixtures, rather than samples of genuine core-mantle boundaries.

A mancha foliar, causada por Bipolaris maydis, é a principal doença de Panicum maximum. A seleção de genótipos resistentes é a melhor estratégia para o controle desta doença. Com o objetivo de identificar fontes de resistência de P. maximum à mancha foliar, 92 híbridos apomíticos, originários de cruzamentos das cultivares Tanzânia-1 e Mombaça, e outros três genótipos sexuais foram testados. Em blocos casualizados, com oito repetições cada, inocularam-se plantas com 30 dias de idade e, após 12 dias, a severidade da doença foi avaliada. Foram verificadas diferenças significativas (P

A utilização de gramíneas forrageiras em sistemas de integração lavoura-pecuária tem sido cada vez mais frequente no Brasil. Entretanto, alguns genótipos forrageiros podem hospedar fitonematoides, contribuindo para manter populações elevadas destes organismos no solo. Objetivando-se avaliar a reação de acessos e cultivares de Brachiaria spp. (B. ruziziensis, B. brizantha cvs. BRS Piatã e BRS Paiaguás, B. humidicola cv. BRS Tupi, e os genótipos B4 e HBGC 331) e Panicum maximum (cvs. Tanzânia-1 e Massai e os genótipos PM32, PM36, PM45 e PM46) à Pratylenchus brachyurus, realizou-se este trabalho. Como testemunhas utilizaram-se o milho BRS 2020 (suscetível) e milheto ADR 300 (resistente) à P. brachyurus. Os experimentos foram conduzidos em casa de vegetação, na Embrapa Gado de Corte, Campo Grande-MS, em blocos casualizados com sete repetições, de maio a setembro de 2011 e de março a maio de 2012. Utilizaram-se cinco plantas por vaso, que foram inoculadas com 1.000 espécimes de P. brachyurus. Após 90 dias, avaliaram-se as populações de nematoides na raiz e no solo, com a finalidade de obtenção da população final dos nematoides e o fator de reprodução (FR). Determinou-se ainda a reação dos genótipos em relação à porcentagem de redução do FR. Com exceção de B. humidicola cv. BRS Tupi, com FR de 0,98 e 0,44, no primeiro e segundo experimentos, respectivamente, todos os materiais avaliados permitiram a multiplicação do nematoide. Em relação à porcentagem de redução do FR, apenas a B. humidicola cv. BRS Tupi e o milheto ADR 300 foram classificados como moderadamente resistentes, com reduções de, no máximo 90,58% e 94,73%, no primeiro e segundo experimento, respectivamente. Entre os genótipos de forrageiras estudados a maioria mostrou-se suscetível à P. brachyurus, apesar de variação do grau de suscetibilidade entre os mesmos. Dessa forma, em áreas com histórico de presença de P. brachyurus, a B. humidicola cv. BRS Tupi pode ser indicada nos sistemas de integração e/ou em rotação de culturas, como estratégia de manejo para a redução populacional de P. brachyurus. The use of forage grass in integrated crop-livestock systems has been increasingly frequent in Brazil. However, some forage genotypes may host plant parasitic nematodes, contributing to the maintenance of large populations of these organisms in the soil. This study was conducted with the aim of evaluating the reaction of accessions and cultivars of Brachiaria spp. (B. ruziziensis, B. brizantha cvs. BRS Piatã and BRS Paiaguás, B. humidicola cv. BRS Tupi, and the genotypes B4 and HBGC 331) and Panicum maximum (cvs. Tanzânia-1 and Massai, and the genotypes PM32, PM36, PM45 and PM46) to Pratylenchus brachyurus. Corn BRS-2020 (susceptible) and millet ADR-300 (resistant) were used as controls. The experiments were conducted in a greenhouse at Embrapa Beef Cattle, Campo Grande-MS, in randomized blocks with seven replicates, from May to September 2011 and from March to May 2012. Five plants per pot were inoculated with 1,000 specimens of P. brachyurus. After 90 days, nematode populations in the roots and the soil were evaluated to obtain the final nematode population and the reproduction factor (RF). The reaction of genotypes in relation to the percentage of reduction in the RF was also assessed. Except for B. humidicola cv. BRS Tupi, which showed RF of 0.98 and 0.44 in the first and in the second experiments, respectively, all evaluated materials allowed the nematode multiplication. Regarding the percentage of reduction in the RF, only B. humidicola cv. BRS Tupi and millet ADR-300 were classified as moderately resistant, showing reductions of up to 90.58% and 94.73% in the first and in the second experiment, respectively. Most of the studied forage genotypes were susceptible to P. brachyurus, Even though the susceptibility degree varied among them. Thus, in areas with history of the presence of P. brachyurus, B. humidicola cv. BRS Tupi can be indicated for integrated and/or crop rotation system as a management strategy to reduce P. brachyurus population.

Objetivou-se avaliar a incidência de fungos e nematoides em sementes de Brachiaria sp. e Panicum maximum produzidas nos estados de Mato Grosso do Sul (MS), Mato Grosso (MT), Goiás (GO), Minas Gerais (MG) e São Paulo (SP). Os principais fungos encontrados nas sementes foram Bipolaris sp., Curvularia sp. e Phoma sp.. As menores incidências destes fungos foram encontradas nas sementes das cultivares BRS Piatã e Xaraés de Brachiaria brizantha e Brachiaria decumbens cv. Basilisk, oriundas dos estados de GO, MG e MS, respectivamente. As cultivares Marandu e BRS Piatã, provenientes das várias regiões, apresentaram elevada ocorrência de Aphelenchoides sp. e Ditylenchus sp.. Sementes da cultivar Humidicola, de Brachiaria humidicola, produzidas em MS e SP, não apresentaram associação com nematoides. As sementes de Panicum maximum cv. Massai e cv. Mombaça apresentaram maiores incidências de Bipolaris sp., Cladosporium sp., Curvularia sp., Fusarium sp. e Phoma sp., bem como de Aphelenchoides sp. e Ditylenchus sp., especialmente nas sementes produzidas em MT. Alguns dos patógenos encontrados são agentes causais de doenças de grande importância em forrageiras, a exemplo de Bipolaris sp., causando a mancha foliar do Panicum, de alta severidade em Tanzânia, proporcionando sérios comprometimentos da sustentabilidade das pastagens. This study aimed to assess the incidence of fungi and nematodes in Brachiaria sp. and Panicum maximum seeds produced in the Brazilian states of Mato Grosso do Sul (MS), Mato Grosso (MT), Goiás (GO), Minas Gerais (MG) and São Paulo (SP). The main fungi found in the seeds were Bipolaris sp., Curvularia sp. and Phoma sp.. The lowest incidence of these fungi was found for seeds of Brachiaria brizantha cultivars BRS Piatã and Xaraés, and Brachiaria decumbens cv. Basilisk, from the states of GO, MG and MS, respectively. The cultivars Marandu and BRS Piatã, from several regions, exhibited high occurrence of Aphelenchoides sp. and Ditylenchus sp.. Seeds of B. humidicola cultivar Humidicola, produced in MS and SP, did not show association with nematodes. The seeds of Panicum maximum cv. Massai and cv. Mombaça showed higher incidence of Bipolaris sp., Cladosporium sp., Curvularia sp., Fusarium sp. and Phoma sp., as well as Aphelenchoides sp. and Ditylenchus sp., especially for seeds produced in MT. Some of the detected pathogens are causative agents of diseases of major importance in forage plants, such as Bipolaris sp., causing leaf spot in Panicum, of high severity in Tanzânia, which provides serious compromising of the pasture sustainability.

Pallasites are mixtures of olivine and Fe-Ni metal,possibly formed near the core-mantle boundary of adifferentiated asteroid [1]. The distribution of trace elementsin pallasite olivine appears to reflect diffusion profiles [2]although complex structure has also been reported [3]. It hasrecently been shown experimentally [4] and in various naturalsamples [5] that Al and P diffuse very slowly in olivine andthese elements can preserve early distributions which areresistant to later thermal modification.To search for evidence of the early history of pallasiteolivine, we have used Laser-Ablation Inductively-Coupled-Plasma Mass-Spectrometry (LA-ICP-MS) to produce traceelementmaps of olivine from two pallasites: Brahin (withfragmental olivine) and Brenham (rounded olivine).Heterogeneous distributions are found over scales of ~100microns for Al and elements likely to associate with it incoupled substitutions. P is also heterogeneously distributed butis negatively correlated with or unrelated to Al. In Brahin,these distributions bear no relationship to the olivinemorphology; for Brenham, Al concentrations decrease at grainmargins but the interiors have complex distributions.Heterogeneous distributions of Al and P in pallasiteolivine provides some constraints on its residence time in ahigh-T environment. Taking the diffusion parameters for Si[6] as a proxy for the diffusion behaviour of these elements(since they reside in the same crystallographic site), at 1650 K(~OPX out for a fertile peridotite composition; [7]) thecharacteristic timescale for diffusion over 100 microns is ~1Ma. This represents an upper limit on the time between theestablishment of trace element systematics in olivine andformation of pallasites by mixing with metal.[1] Scott, E.R.D. (1977) GCA 41, 693. [2] Miyamoto, M.(1997) JGR 102, 21613. [3] Tomiyama T. & Huss G.R. (2006)LPSC 37, 2132. [4] Spandler C. & O’Neill H.St.C. (2010)CM&P 159, 791. [5] Milman-Barris M. et al. (2008) CM&P155, 739. [6] Dohmen R. et al. (2002) GRL 29, 2030.[7] Walter M. J. (2003) in Treatise on Geochemistry 2.08,363–394.

Using LA-ICP-MS, we have measured diffusion profiles for Co, and in some cases also been successful in obtaining Mn and Ni profiles, in olivine from the Brahin and Brenham pallasite meteorites and used them to constrain their relative cooling rates. 1. Introduction Pallasites are mixtures of Fe-Ni metal and olivine interpreted to have originated at the core-mantle boundary of a differentiated asteroid [1]. To constrain the environment of pallasite formation, there has been considerable to determine the cooling rates of these rocks, either using metallographic microstructures [2] or elemental zoning in olivine [3]. With development of rapid and more precise techniques for in situ trace element analysis of olivine [4] such as Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS), and recent improvements in the understanding of trace element diffusion in olivine [5], a reassessment of pallasite olivine trace element distributions arising from diffusive modification and otherprocesses is needed. As part of our broader study of pallasite olivine trace element [6] and Mn-Cr isotope [7] systematics, we have measured diffusion profiles for Mn, Co and Ni in two pallasites with contrasting petrographic textures: the Brahin pallasite (with fragmental olivine) and the Brenham pallasite (with rounded olivine). 2. Methods LA-ICP-MS has been used to measure diffusion profiles in olivine grains with a method similar to that described by [4]. The laser beam was shaped with a rectangular slit, giving a sampling area 100 microns long and several microns wide. This was scanned at a rate of 1 micron per second across olivine and perpendicularly into the grain boundary (Figure 1). Figure 1: Back-scattered electron image of Brenham olivine (grey) and sulfide (white) after laser ablation for ICP-MS. 3. Results We have obtained clear diffusion profiles for Co and in some cases for Mn and Ni as well (Figure 2). Ni concentrations in Brahin are steady or decrease very slightly at olivine margins, while in Brenham they do not change systematically from core to rim. Co decreases clearly within the outermost 10’s or 100’s of microns in olivine from both pallasites. The siderophile elements Ni and Co often show localized and correlated spikes in concentration, probably due to contamination by metal-filled cracks or microinclusions. Ni is affected by siderophile inclusions much more than Co and so it is more difficult to obtain a smooth profile for this element. EPSC Abstracts Vol. 6, EPSC-DPS2011-763, 2011 EPSC-DPS Joint Meeting 2011 c Author(s) 2011 Mn is homogeneous throughout olivine in Brahin, with possible slight increases in the outermost 10 microns (this is close to the spatial resolution of our technique). Mn in Brenham olivine clearly increases in concentration in the outer few 10’s of microns. Figure 2: Selected Mn, Co and Ni diffusion profiles for Brahin and Brenham olivine. 4. Discussion There is variation from scan to scan (e.g. Ni holding steady ordecreasing in Brahin, while being steady or increasing in Brenham) which probably represents apparent changes in concentration due to sectioning not being perpendicular to olivine margins, or could reflect slight variations in diffusivity with crystal orientation [4]. An important effect highlighted by [3] is that Fe-Mg profiles in different olivine grains from the same pallasite sometimes change concentrations in opposite directions. This indicates that the local environment, such as the particular mineral assemblage surrounding each olivine grain, may have some control over diffusive modification. That Mn has maintained homogeneity throughout olivine from Brahin and very nearly so in Brenham, while Ni and Co have not, indicates that the diffusivity of Mn is higher than Ni and Co under pallasitic conditions. This is consistent with work on natural terrestrial olivine [e.g. 8] which shows that Ni and Co diffuse at similar rates to Mn along the olivine c-axis but are slower along the b-axis. The development of diffusion-in profiles for Mn in Brenham olivine over 10’s of microns, while any similar effect in Brahin is much less developed, indicates that the cooling rate of Brenham was slower than Brahin and closure of Mn-diffusion occurred at lower temperature. This might seem qualitatively in agreement with the petrographic appearances of these meteorites, with Brahin having a brecciated texture while Brenham has rounded olivine. However, it has been shown that pallasite olivine morphology is unrelated to metallographic cooling rates [2], and that the required timescale for complete rounding of a coarse, fragmental olivine protolith is, at subsolidus conditions, too long to be relevant for pallasite petrogenesis [9]. The most recent data shows that pallasites cooled below 975 K at 2.5-18 K/Myr [2]. This span in cooling rates of less than a factor of 10 is consistent with the scales of Mn diffusion profiles observed in Brahin and Brenham, at ~10 microns (near detection limit) and 10’s of microns respectively. With a metallographic cooling rate for Brenham at 6.2 +/- 0.9 K/Myr [2], the subsolidus cooling rate of Brahin is likely near the upper end of the pallasite range (~18 K/Myr). 6. Summary and Conclusions Using LA-ICP-MS, we have obtained diffusion profiles for Co and in some cases also for Mn and Ni in olivine grains from the Brahin and Brenham pallasites. The relative lengths of diffusion profiles are consistent with current understanding of the relative diffusivities of these elements in olivine, and allow inference on the cooling rate of the Brahin pallasite. Acknowledgements We thank Charlotte Allen and Steve Eggins for LAICP- MS assistance and discussion of the data. This research was supported by an Australian National University PhD scholarship to Seann McKibbin. References [1] Scott, E. R. D. 1977, GCA 41, 349. [2] Yang J. et al. 2010 GCA 74, 4471. [3] Miyamoto M. 1997 JGR 102, E9, 21613. [4] Spandler C. and O’Neill H. 2010 CMP 159, 791. [5] Petry C. et al. 2004 GCA 68, 4179. [6] McKibbin et al. 2011 Goldschmidt Conference [7] McKibbin et al. 2011 MetSoc Conference [8] Qian Q. et al. 2010 Geology 38, 331. [9] Saiki K et al. 2003 MAPS 38, 427.

Vorgestellt wird ein lichtwellenleiterbasiertes Messsystem für die hochgenaue Formmessung, das die Messung in eingeschränkten Bauräumen wie Bohrungen oder an empfindlichen Bauteiloberflächen ermöglicht. Es basiert auf den Prinzip der kurzkohärenten Interferometrie und besteht aus einem faserbasierten und einem Freistrahl-Interferometer. Der Messaufbau wird beschrieben und es werden Anwendungsbeispiele für die hochgenaue faseroptische Formmessung vorgestellt wie Rundheitsprüfung in Mikrobohrung, Rundheits- und Rundlaufprüfung von Zahnrädern, Qualitätsprüfung in Ventilen und Düsenkörpern, Rundheits- und Rundlaufprüfung an strukturierten Wellen und an strukturierten Schleifscheiben.

Neuartige Produkte werden heutzutage immer effizienter und Ressourcen schonender ausgelegt. In vielen Industriebereichen (z.B. Luft- und Raumfahrt, sowie Automobil- und Medizintechnik) sind hierdurch Produktmerkmale entstanden, welche sich nur durch Mikro- und Nanotechnologien herstellen lassen. Damit wächst auch der Bedarf an messtechnischen Lösungen, welche die Qualität, Geometrie und Funktionalität von diesen Produkten erfassen müssen.