Effect of population and spacing on soybean potential yield during ontogeny

O objetivo deste trabalho foi verificar o efeito da redução do espaçamento entre linhas, de populações de plantas e de níveis de fertilidade do solo no potencial de rendimento da soja, em três estádios fenológicos. O trabalho foi conduzido na Estação Experimental Agronômica da Universidade Federal do Rio Grande do Sul, na safra 1996/97, em solo Argissolo Vermelho Distrófico típico. O delineamento experimental foi blocos ao acaso com parcelas subsubdivididas e quatro repetições. Os tratamentos constaram de três níveis de fertilidade do solo (sem adubação, adubação recomendada e duas vezes a adubação recomendada), duas populações (30 e 40 plantas m-2) e dois espaçamentos entre linhas (20 e 40 cm). A cultivar testada foi FT Saray (precoce) sob semeadura direta. O potencial de rendimento médio foi de 15.007 kg ha-1 em R2, 10.282 kg ha-1 em R5 e 5.330 kg ha-1 em R8 (maturação). Tanto a variação na população de plantas como no espaçamento entre linhas afetaram o potencial de rendimento da soja. A população de 40 plantas m-2 foi superior a 30 plantas m-2 em R5, mas tal vantagem não se manteve até a maturação, pois, nesse estádio, não houve diferença significativa entre populações. Com 20 cm de espaçamento o potencial de rendimento foi maior que com 40 cm a partir de R5, resultando em maior rendimento em R8.The objective of this study was to evaluate the effects of the row spacing reduction, plant populations and soil fertility on soybean potential yield at three stages of development. The experiment was performed at the Estação Experimental Agronômica of Universidade Federal do Rio Grande do Sul, in Eldorado do Sul, Rio Grande do Sul State, Brazil, in the 1996/97 growing season, in a Rhodic Paleudult soil . The experimental design was a split split-plot randomized complete block, with four replicates. Treatments were tested at three soil fertility levels (without fertilization, the recommended fertilization and twice the recommended fertilization), two plant populations (30 and 40 plants m-2) and two row spacing (20 and 40 cm). The cultivar tested was FT-Saray (early), in no-till. Mean potential yields were 15.007 kg ha-1 in R2, 10.282 kg ha-1 in R5 and 5.330 kg ha-1 in R8 (maturity). Plant populations as well as row spacing affected the soybean potential yield. The population of 40 plants m-2 was greater than the 30 plants m-2 in R5 but this advantage was not observed at maturity, because at this stage there was no difference between populations. With 20 cm rows the potential yield was greater than with 40 cm in R5, resulting in higher yield in R8

Postemergence broadleaf herbicide selectivity in cassava

O principal problema de manejo na cultura da mandioca envolve a interferência exercida pelas plantas daninhas, as quais ocasionam elevadas reduções no rendimento de raízes. A inexistência de herbicidas de pós-emergência, toma o controle possível apenas pela aplicação de herbicidas de pré-emergência ou através de capinas manuais. O objetivo do experimento foi avaliar a seletividade de herbicidas com ação latifolicida aplicados em pós-emergência da cultura da mandioca. Para isso, foi conduzido um experimento na Faculdade de Agronomia da Universidade Federal do Rio Grande do Sul, em vasos com capacidade de 10 litros, nos quais foram plantadas quatro manivas. O delineamento experimental utilizado foi completamente casualizado, com cinco repetições. Os herbicidas utilizados foram: acifluorfen, bentazon, fomesafen, byspiribac, chlorimuron, imazethapyr, nicosulfuron e linuron. As variáveis avaliadas foram a fitotoxicidade dos herbicidas aos 4,8, 14 e 28 dias após aplicação dos tratamentos (DAT) e a produção de fito massa da parte aérea aos 14 e 28 DAT. O herbicida nicosulfuron apresentou seletividade à mandioca quando aplicado no estádio inicial de seu desenvolvimento, destacando-se dentre os tratamentos em produção de fitomassa, constituindo-se em opção promissora para controlar ervas dicotiledôneas nesta cultura. The main management problem in the cassava crop in due to interference by weeds, where they bring about root yield reductions. Inexistence of selective postemergence herbicides, makes weed control only possible with preemergence herbicides or through hand hoeing. The objective of this research was to evaluate broadleaf herbicide selectivity when applied postemerg.ence on cassava plants. An experiment was carried out at University of Rio Grande do Sul, Brazil, using 10-liter volume pots, where four cassava cuttings were planted. The experimental design used was a completely randomized one, with five replications. The tested herbicides were: acifluorfen, bentazon, fomesafen, byspiribac, chlorimuron, imazethapyr, nicosulfuron and linuron. The variables evaluated were herbicide injury at 4, 8, 14 and 28 days after treatment application (DAT), and shoot dry weight at 14 and 18 DAT. Nicosulfuron was selective for cassava when applied at an early growth stage, significa~tly different from the other treatments as far as biomass production is concemed, constituting a promising option for selective broadleafweed control in this crop.

SOYBEAN VARIETIES DIFFER IN THE VELOCITY AND CAPACITY OF WATER ABSORPTION

The seeds resume the metabolic process by imbibition, which supplies the necessity of water and promote the beginning of germination. The present study, performed at the Faculdade de Agronomia of Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, in the 1993 year, was undertaken to evaluate the behavior of soybean cultivars in relation to maximum capacity and velocity of water absorption, measured in hourly intervals, for eight consecutive hours, in total imbibition in water. Seeds of 17 cultivars with diameter larger than 6.3 mm and with absence of cracks when observed with binocular in the seed coat were utilized. The cultivar RS 6 Guassupí showed the highest velocity and capacity of water absorption. FT Abyara and Bragg showed the smallest velocity and capacity of water absorption in the first hours of imbibition, but in the last hours RS 7 Jacuí was the one which presented the smallest water absorption capacity. The conclusion from this study is that the cultivars tested have some distinct caracteristic that allowed for the diferences in the water imbibition velocity and total capacity of water absorption that was not detected in this research.As sementes iniciam a retomada dos processos metabólicos a partir da embebição. Esta supre a necessidade de água para reduzir a resistência mecânica do tegumento, hidratar o embrião e cotilédones, induzindo o embrião a ativar enzimas que aceleram o processo de quebra de materiais de reserva usados para dar início à germinação da semente. Este experimento, realizado na Faculdade de Agronomia da Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, no ano de 1993, objetivou avaliar o comportamento de cultivares de soja quanto à capacidade máxima e velocidade de absorção de água, em intervalos de hora, até oito horas consecutivas, quando em embebição total em água. Foram utilizadas sementes de 17 cultivares com tamanho uniformizado para diâmetro maior que 6,3 mm e ausência de rachaduras no tegumento quando observadas através de lupa. A cultivar RS 6 Guassupí apresentou a maior velocidade e capacidade total de absorção de água. FT Abyara e Bragg apresentaram a menor velocidade e menor capacidade total de absorção nas primeiras horas de embebição, mas nas ultimas horas foi a RS 7 Jacuí que apresentou a menor capacidade de absorção. Este estudo permitiu concluir que existem diferenças na velocidade e na capacidade total de absorver água entre as cultivares testadas, devido a alguma característica distinta entre elas, que não foi investigada neste trabalho e que torna suas sementes mais ou menos permeáveis a água

Potencial de rendimento da soja em razão da disponibilidade de fósforo no solo e dos espaçamentos

The experiment was performed during the 1994/95 growing season at the EEA/UFRGS, in Eldorado do Sul, RS, Brazil, in a dark red Podzolic soil (Rhodic Paleudult). The objective was to evaluate the soybean potential yield at the growth stages R2 (flowering), R5 (beginning of pod filling) and R8 (maturity). The treatments were arranged in subplots in a randomized complete block design, and consisted of two soil P levels (3 and 15 ppm), and two row spacings (20 and 40 cm). The early, determinate cultivar OCEPAR 14 was used. On the average of the treatments, potential yield in R2 was of 18 t/ha and of 10 t/ha in R5, and the final yield, in R8 of 4.6 t/ha. The treatment of 15 ppm of P reached greater potential yield in the three growth stages, due to less flower and pod abortion. The row spacing of 20 cm showed greater potential yield at the growth stages evaluated, but the percentage of yield reduction due to flower and pod abortion were similar.O objetivo deste trabalho foi avaliar o potencial produtivo de grãos da soja nos estádios fenológicos R2 (florescimento), R5 (início de enchimento de grãos) e R8 (maturação). O experimento foi conduzido durante o ano agrícola 1994/95 na EEA/UFRGS, Eldorado do Sul, RS, em solo Podzólico Vermelho-Escuro (Paleudult). O delineamento utilizado foi o de blocos casualizados, com quatro repetições, com os tratamentos arranjados em parcelas subdivididas. Os tratamentos originaram-se da combinação de dois níveis de P no solo (3 e 15 ppm), e dois espaçamentos entre linhas (20 e 40 cm). Foi utilizada a cultivar precoce, determinada, OCEPAR 14. Na média dos tratamentos, o potencial de rendimento alcançado em R2 foi de 18 t/ha e de 10 t/ha em R5, sendo o rendimento obtido em R8 de 4,6 t/ha. O tratamento com 15 ppm de P apresentou maior potencial de rendimento, nos três estádios fenológicos, em decorrência do menor aborto de flores e de legumes. O espaçamento de 20 cm entre linhas apresentou maior potencial que o de 40 cm nos três estádios fenológicos avaliados, mas os valores percentuais de diminuição do rendimento pelo aborto de flores e de legumes foram similares

The Type Ic Supernova 1994I in M51: Detection of Helium and Spectral Evolution

We present a series of spectra of SN 1994I in M51, starting 1 week prior to maximum brightness. The nebular phase began about 2 months after the explosion; together with the rapid decline of the optical light, this suggests that the ejected mass was small. Although lines of He I in the optical region are weak or absent, consistent with the Type Ic classification, we detect strong He I λ10830 absorption during the first month past maximum. Thus, if SN 1994I is a typical Type Ic supernova, the atmospheres of these objects cannot be completely devoid of helium. The emission-line widths are smaller than predicted by the model of Nomoto and coworkers, in which the iron core of a low-mass carbon-oxygen star collapses. They are, however, larger than in Type Ib supernovae

Fluorescence of pterin, 6-formylpterin, 6-carboxypterin and folic acid in aqueous solution: pH effects

Steady-state and time-resolved studies have been performed on four compounds of the pterin family (pterin, 6-carboxypterin, 6-formylpterin and folic acid) in aqueous solution, using the single photon counting technique. The fluorescence characteristics (spectra, quantum yields, lifetimes) of these compounds and their dependence on the pH have been investigated. Most pterins can exist in two acid–base forms over the pH range between 3 and 13. Emission spectra and excitation spectra were obtained for both forms of each compound studied. Fluorescence quantum yields (ΦF) in acidic and basic media were measured. The ΦF of folic acid (F) was analysed as a function of pH. Dynamic quenching by OH⁻ was observed and the corresponding bimolecular rate constants for quenching of fluorescence (kq) were calculated. The reported values for kq; (M⁻¹ s⁻¹) are 3.6 × 10⁹, 1.9 × 10⁹ and 1.1 × 10¹⁰ M⁻¹ s⁻¹ for pterin, 6-carboxypterin and 6-formylpterin, respectively.Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicada

Report and preliminary results of SONNE cruise SO175, Miami - Bremerhaven, 12.11 - 30.12.2003 : (GAP, Gibraltar Arc Processes)

Expedition SO175 using FS Sonne aimed for a multidisciplinerary geoscientific approach with an international group of researchers. Methods covered the entire span from geophysical data acquisition (seafloor mapping, echography, seismic reflection), sediment coring at sites of active fluid venting, in situ heat flow measurements across the entire length of the Gibraltar thrust wedge, the deformation front, landslide bodies, and mud volcanoes, and finally the deployment of a long-term pore pressure probe. Video-supported operations helped to identify fluid vent sites, regions with tectonic activity, and other attractive high priority targets. Qualitative and quantitative examinations took place on board and are continued on land with respect to pore pressure variation, geomicrobiology, sediment- and fluid mobilization, geochemical processes, faunal assemblages (e.g. cold water corals), and gas hydrates (flammable methane-ice-crystals). Main focus of the expedition has been a better understanding of interaction between dynamic processes in a seismically active region region with slow plate convergence. In the context of earthquake nucleation and subduction zone processes, the SO175 research programme had a variety of goals, such as: • To test the frictional behaviour of the abyssal plain sediments. • To explore the temperature field of the 1755 thrust earthquake event via heat flow measurements. • To assess the role of fluid venting and gas hydrate processes control slope stability and mud volcanic activity along the Iberian continental margin. • To measure isotope geochemistry of pore waters and carbonates of deep fluids. • To quantify microbial activity in Gibraltar wedge sediments. • To test whether microseismicity in the area corresponds to in situ pore pressure changes. • To find out if enhanced heat flow max be indicative of active subduction. Initial tentative results during the cruise suggest that there is a component of active thrusting at the base of the wedge, as attested by heat flow data. Based on mostly geochemical evidence, mud volcanism was found less active than previously assumed. Highlights from post-cruise research include the successful deployment of the long-term station and high frictional resistance of all incoming sediment on the three abyssal plains

IMPROVE: Advanced displays and interaction techniques for collaborative design review

In this paper we present evaluation results of an innovative application designed to make collaborative design review in the architectural and automotive domain more effective. Within IMPROVE, a European research project in the area of advanced displays, we are combining high resolution multi-tile displays, TabletPCs and head-mounted displays with innovative 2D and 3D Interaction Paradigms to better support collaborative mobile mixed reality design reviews. Our research and development is motivated by application scenarios in the automotive domain involving FIAT Elasis from Naples, Italy and in the architectural domain involving Page/Park architects from Glasgow, Scotland. User evaluation took place at Glasgow (UK), Naples (ITA) and Darmstadt (GER), where we tested the integrated IMPROVE prototype application. The tests were conducted based on several heuristics such as ergonomics and psychomotorial factors and they were conducted based on guidelines recommended by ISO 9241 to verify whether the developed interfaces were suitable for the applications scenarios. Evaluation results show that there is a strong demand for more interactive design review systems, allowing users greater flexibility and greater choice of input and visualization modalities as well as their combination

IMPROVE: collaborative design review in mobile mixed reality

In this paper we introduce an innovative application designed to make collaborative design review in the architectural and automotive domain more effective. For this purpose we present a system architecture which combines variety of visualization displays such as high resolution multi-tile displays, TabletPCs and head-mounted displays with innovative 2D and 3D Interaction Paradigms to better support collaborative mobile mixed reality design reviews. Our research and development is motivated by two use scenarios: automotive and architectural design review involving real users from Page\Park architects and FIAT Elasis. Our activities are supported by the EU IST project IMPROVE aimed at developing advanced display techniques, fostering activities in the areas of: optical see-through HMD development using unique OLED technology, marker-less optical tracking, mixed reality rendering, image calibration for large tiled displays, collaborative tablet-based and projection wall oriented interaction and stereoscopic video streaming for mobile users. The paper gives an overview of the hardware and software developments within IMPROVE and concludes with results from first user tests

Human pre-valvular endocardial cells derived from pluripotent stem cells recapitulate cardiac pathophysiological valvulogenesis

Genetically modified mice have advanced our understanding of valve development and disease. Yet, human pathophysiological valvulogenesis remains poorly understood. Here we report that, by combining single cell sequencing and in vivo approaches, a population of human pre-valvular endocardial cells (HPVCs) can be derived from pluripotent stem cells. HPVCs express gene patterns conforming to the E9.0 mouse atrio-ventricular canal (AVC) endocardium signature. HPVCs treated with BMP2, cultured on mouse AVC cushions, or transplanted into the AVC of embryonic mouse hearts, undergo endothelial-to-mesenchymal transition and express markers of valve interstitial cells of different valvular layers, demonstrating cell specificity. Extending this model to patient-specific induced pluripotent stem cells recapitulates features of mitral valve prolapse and identified dysregulation of the SHH pathway. Concurrently increased ECM secretion can be rescued by SHH inhibition, thus providing a putative therapeutic target. In summary, we report a human cell model of valvulogenesis that faithfully recapitulates valve disease in a dish.We thank the Leducq Fondation for supporting Tui Neri, and funding this research under the framework of the MITRAL network and for generously awarding us for the equipment of our cell imaging facility in the frame of their program “Equipement de Recherche et Plateformes Technologiques” (ERPT to M.P.), the Genopole at Evry and the Fondation de la recherche Medicale (grant DEQ20100318280) for supporting the laboratory of Michel Puceat. Part of this work in South Carolina University was conducted in a facility constructed with support from the National Institutes of Health, Grant Number C06 RR018823 from the Extramural Research Facilities Program of the National Center for Research Resources. Other funding sources: National Heart Lung and Blood Institute: RO1-HL33756 (R.R.M.), COBRE P20RR016434–07 (R.R.M., R.A. N.), P20RR016434–09S1 (R.R.M. and R.A.N.); American Heart Association: 11SDG5270006 (R.A.N.); National Science Foundation: EPS-0902795 (R.R.M. and R.A. N.); American Heart Association: 10SDG2630130 (A.C.Z.), NIH: P01HD032573 (A.C. Z.), NIH: U54 HL108460 (A.C.Z), NCATS: UL1TR000100 (A.C.Z.); EH was supported by a fellowship of the Ministere de la recherche et de l’éducation in France.TM-M was supported by a fellowship from the Fondation Foulon Delalande and the Leducq Foundation. P.v.V. was sponsored by a UC San Diego Cardiovascular Scholarship Award and a Postdoctoral Fellowship from the California Institute for Regenerative Medicine (CIRM) Interdisciplinary Stem Cell Training Program II. S.M.E. was funded by a grant from the National Heart, Lung, and Blood Institute (HL-117649). A.T. is supported by the National Heart, Lung, and Blood Institute (R01-HL134664).S