Ocorrência do vírus do endurecimento dos frutos do maracujazeiro no Estado do Pará.

bitstream/item/59293/1/CPATU-ComTec101.pd

Long-lasting systematic roguing for effective management of CABMV in passion flower orchards through maintenance of separated plants.

In Brazil, passion flower is grown across almost the entire country. The predominant disease of the passion flower cropis passion fruit woodiness, caused by the potyvirus cowpea aphid-borne mosaic virus (CABMV), and transmitted byaphids in a nonpersistent manner. The disease reduces the useful life of the orchard from 36 months to approximately18 months. Up to now, there has not been an efficient method for disease management. The aim of this work was toevaluate the efficiency of systematic roguing of diseased plants through weekly inspections, for disease management inthe field. The latent and incubation periods of CABMV in passion flower vines were determined in order to optimizeroguing efficiency. Passion fruit plants inoculated with CABMV started to act as sources of inoculum from 3 days afterinoculation (DAI), and the symptoms were expressed, on average, at 8 DAI. Five field experiments, conducted in thestates of S~ao Paulo and Bahia, Brazil, demonstrated that systematic roguing of diseased plants was significantly efficientfor managing passion fruit woodiness disease. In order to facilitate identification and subsequent removal of theinfected plants, they need to be grown separately. This cultural practice can be recommended for managing passionfruit woodiness disease, provided it is applied on a regional scale by all passion fruit growers. The development ofsome pilot plantings for the application of roguing in a passion flower-producing region is recommended to validatethe use of this technique for managing passion fruit woodiness disease

Evaluation of the morphologic, pollen viability and germination in progeny of the first backcross generation of passionfruit.

Brazil is considered the main center of the genetic diversity and greatest worldwide producer of passionfruit. This fruit is severely attacked by many phytosanitary problems, specially by the passionfruit woodiness virus which leads to severe losses in yield. Wild species of Passifloraare valuable sources of genetic resistance to this disease

Avaliação de acessos de maracujazeiro-azedo com base nas características físicas de frutos.

Pesquisas com o Banco de Germoplasma de maracujazeiro-azedo são cada vez mais importantes e fundamentais para subsidiar atividades que visam à conservação da variabilidade genética e a busca por genótipos promissores. Entre os grandes desafios da pesquisa em maracujazeiro, o estudo da variabilidade genética é uma atividade de grande relevância para o melhoramento genético. Através desse conhecimento, é possível identificar e selecionar genótipos com características de interesse, como alta produtividade e fontes de resistências as principais doenças, para serem utilizados em programas de melhoramento. Sendo assim, é essencial uma efetiva caracterização agronômica e avaliação da variabilidade genética presente no gênero Passiflora

Avaliação da resistência genética de genótipos de maracujazeiro ao Cowpea aphid borne mosaic virus.

Apesar de a passicultura ter elevada importância econômica para a fruticultura brasileira, tal cultura vem enfrentando vários problemas fitossanitários, entre os quais o endurecimento dos frutos causado pelo Cowpea aphid borne mosaic virus (CABMV)

Search for right-handed W bosons in top quark decay

We present a measurement of the fraction f+ of right-handed W bosons produced in top quark decays, based on a candidate sample of $t\bar{t}$ events in the lepton+jets decay mode. These data correspond to an integrated luminosity of 230pb^-1, collected by the DO detector at the Fermilab Tevatron $p\bar{p}$ Collider at sqrt(s)=1.96 TeV. We use a constrained fit to reconstruct the kinematics of the $t\bar{t}$ and decay products, which allows for the measurement of the leptonic decay angle $\theta^*$ for each event. By comparing the $\cos\theta^*$ distribution from the data with those for the expected background and signal for various values of f+, we find f+=0.00+-0.13(stat)+-0.07(syst). This measurement is consistent with the standard model prediction of f+=3.6x10^-4.Comment: Submitted to Physical Review D Rapid Communications 7 pages, 3 figure

Measurement of Semileptonic Branching Fractions of B Mesons to Narrow D** States

Using the data accumulated in 2002-2004 with the DO detector in proton-antiproton collisions at the Fermilab Tevatron collider with centre-of-mass energy 1.96 TeV, the branching fractions of the decays B -> \bar{D}_1^0(2420) \mu^+ \nu_\mu X and B -> \bar{D}_2^{*0}(2460) \mu^+ \nu_\mu X and their ratio have been measured: BR(\bar{b}->B) \cdot BR(B-> \bar{D}_1^0 \mu^+ \nu_\mu X) \cdot BR(\bar{D}_1^0 -> D*- pi+) = (0.087+-0.007(stat)+-0.014(syst))%; BR(\bar{b}->B)\cdot BR(B->D_2^{*0} \mu^+ \nu_\mu X) \cdot BR(\bar{D}_2^{*0} -> D*- \pi^+) = (0.035+-0.007(stat)+-0.008(syst))%; and (BR(B -> \bar{D}_2^{*0} \mu^+ \nu_\mu X)BR(D2*0->D*- pi+)) / (BR(B -> \bar{D}_1^{0} \mu^+ \nu_\mu X)\cdot BR(\bar{D}_1^{0}->D*- \pi^+)) = 0.39+-0.09(stat)+-0.12(syst), where the charge conjugated states are always implied.Comment: submitted to Phys. Rev. Let

Measurement of the Lifetime Difference in the B_s^0 System

We present a study of the decay B_s^0 -> J/psi phi We obtain the CP-odd fraction in the final state at time zero, R_perp = 0.16 +/- 0.10 (stat) +/- 0.02 (syst), the average lifetime of the (B_s, B_sbar) system, tau (B_s^0) =1.39^{+0.13}_{-0.16} (stat) ^{+0.01}_{-0.02} (syst) ps, and the relative width difference between the heavy and light mass eigenstates, Delta Gamma/Gamma = (Gamma_L - Gamma_H)/Gamma =0.24^{+0.28}_{-0.38} (stat) ^{+0.03}_{-0.04} (syst). With the additional constraint from the world average of the B_s^0$lifetime measurements using semileptonic decays, we find tau (B_s^0)= 1.39 +/- 0.06 ~ps and Delta Gamma/\Gamma = 0.25^{+0.14}_{-0.15}. For the ratio of the B_s^0 and B^0 lifetimes we obtain tau(B_s^0)/tau(B^0)} = 0.91 +/- 0.09 (stat) +/- 0.003 (syst).Comment: submitted to Phys. Rev. Lett. FERMILAB-PUB-05-324-

A search for W bb and W Higgs production in ppbar collisions at sqrt(s)=1.96 TeV

We present a search for W b \bar{b} production in p \bar{p} collisions at sqrt{s}=1.96 TeV in events containing one electron, an imbalance in transverse momentum, and two b-tagged jets. Using 174 pb-1 of integrated luminosity accumulated by the D0 experiment at the Fermilab Tevatron collider, and the standard-model description of such events, we set a 95% C.L. upper limit on W b \bar{b}$production of 6.6 pb for b quarks with transverse momenta p_T^b > 20 GeV and b \bar{b} separation in pseudorapidity-azimuth space Delta R_bb > 0.75. Restricting the search to optimized b \bar{b} mass intervals provides upper limits on$WH$production of 9.0$-$12.2 pb, for Higgs-boson masses of 105$-$135 GeV.Comment: 7 pages, 4 figures, 1 table, submitted to Physical Review Letter