46 research outputs found
Multi-environment field testing for identification and validation of genetic resistance to Botrytis cinerea causing Botrytis grey mold in chickpea (Cicer arietinum L.)
Botrytis grey mould (BGM), caused by Botrytis cinerea Pers. Ex. Fr., is a destructive foliar disease of chickpea (Cicer arietinum L.) worldwide. Disease management through host-plant resistance is the most effective and economic option to manage this disease. The objective of this study was to identify new sources of resistance to BGM, validate their stability across environments and determine the magnitude of G Ă E interaction. One hundred and nine chickpea genotypes with moderate levels of resistance (BGM severity â€5.0 on a 1â9 scale) were selected from the preliminary evaluation of 412 genotypes including germplasm and breeding lines under controlled environmental conditions in 2004â2005 at the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, India. In order to validate resistance stability, an âInternational Botrytis Grey Mould Nurseryâ (IBGMN) was constituted with 25 genotypes and tested in multi-environments for BGM resistance at two locations (Gurdaspur and Pantnagar) in India for 4 years and two locations (Tarahara and Rampur) in Nepal for 3 years. Additive main effects and multiplicative interaction (AMMI) analysis showed significant genotype (G), environment (E) and G Ă E interaction (p < 0.0001) with largest contribution by environment (47.36%). The first two principal component axes were significant, and contributed 48.21% to the total G Ă E interaction. The AMMI biplot analysis allowed the selection of five genotypes ICCV 96859, ICCV 96853, ICCV 05604, ICCV 96852 and ICCV 05605 with low BGM severity (between 3.7 and 4.7 on 1â9 scale) and moderate stability. Genotype ICCV 96859 having least disease severity and moderate stability could be highlighted and exploited in chickpea resistance breeding programme
Search for leptonic decays of D0 mesons
We search for the flavor-changing neutral current decays D0\to mu+mu- and
D0\to e+e-, and for the lepton-flavor violating decays D0\to e\pm mu\mp using
660 fb^-1 of data collected with the Belle detector at the KEKB
asymmetric-energy e+e- collider. We find no evidence for any of these decays.
We obtain significantly improved upper limits on the branching fractions:
B(D0\to mu+mu-)<1.4x10-7, B(D0\to e+e-)<7.9x10-8, and B(D0\to e+mu-)+B(D0\to
mu+e-)<2.6x10-7 at 90% confidence level.Comment: 6 pages, 3 figure
Search for B -> h(*) nu nubar Decays at Belle
We present a search for the rare decays B -> h(*) nu nubar, where h(*) stands
for a light meson. A data sample of 535 million BBbar pairs collected with the
Belle detector at the KEKB e+e- collider is used. Signal candidates are
required to have an accompanying B meson fully reconstructed in a hadronic mode
and signal-side particles consistent with a single h(*) meson. No significant
signal is observed and we set upper limits on the branching fractions at 90%
confidence level. The limits on B0 -> K*0 nu nubar and B+ -> K+ nu nubar decays
are more stringent than the previous constraints, while the first searches for
B0 -> K0 nu nubar, pi0 nu nubar, rho0 nu nubar, phi nu nubar and B+ -> K*+ nu
nubar, rho+ nu nubar are reported.Comment: 6 pages, 2 figures, submit to PR
First Observation of Radiative B^0 -> \phi K^0 \gamma Decays and Measurements of Their Time-Dependent CP Violation
We report the first observation of the radiative decay B^0 -> \phi K^0 \gamma
using a data sample of 772 x 10^6 B B-bar pairs collected at the \Upsilon(4S)
resonance with the Belle detector at the KEKB asymmetric-energy e^+e^-
collider. We observe a signal of 37+/-8 events with a significance of 5.4
standard deviations including systematic uncertainties. The measured branching
fraction is , where the uncertainties are statistical and systematic, respectively.
We also report the first measurements of time-dependent CP violation
parameters: and . Furthermore, we measure , and find that the signal is concentrated in
the M_{\phi K} mass region near threshold.Comment: 6 pages, 3 figures, Modified version is to be published in PRD(RC
Measurement of the Decay B_s^0 -> D_s^- pi^+ and Evidence for B_s^0 -> D_s^{+/-} K^{-/+} in e+e- Annihilation at sqrt(s)~10.87 GeV
We have studied Bs0 -> Ds- pi+ and Bs0 -> Ds^(-/+) K^(+/-) decays using 23.6
/fb of data collected at the Upsilon(5S) resonance with the Belle detector at
the KEKB e+e- collider.
This highly pure Bs0 -> Ds- pi+ sample is used to measure the branching
fraction, BR(Bs0 -> Ds- pi+)=[3.67 +0.35,-0.33}(stat.) +0.43,-0.42(syst.)
+-0.49(f_s)] x 10^{-3} (f_s=N(Bs(*) Bs(*)bar)/N(b\bar b)) and the fractions of
Bs0 event types at the Upsilon(5S) energy, {in particular N(Bs*
Bs*bar}/N(N(Bs(*) Bs(*)bar)=(90.1 +3.8,-4.0 +-0.2)%. We also determine the
masses M(Bs0)=(5364.4 +-1.3 +-0.7) MeV/c^2 and M(Bs*)=(5416.4 +-0.4 +-0.5)
MeV/c^2. In addition, we observe Bs0 -> Ds^(-/+) K^(+/-) decays with a
significance of 3.5\sigma and measure BR(Bs0 -> Ds^(-/+) K^(+/-))=[2.4
+1.2,-1.0(stat.) +-0.3(syst.) +-0.3(f_s)] x 10^{-4}.Comment: 5 pages, 4 figures, accepted by PR
First observation of and
We report first observations of and . The results are obtained from 121.4 fb^{-1} of data collected at
the resonance with the Belle detector at the KEKB
collider. We obtain the branching fractions Br(B_s^0\to J/\psi\eta)= [5.10\pm
0.50(stat.)\pm 0.25(syst.)^{+1.14}_{-0.79}(N_{B_s^(*)\bar B_s^(*))] \times
10^{-4}, and Br(B_s^0\to J/\psi\eta')=[3.71\pm 0.61(stat.)\pm
0.18(syst.)^{+0.83}_{-0.57}(N_{B_s^(*)\bar B_s^(*))] \times 10^{-4}. The ratio
of the two branching fractions is measured to be .Comment: 5 pages, 3 figures, 2 table