Genetic diversity in Indian isolates of Fusarium oxysporum f. sp. ciceris, chickpea wilt pathogen

Forty-eight isolates of FOC collected from different chickpea growing regions in India were evaluated for genetic variations using amplified fragment length polymorphism (AFLP). Out of 48 isolates, 41 were found pathogenic and seven non-pathogenic. Pathogenic isolates differ in their virulence however; there was no apparent correlation between geographical origin and virulence of the isolates. The genetic variation was evaluated by the AFLP analysis. A total 339 fragments were scored following selective amplification with five EcoR1 and Mse1 primer combinations E-TC/M-CAT, E-TC/M-CAC, E-AC/M-CAG, E-TA/MCAG, E-TA/M-CAG, out of which 331 fragments were polymorphic. UPGMA cluster analysis and principle coordinate analysis distinctly classified 48 isolates into two major groups; pathogenic and non-pathogenic. The pathogenic isolates could be further clustered into six major groups at 0.77 genetic similarities. Region specific grouping was observed with in few isolates. The results of the present study provide evidence of the high discriminatory power of AFLP analysis, suggesting the applicability of this method to the molecular characterization of Fusarium oxysporum f.sp. ciceris

Mass-screening techniques for the early selection of disease resistance in chickpea (Cicer arietinum)

Host plant resistance offers the most sustainable and effective disease management option to combat diseases in chickpea. In this chapter, we briefly describe the distribution, economic importance and symptoms of the most important diseases of chickpea including Ascochyta blight, Botrytis grey mould, Fusarium wilt, dry root rot, collar rot, black root rot and stem rot. Screening methods developed by different research institutes to select germplasm and breeding lines resistant against these diseases are reviewed. A variety of field, greenhouse, growth room and laboratory screening techniques along with disease rating scale to facilitate the identification of resistant breeding material are discussed in detail. Coloured illustrations for each technique are provided as well as extensive lists of available resistant sources against all diseases. For the selection of sources of resistance to various diseases in chickpea, and for breeding high yielding cultivars with improved levels of resistance, this chapter describes current techniques for the simultaneous screening of a large number of chickpea plants

A rotating three component perfect fluid source and its junction with empty space-time

The Kerr solution for empty space-time is presented in an ellipsoidally symmetric coordinate system and it is used to produce generalised ellipsoidal metrics appropriate for the generation of rotating interior solutions of Einstein's equations. It is shown that these solutions are the familiar static perfect fluid cases commonly derived in curvature coordinates but now endowed with rotation. The resulting solutions are also discussed in the context of T-solutions of Einstein's equations and the vacuum T-solution outside a rotating source is presented. The interior source for these solutions is shown not to be a perfect fluid but rather an anisotropic three component perfect fluid for which the energy momentum tensor is derived. The Schwarzschild interior solution is given as an example of the approach.Comment: 14 page

Shell Corrections of Superheavy Nuclei in Self-Consistent Calculations

Shell corrections to the nuclear binding energy as a measure of shell effects in superheavy nuclei are studied within the self-consistent Skyrme-Hartree-Fock and Relativistic Mean-Field theories. Due to the presence of low-lying proton continuum resulting in a free particle gas, special attention is paid to the treatment of single-particle level density. To cure the pathological behavior of shell correction around the particle threshold, the method based on the Green's function approach has been adopted. It is demonstrated that for the vast majority of Skyrme interactions commonly employed in nuclear structure calculations, the strongest shell stabilization appears for Z=124, and 126, and for N=184. On the other hand, in the relativistic approaches the strongest spherical shell effect appears systematically for Z=120 and N=172. This difference has probably its roots in the spin-orbit potential. We have also shown that, in contrast to shell corrections which are fairly independent on the force, macroscopic energies extracted from self-consistent calculations strongly depend on the actual force parametrisation used. That is, the A and Z dependence of mass surface when extrapolating to unknown superheavy nuclei is prone to significant theoretical uncertainties.Comment: 14 pages REVTeX, 8 eps figures, submitted to Phys. Rev.

Azimuthal anisotropy and correlations in p+p, d+Au and Au+Au collisions at 200 GeV

We present the first measurement of directed flow ($v_1$) at RHIC. $v_1$ is found to be consistent with zero at pseudorapidities $\eta$ from -1.2 to 1.2, then rises to the level of a couple of percent over the range $2.4 < |\eta| < 4$. The latter observation is similar to data from NA49 if the SPS rapidities are shifted by the difference in beam rapidity between RHIC and SPS. Back-to-back jets emitted out-of-plane are found to be suppressed more if compared to those emitted in-plane, which is consistent with {\it jet quenching}. Using the scalar product method, we systematically compared azimuthal correlations from p+p, d+Au and Au+Au collisions. Flow and non-flow from these three different collision systems are discussed.Comment: Quark Matter 2004 proceeding, 4 pages, 3 figure

Azimuthal anisotropy: the higher harmonics

We report the first observations of the fourth harmonic (v_4) in the azimuthal distribution of particles at RHIC. The measurement was done taking advantage of the large elliptic flow generated at RHIC. The integrated v_4 is about a factor of 10 smaller than v_2. For the sixth (v_6) and eighth (v_8) harmonics upper limits on the magnitudes are reported.Comment: 4 pages, 6 figures, contribution to the Quark Matter 2004 proceeding