A survey of bacterial wilt in China collected 286 strains of Ralstonia solanacearum from 17 plant species in 13 Chinese provinces to investigate genetic diversity using the biovar (bv.) and phylotype classification schemes. A phylotype-specific multiplex-PCR showed that 198 isolates belonged to phylotype I (bv. 3, 4 and 5) and 68 to phylotype II (bv. 2 and bv. 1). A phylogenetic analysis examined the partial sequence of the egl and hrpB gene of all strains and the genetic diversity of 95 representatives was reported, demonstrating that Chinese strains are partitioned into phylotype I (Asia) and II (Americas). Phylotype I strains (historically typed bv. 3, 4 and 5), had considerable phylogenetic diversity, including 10 different sequevars: seven previously described sequevars 12 to 18 and three new sequevars: 34, 44 and 48. Chinese strains Z1, Z2, Z3, Z7, Pe74 and Tm82 were not genetically distinguishable from the edible ginger reference strain ACH92 (r4-bv. 4) for sequevar 16. This is believed to be the first report of this ginger group in China. All Chinese bv. 2 strains falling into the genetically and phenotypically diverse phylotype II were placed into phylotype IIB sequevar 1 (historically the Andean race3-bv. 2 potato brown rot agent). In both the egl and hrpB sequence-based trees, strains isolated from mulberry were present in two distinct branches found in sequevars 12 and 48 (reference strains R292 and M2, respectively).

Our statistics on Galactic supernova remnants (SNRs) shows that the electrons temperature (T ) of hard X-ray and the shock waves traveling velocity (υ) decreases with ages (t) for allsort remnants. However, the shock waves swept-up mass (M su ) of ISM increases with the age. Second, the remnant radio fluxes (S) at 1 GHz increase slightly with ISM electrons density (n 0 ). At last, the number distributions illustrate that the supernovae (SNe) initial kinetic energy (E 0 ), hydrogen column density (N H ), electrons temperature (kT) of hard X-ray, magnetic field (B) and the shock waves swept-up mass (M su ) of ISM mainly peaked at (1 ∼ 10) × 10 50 ergs, (1 ∼ 10) × 10 21 cm −2 , a few KeV, 100 µG and 10∼100 M ⊙ , respectively.

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