One hundred and ninety three parental lines obtained from 26 countries for an international rice molecular breeding program were evaluated using 101 well-distributed simple sequence repeat (SSR) markers. An overall genetic diversity of 0.68 and an average of 6.3 alleles per locus were revealed, indicating a high level of genetic variation in these lines. Cluster analysis of the 193 accessions showed three major groups and nine subgroups. Group I corresponded to the classical indica subspecies, whereas groups II and III belong to the japonica subspecies. Indica and japonica differentiation accounted for only 6.5% of the total variation in the entire sample and 93.5% was due to within-subspecies diversity. Differentiation among eco-geographic regions accounted for 24% of the diversity within the subspecies. Larger amounts of the eco-geographical differentiation were resolved within japonica than within indica. The largest indica-japonica differentiation based on the single locus level was detected by markers on chromosomes 9 and 12, while the smallest differentiation was detected by markers on chromosomes 4 and 8. Furthermore, genetic differences at the single-locus and two-locus levels, as well as components due to allelic and gametic differentiation, were revealed between indica and japonica and among the main geographic regions. The multilocus analysis in genetic diversity showed a higher proportion of variation caused by predominant non-random associations of different loci within and among the classified subspecies and geographic subdivisions. The results suggest that selection for eco-geographical adaptation on multilocus associations was largely responsible for the maintenance of the extensive variation in the primary gene pool of rice.

China is particularly rich in goose genetic resources. Systematic study of the genetic diversity and origin of Chinese domestic geese will provide an important scientific basis for the conservation and utilization of these resources and for human history. The 521-bp control region (D-loop) of mitochondrial DNA from 26 goose breeds and 6 Landaise geese were sequenced. The results showed that the average haplotype diversity and nucleotide diversity of Chinese domestic geese were 0.1384 and 0.00029, respectively. Shared haplotype analysis and systematic evolution analysis revealed that Chinese domestic geese had 2 maternal origins. The Yili goose breed originated from the Greylag goose (Anser anser), and the other 25 domestic goose breeds originated from the swan goose (Anser cygnoides). An interesting finding was that 1 Linxian white goose and 1 Wanxi white goose shared the same H4 haplotype with the Rhine goose and the Landaise goose, which originated from the Greylag goose (A. anser). Further research on this finding is planned.

Fusarium head blight (FHB) is a worldwide devastating disease of wheat, caused primarily by species in the Fusarium graminearum (Fg) complex. In this study, we obtained 55 Fusarium isolates from wheat with FHB collected from seven provinces along the north of the Yangtze River. One additional phylogenetic species of Fg complex, Fusarium meridionale, was identified for the first time from China in addition to two known ones, Fusarium asiaticum and F. graminearum. In addition, Fusarium acuminatum, distantly related to Fg complex, was for the first time identified in Northern China. Sensitivities of these isolates to carbendazim were examined and appeared to vary both within and between species. Mycotoxin genotype analyses indicated that F. asiaticum isolates were potential 3-Ac-DON and NIV mycotoxin producers, while all F. graminearum isolates might be 15-AcDON producers. These findings would provide useful information for developing management strategies for the control of FHB in Northern China.

A short and efficient route of synthesis and structural characterization of a series of novel N‐dichloroacetyl‐1,3‐oxazolidine derivatives has been developed. These new compounds characterized of the disubstitution at position 2 by alkyl, cycloalkane, and phenyl were synthesized in good yields via a sequential procedure involving condensation and acylation. All the compounds are characterized by IR, 1H NMR, 13C NMR, and element analysis. J. Heterocyclic Chem., (2010).

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A series of novel N-dichloroacetyl-l,3-oxazolidine derivatives 4 were synthesized by a convenient one-pot synthesis involving cycloaddition reaction of -amino alcohol 1 with aldehyde or ketone 2 in benzene and acylation of oxazolidines 3 with dichloroacetyl chloride. The structures of the compounds were characterized by IR, Ή NMR, 13 C NMR and element analysis. The preliminary biological test showed that the compounds could protect maize against injury caused by chlorsulfuron in some extent.

Neuroendocrine carcinoma of the breast is a rare malignant tumor which, with the features of Merkel cells is even rarer. Herein, we report a case of small cell carcinoma with Merkel cell features in a 52-year-old female. Microscopically, the tumor was characterized by diffuse and consistent small round cells that were de-adherent. The tumor cells had round or oval nuclei with delicate chromatin and small nucleoli, the cytoplasm was sparse and eosinophilic. Additionally, the tumor was accompanied by high-grade ductal carcinoma in situ. Immunohistochemical staining showed that infiltrating tumor cells were positive for neuroendocrine markers, and punctately positive for CK20. The patient underwent modified radical mastectomy, axillary lymph node dissection, and postoperative adjuvant chemotherapy. No recurrence or metastasis was observed during follow-up period. Primary breast small cell carcinoma with Merkel cell features is rare and easily misdiagnosed as Merkel cell carcinoma. Early diagnosis and treatment may improve patient prognosis.