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51.
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The present paper reports the chromosome numbers and karyotypes of 5 species
in Ranunculus from Jiangxi. The result is shown in Table 1-2. The chromosome numbers of
R. ternatus Thunb. (2n=4x=32; 2n=2x=16=8m+2sm+6st) , R. polii Franch.
(2n = 2x = 16 = 8m+2sm+6st) and R. sieboldii Miq. (2n = 8x-1 = 63 = 15m+18sm+22st+8t) are
first reported. The essential points are as follows:
(1) The karyotypes of R. ternatus Thunb. and R. polii Franch. are rather similar, which
shows a close relationship between the two species.
(2) Polyploid complexes are common in Ranunculus.
(3) According to the taxonomical system of Wang Wen-cai, the karyotypes of the two
species investigated in Sect. Auricomus belong to “2A” of Stebbins; that of the only species in
Sect. Hecatonia belong to “2B'; the karyotypes of the two species investigated in Sect.
Ranunculus belong to “3A” or “3B”. The relationships among the three sections from thekaryotype are basically consistent with those based on morphology. 相似文献
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Lin Xu Yong Zhang Zheng Shan Deng Liang Zhao Xiu Li Wei Ge Hong Wei 《Antonie van Leeuwenhoek》2013,103(3):559-565
During a study of the diversity and phylogeny of rhizobia isolated from root nodules of Oxytropis ochrocephala grown in the northwest of China, four strains were classified in the genus Rhizobium on the basis of their 16S rRNA gene sequences. These strains have identical 16S rRNA gene sequences, which showed a mean similarity of 94.4 % with the most closely related species, Rhizobium oryzae. Analysis of recA and glnA sequences showed that these strains have less than 88.1 and 88.7 % similarity with the defined species of Rhizobium, respectively. The genetic diversity revealed by ERIC-PCR fingerprinting indicated that the isolates correspond to different strains. Strain CCNWQLS01T contains Q-10 as the predominant ubiquinone. The major fatty acids were identified as feature 8 (C18: 1ω7c and/or C18: 1ω6c; 67.2 %). Therefore, a novel species Rhizobium qilianshanense sp. nov. is proposed, and CCNWQLS01T (= ACCC 05747T = JCM 18337T) is designated as the type strain. 相似文献
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SIRT1 expression is refractory to hypoxia and inflammatory cytokines in nucleus pulposus cells: Novel regulation by HIF‐1α and NF‐κB signaling 下载免费PDF全文
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