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RFLP tagging of a salt tolerance gene in rice 总被引:10,自引:0,他引:10
A salt tolerant rice mutant (M-20) was obtained through selection in vitro. Its tolerance was stably inherited over eight generations and most traints between M-20 and its sensitive original 77–170 (Oryza sativa) were very similar. By deriving an F2 population of M-20 × 77–170 and splitting every F2 individual into two parts, with one part planted in normal conditions and another part in saline conditions, the inheritance of salt tolerance in rice was studied. Under normal conditions, there was no apparent segregation among F2 individuals. Under saline conditions, however, the segregation of traits was obvious. According to our standards, the ratio of salt sensitive:moderately-tolerant:tolerant plants was 25:42:18, in accordance with a 1:2:1 ratio. It suggested that the improvement of salt tolerance in our materials was induced by the mutation of a major tolerant gene which showed incomplete dominance. By use of 130 RFLP probes distributed throughout the rice genome, the gene was tagged by a single copy DNA probe, RG4, which was located on chromosome 7. The genetic distance between the salt tolerant gene and RG4 was 7.0 ± 2.9 cM. Based on the split method, a method which could be currently used to evaluate the damage of salt stress in rice was proposed. 相似文献
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罗汉果双受精过程的细胞学观察 总被引:3,自引:1,他引:2
罗汉果(Siraitiagrosvenori(Swingle)C.Jemey)双受精过程属有丝分裂前配子融合类型,授粉后24~48h,花粉管进入胚囊,穿过一个助细胞,放出两个精子。雌雄核融合和雄核与次生核融合同时发生在授粉后62~72,雄核与次生核融合速度快于配子融合,72h后即可见到初生胚乳核分裂。合子中的雌雄核仁在授粉后第5~6d融合,授粉后8~9d合成分裂形成二细胞胚。在双受精过程中,多次观察到有多条花粉管进入胚囊和多精入极核现象。原胚期有附加花粉管从珠孔进入。 相似文献
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足月分娩的新鲜胎盘组织制成匀浆后,经高速离心、超速离心,谷胱甘肽(GSH)Sepharose 6B亲合层析,Amicon pM-10膜超过滤及高效液相层析,最终经SDS-PAGE鉴定,结果呈现单一亚基区带,其亚基分子量为25000。 根据我们现有高效液相设备条件,用ODS柱代替RadulovicL等报道的特异阴离子柱,用磷酸盐洗脱液代替含谷胱甘肽、二硫苏糖醇及氯化钾的梯度洗脱液,从人胎盘组织成功地制备了谷胱甘肽硫转移酶(GST)纯酶,全过程在15min内完成,保留时间及主峰面积的重复性均较理想,7次实验结果的变异系数为0.2%,最终纯化578.9倍。本研究为各种形式GST的纯化制备提供了一个新的、重复性好、分辨率高及回收理想的简易方法。 相似文献
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Triterpenoid saponins from Clinopodium polycephalum. 总被引:4,自引:0,他引:4
A new triterpenoid saponin, clinopodiside A, has been isolated from Clinopodium polycephalum. Its structure was established by spectroscopic methods and X-ray diffraction analysis as 3-O-beta-D-glucopyranosyl(1----6)-[ beta-D-glucopyranosyl (1----4)]-beta-D-glucopyranosyl-olean-11,13(18)-diene-3 beta,16 beta, 23,28-tetrol. 相似文献
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Ting Xue Wei-Qin Du Wen-Juan Dai Yi-Shan Li Shu-Feng Wang Jun-Ling Wang Xin-Ri Zhang 《Polish journal of microbiology》2022,71(1):27
Pneumocystis jirovecii is an opportunistic fungus that can cause severe and potentially fatal Pneumocystis pneumonia (PCP) in immunodeficient patients. In this study, we investigated the genetic polymorphisms of P. jirovecii at eight different loci, including six nuclear genes (ITS, 26S rRNA, sod, dhps, dhfr and β-Tub) and two mitochondrial genes (mtLSU-rRNA and cyb) in three PCP cases, including two patients with HIV infection and one without HIV infection in Shanxi Province, P.R. China. The gene targets were amplified by PCR followed by sequencing of plasmid clones. The HIV-negative patient showed a coinfection with two genotypes of P. jirovecii at six of the eight loci sequenced. Of the two HIV-positive patients, one showed a coinfection with two genotypes of P. jirovecii at the same two of the six loci as in the HIV-negative patient, while the other showed a single infection at all eight loci sequenced. None of the three drug target genes (dhfr, dhps and cyb) showed mutations known to be potentially associated with drug resistance. This is the first report of genetic polymorphisms of P. jirovecii in PCP patients in Shanxi Province, China. Our findings expand our understanding of the genetic diversity of P. jirovecii in China. Open in a separate window 相似文献
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A subsystem impactor test for pedestrian lower limb injury evaluation has been brought in China New Car Assessment Protocol(CNCAP).Concerning large anthropometr... 相似文献