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71.
Yong Liu Dongcheng Liu Haiying Zhang Jing Wang Jiazhu Sun Xiaoli Guo Aimin Zhang 《Euphytica》2005,145(1-2):103-112
Wheat microsatellite XGWM261, due to its closely linked to the dwarfing gene Rht8, has been adopted as the diagnostic molecular marker of Rht8. Screening 408 Chinese and 98 exotic varieties showed 13 allele variants in locus of XGWM261, with 6 alleles only to be found
in Chinese varieties and 2 only in exotic varieties, respectively. Sequencing results of the 13 alleles revealed their absolute
fragment sizes with 216, 212, 210, 206, 204, 202, 200, 196, 194, 192, 190, 174, and 164 bp, respectively. Allelic distribution
analysis showed that the 204, 192, 174, and 164 bp alleles were prevailing in Chinese varieties, and the diagnostic 192 bp
allele to Rht8 had a very high percentage in the Yellow and Huai River Valleys Facultative Wheat Zone than in the Northern Winter Wheat
Zone in China. The GT → AC substitution at position 35 was found in 216, 200, and 174 bp alleles. Moreover, the AG insertion
immediately at the end of CT-repeat region was also found in 216, 200, 174, and 164 bp alleles. 相似文献
72.
Summary Freshly cut leaves of Kohleria eriantha and K. x Longwood were exposed to a wide range of gamma irradiation doses and allowed to root and form adventitious buds. K. Eriantha could not be successfully propagated from leaf half cuttings. Longwood produced a small number of adventitious plantlets as compared to other Gesneriads. Colchicine treatments reduced leaf half survival in Longwood by more than 50%. Leaf halves exposed to low and moderate doses of gamma irradiation showed increased overall plantlet production compared to nonirradiated leaf halves.Of the mutation parameters calculated, the number of mutants per 100 surviving leaf halves appears to be the most useful since it relates the number of mutants within a dose to the number of surviving leaf halves, the number of mutants to the number of plants produced, and the number of mutants within doses to control values.Using the criteria, number of mutants per 100 surviving leaf halves, optimum production of all mutants, of useful and of dwarf mutants was obtained at 2.5 kR for noncolchicine treated leaf halves and 1.5 to 3.0 kR for colchicine treated leaf halves.Of the adventitious plantlets produced, 13.8% were classified as mutant types. Mutant plants were found in radiation dose levels up to 5.5 kR. The array of mutants produced was skewed toward plant habit and flower characteristic mutants with several leaf characteristic, lethal, and polyploid mutants observed. A high frequency of mutants, 10 of 93 plants, occurred in the nonirradiated controls. Four sectorial chimeras were identified from both control and irradiation exposed groups. Several potentially useful flower color and dwarf mutants have been selected for further study. Adventitious buds may have developed from callus at petiole and leaf-vein bases. Colchicine treatments severely inhibited adventitious plantlet production and because of this could not be used as a criterion to identify the origin of adventitious buds. Conclusive determination of the organogenesis of adventitious buds from Longwood leaf halves could not be made. Mutant plantlets formed from adventitious buds on detached leaf halves of Longwood appear to arise from single cells as has been found with other Gesneriads.Scientific Journal Series Article No. 10 330 of the Minnesota Agricultural Experiment Station. 相似文献
73.
A wheat microsatellite locus, Xgwm 261, whose 192-bp allele closelylinked to the dwarfing gene Rht8, on chromosome 2D, was used toscreen 71 wheat cultivars from 13 countries to assess the variation at thislocus. Screening of this wheat collection showed that a 165-bp allele anda 174-bp allele were the most frequent. None of the New Zealand cultivarspossessed a 192-bp allele specific to Rht8, while only one cultivarfrom the US produced this important allele. The frequency of a 192-bpallele among these wheat cultivars was 5.63%. The highest allelefrequency was observed for a 174-bp fragment (52.11%) followed by a165-bp fragment (26.76%). The only durum wheat `Cham 1', did notshow any amplification due to the absence of D genome. Four new novelalleles, 180-bp, 198-bp, 200-bp and 204-bp present in the US and NewZealand wheat cultivars are reported. 相似文献
74.
Rudolf Hofer Reinhard Lackner Joachim Kargl Bertha Thaler Danilo Tait Leopoldo Bonetti Raffaele Vistocco Giovanna Flaim 《Water, air, and soil pollution》2001,125(1):189-200
Southern populations of the European minnow fromremote oligotrophic mountain lakes along an Alpinenorth-south transect accumulated more p,p DDE andPCBs than northern populations. As these semi-volatileorganochlorines predominantly evaporate in warmcountries, higher rates of condensation (deposition)are assumed to occur in the southern slopes of theAlps. The higher accumulation of lead and cadmium insouthern population is rather attributed to geogenicand specific environmental impacts than to atmosphericdeposition. Increasing liver ratios of [glutathionedisulfide]/[glutathione], a potential indicator foroxidative stress, from north to south reflect thegenerally higher toxic load at remote sites at thesouthern edge of the Alps. However, histopathologicalchanges in the liver did not correlate withaccumulated toxicants indicating that deposition doesnot lead to severe lesions but induces specificmechanisms for detoxification. 相似文献
76.
新城疫病毒F_(48)E_8株cDNA文库的构建 总被引:1,自引:0,他引:1
以SPF鸡胚繁殖我国标准新城疫病毒F_(48)E_8强毒株,经蔗糖密度梯度超速离心纯化病毒。再以酚-SDS法提取病毒基因组RNA,作为反应模板、采用Promega公司商品试剂盒合成双股cDNA。以同聚物加尾的方法将cDNA克隆到质粒pGEM3Zf(一)中,经AIX平板筛选,限制性内切酶分析和Digoxigenin标记的核酸探针检测,共获得插入外源片段大小在0.6~4.8kb的阳性克隆75个,初步构建了F_(48)E_8株的cDNA文库 相似文献
77.
高产水稻新品种“漳丰8号”的选育 总被引:1,自引:0,他引:1
利用本所的育种中间材料漳丰矮与巨丰稻杂交,经多代选育育成了早籼迟熟新品种漳丰8号。该品种株叶型态理想、高产、抗稻瘟病和白叶枯病、纹枯病发生轻、后期转色好、抗倒性强。在2003~2004年漳州市区试中,两年平均比对照特优77增产5.21%。 相似文献
78.
目的:探讨慢性阻塞性肺疾病(COPD)的气道反应性IL-8因子在COPD发病中的作用,方法:用组胺气道吸入激发试验观察缓解期COPD,哮喘和健康人的气道反应性,同时测定气道激发前后血清IL-8水平变化。结果:COPD和哮喘患者均呈气道高反应性,且COPD组PD50FEV1与FEV1/Pre%(P〈0.02,P〈0.05),IL-8水平与PD20FEV1无显著相关性,气道激发后,COPD和哮喘血清I 相似文献
79.
80.