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采用圆点印迹法检测GFkV,结果表明:Tris-HCl和PBS在提取GFkV时效果相同,在带毒葡萄植株中韧皮部的GFkV含量较高。 相似文献
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D.J. Robinson M.F.B. Dale D. Todd 《European journal of plant pathology / European Foundation for Plant Pathology》2004,110(9):921-928
Infection of potato plants with Tobacco rattle virus by its nematode vector can have different outcomes, including the development of spraing symptoms in progeny tubers. A novel syndrome described here comprises a generalized mottle in leaves on all stems, together with virtually total failure to produce daughter tubers. The outcome of infection depends partly on the potato genotype, but field trials with 15 varieties showed that the incidence and severity of spraing symptoms at three sites differed. There was no evidence that this was due to differences in virulence among the virus isolates at the sites, but it was probably the result of environmental differences that influenced the numbers and activity of the vector nematodes. At the most severely affected site, spraing symptoms were found in all varieties tested, except Record, including several that were not affected at the other two sites. Taking both severity and incidence of symptoms into account, the ranking of varieties was similar at each site. The incidence of spraing symptoms was greater in larger than in smaller tubers, and increased with later harvest dates, but did not increase when early harvested tubers were stored. Tobacco rattle viruswas detected in the roots of many of the weeds growing at one of the sites and in the roots of a few plants of the subsequent barley crop. 相似文献
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Judith Hübschen Lilo Kling Ulrike Ipach Volker Zinkernagel Nathalie Bosselut Daniel Esmenjaud Derek J.F. Brown Roy Neilson 《European journal of plant pathology / European Foundation for Plant Pathology》2004,110(8):779-788
Xiphinema diversicaudatum and X. index are vector nematode species of economic importance in viticulture regions as they can transmit Arabis Mosaic, Grapevine Fanleaf and Strawberry Latent Ringspot viruses to grapevine. Wang et al. (2003) designed species-specific diagnostic primers from ribosomal genes for both these vector species as well as a vector and a non-vector species X. italiae and X. vuittenezi, respectively. Our study aimed to confirm the specificity and determine the sensitivity and reliability of the primers for the two vector species, X. diversicaudatumand X. indexwhen challenged with closely related longidorid species and general nematode communities typical of vineyard soil. With one exception, no PCR product was observed when the primers were tested against six Longidorus, one Paralongidorus and one Xiphinema non-target species. Occasionally (three out of eight replicate PCR reactions) a weak PCR product was noted when primers for X. index were tested with L. elongatus. Furthermore, when challenged with a range of non-target nematode species comprising the nematode community typical of viticulture soil, no PCR product was amplified. An experimental dilution series of extracted DNA rigorously demonstrated that DNA from an equivalent single specimen of the target virus-vector species, X. diversicaudatum and/or X. index, could be detected amongst 1000 equivalent non-targetX. vuittenezi. Also, extracted DNA from an equivalent single target specimen was detected when added to DNA extracted from the overall soil nematode community. The primers were assessed further by using serial mixtures of actual nematodes rather than extracted DNA to simulate field soil. Using this method, a single target nematode could be detected amongst 200 non-target specimens. Given their specificity, sensitivity and reliability, it appears that these diagnostic primers will be of great benefit to phytosanitary/quarantine services related to the viticulture industry. 相似文献
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从延边黄牛卵巢中采集未成熟的卵母细胞进行体外成熟培养、体外受精及受精卵体外培养。结果表明 :1将卵子用 2种不同的培养液进行体外成熟培养和受精卵体外培养 ,TCM199组的卵裂率 (5 6 .3% )极显著高于 D- PBS组(33.6 % ) (P<0 .0 1) ;TCM199组的囊胚发育率和孵化率 (15 .1%、13.7% )虽高于 D- PBS组 (10 .5 %、8.7% ) ,但 2个组之间无显著差异 (P>0 .0 5 )。2以 TCM199作为基础培养液 ,分别用含激素培养液和不含激素培养液进行成熟培养和受精卵体外培养 ,添加激素组的卵裂率、囊胚发育率及囊胚孵化率 (81.2 %、17.5 %、15 .3% )高于没有添加激素的对照组 (75 .8%、12 .1%、10 .5 % ) ,但 2个组之间无显著差异 (P>0 .0 5 )。 3体外受精卵与单层颗粒细胞共培养组的卵裂率、囊胚发育率及囊胚孵化率 (78.0 %、11.5 %、9.9% )显著高于非共培养组 (6 8.1%、5 .4 %、3.6 % ) (P<0 .0 5 )。 相似文献
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鸭瘟病毒强毒株在急性人工感染成年鸭病例体内分布规律 总被引:7,自引:3,他引:7
5 6只 3月龄四川麻鸭经皮下接种鸭瘟病毒 (DPV)强毒 SC1株 ,成功建立了 DPV感染的急性病理模型 ,并应用PCR方法检测了不同时间 DPV在感染鸭体各组织器官的分布情况。结果表明 ,接种 2 h后 ,即能够从脑、肝、脾、法氏囊、胸腺中检出 DPV DNA;12 h,可从心脏、肝脏、脾脏、肺脏、肾脏、十二指肠、直肠、法氏囊、胸腺、胰腺、脑、胸肌、食管、腺胃、血液、舌、口腔分泌物、皮肤、骨髓和粪便等检测到 DPV的 DNA。检出时间最早和检出率最高的组织器官为肝脏和脑组织。本试验为阐明 DPV的致病机理和应用 PCR方法检测感染鸭体组织中的 DPV提供了重要的实验数据。 相似文献