首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2篇
  免费   0篇
植物保护   2篇
  2000年   2篇
排序方式: 共有2条查询结果,搜索用时 78 毫秒
1
1.
A variant of Cucumber mosaic virus, CMV(Y/GM2), was isolated from a tobacco plant with mild green mosaic symptoms that was regenerated in vitro from a yellow strain of CMV [CMV(Y)]-infected tobacco leaves by tissue culture. CMV(Y/GM2) has two amino acid substitutions at 36 and 111 positions in the coat protein encoded on RNA3. CMV, assembled by mixing in vitro transcribed CMV(Y) RNA1 and RNA2 plus infectious RNA3 transcribed in vitro from cDNA to RNA3 of CMV(Y/GM2), was prepared and designated as CMV(Y/GM2)tr. When tobacco (Nicotiana tabacum cv. Xanthi nc) plants were inoculated with CMV(Y/GM2)tr, large necrotic local lesions in which the virus was localized, developed on the inoculated leaves. This host response unique to CMV(Y/GM2)tr was similar to the hypersensitive response (HR), which is a common resistance response to avirulent pathogens and was observed in five cultivars of Nicotiana tabacum and eight Nicotiana species. The revertant virus, however, accumulated to quite different levels in the various hosts. CMV(Y/GM2)tr induced pathogenesis-related 1 (PR-1) protein accumulation and systemic acquired resistance (SAR) which were generally observed in the HR. However, when tobaccos were inoculated with CMV(S36P)tr and CMV(V111I)tr, which have an amino acid substitution at either the 36 or 111 position in the coat protein of CMV(Y), respectively, CMV(S36P)tr was restricted to the primary infection site without necrotic local lesion formation and PR-1 protein and SAR induction. CMV(V111I)tr, however, systemically spread and induced mild green mosaic symptoms, while the host had the HR to CMV(Y/GM2)tr. The localization of CMV(Y/GM2)tr at the primary infection site may not only be caused by the HR, but also by the restriction of virus systemic movement resulting from the amino acid substitution at position 36 in the coat protein of CMV(Y). Received 15 December 1999/ Accepted in revised form 18 April 2000  相似文献   
2.
We previously demonstrated that cowpea [Vigna unguiculata (L.) Walp.] cultivar Kurodane-Sanjaku contains the Cry gene, which confers resistance against Cucumber mosaic cucumovirus infection. In this paper, randomly amplified polymorphic DNA (RAPD) analysis was carried out to tag the Cry locus. Bulked segregant analysis for RAPD resulted in many polymorphisms in amplified DNA patterns. Candidates were further screened using parental and/or F2 cowpea DNAs. As a result, we obtained three RAPD markers, D13/E14-350, WA3-850 and OPE3-500, flanking the Cry locus. In addition, we amplified cowpea sequences coding for the putative nucleotide-binding site (NBS). Degenerate primers based on NBS sequences of tobacco N and Arabidopsis RPS2 disease resistance genes were used for polymerase chain reaction, and resultant products were cloned and sequenced. Among eight independent clones, cowpea resistance gene analog (CRGA) 5 showed a distinct polymorphism when used as a probe for restriction fragment length polymorphism analysis against the susceptible cowpea cultivar PI 189375 and a near-isogenic line for the Cry. Linkage analyses of these molecular markers showed that genetic distances of CRGA5, D13/E14-350, WA3-850 and OPE3-500 to the Cry locus were 0.7, 5.2, 11.5 and 24.5 cM, respectively. Received 16 December 1999/ Accepted in revised form 22 March 2000  相似文献   
1
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号