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51.
马铃薯植株感染Y病毒后生理指标变化与抗病性的关系   总被引:1,自引:0,他引:1  
夏平 《中国马铃薯》2007,21(3):129-133
本研究分别以对PVY感病、过敏和极端抗性的品种脱毒试管苗为材料,比较了接种PVY后不同时间内超氧化物歧化酶(SOD)和游离脯氨酸含量2个指标的变化。从整体上看,未接种PVY条件下,感病品种(Superior)植株的SOD活性较极端抗性品种(IVP35)和过敏型品种(Desiree)低。接种后,IVP35的SOD活性下降;Desiree在接种前期0.5~1 d SOD的活性下降,2~7 d后SOD活性上升,再后7~14 d又下降;Superior接种PVY后,SOD活性有上升趋势,且在接种2~3 d变化率出现最大值。另外,IVP35和Desiree在接种PVY后SOD变化率小,变化范围分别为-13.4%~4.6%和-17.8%~8.7%;Superior接种PVY后,SOD活性变幅较大,范围为5.1%~79.2%。被测的3个品种无论接种与否,极端抗性品种和过敏型品种其植株内部游离脯氨酸含量均明显高于感病品种。正常情况下,IVP35和Desiree的游离脯氨酸含量为41.39~48.77μg.g-1干重和33.42~39.11μg.g-1干重,而Superior仅为8.91~10.72μg.g-1干重。接种PVY后,Superior的游离脯氨酸含量明显上升,达到11.23~21.54μg.g-1干重;虽然IVP35和Desiree的游离脯氨酸含量也呈上升趋势,但上升幅度小,含量分别为48.92~72.13μg.g-1干重和42.46~71.34μg.g-1干重。  相似文献   
52.
烟草感染马铃薯Y病毒(PVY)后光合作用的变化规律   总被引:14,自引:1,他引:14       下载免费PDF全文
以马铃薯Y病毒(PVY)为毒源,以烟草NC89为材料,采取光合指标和超微结构相结合的研究方法,对感染PVY烟草的叶绿素含量、光合速率等生理指标以及叶绿体结构变化的规律进行了研究。结果表明:在光照、温度、湿度、CO2浓度和土壤水分都相对恒定的条件下,烟草NC89感染马铃薯Y病毒(PVY)后,烟草的叶绿素含量、光合速率、气孔导度、蒸腾速率都出现了不同程度的降低,而细胞间CO2浓度有所升高,Hill反应的活性却明显下降,叶绿体超微结构受到明显的破坏。  相似文献   
53.
马铃薯Y病毒研究进展   总被引:3,自引:1,他引:3  
马铃薯Y病毒(Potato virus Y,PVY)是危害马铃薯的重要病毒之一,在全球广为传播,并造成了严重经济损失。因此深入研究PVY及其与马铃薯的相互作用有助于控制病毒,减轻危害。根据初始寄主植物,PVY可分为以马铃薯为初始寄主的株系群体和以非马铃薯物种为初始寄主的株系群体。以马铃薯为初始寄主的株系群体,依据指示寄主植物(马铃薯品种,烟草)反应,进一步分为PVYO、PVYN、PVYNTN及PVYC等几种类型。依据血清学反应,PVY分成PVYO/C血清型和PVYN血清型。依据基因序列和基因组学,PVY分为PVYO,PVYN,PVYC及一系列PVYO/PVYN重组型如PVYNTN和PVYN:O。症状是寄主与病毒之间复杂的相互作用的结果。一些病毒蛋白和寄主蛋白的相互作用已被证实或逐渐认识到。证据显示HC-Pro起到转录后基因沉默抑制子的作用,从而提高病毒复制能力。马铃薯对PVY的抗性分为极端抗性和高敏抗性两类,多个极端抗性基因(即Ry基因)和过敏抗性基因(即Ny基因)被定位在第9,11和12号染色体上。PVY与植物的分子互作和抗PVY基因资源挖掘与利用将是今后几年的研究重点。  相似文献   
54.
The aphid-vectored Potato virus Y (PVY) is currently seen as an important limiting factor in the production of potatoes in many countries. Using a content-analysis approach, we investigated the German extension literature for recommendations regarding the control of PVY. Media included articles from periodicals addressing farmers and agricultural textbooks published in the last five decades (1955–2004). In the current literature (1995–2004), the clearly dominating strategy was found to be insecticidal control, although this strategy has been subject to some criticism in the scientific literature. Over the last five decades we also found a strongly increasing representation of insecticidal strategies. Furthermore, over this period of time, information diversity, measured as the number of different strategies proposed per article or per textbook, decreased consistently. Electronic supplementary material The online version of this article () contains supplementary material that is available to authorized users.  相似文献   
55.
PVYCP基因导入加工型马铃薯甘农薯1号的研究   总被引:1,自引:0,他引:1  
利用整合有马铃薯Y病毒外壳蛋白基 (PVYCP基因 )的改建质粒PEY3,以土壤农杆菌为载体转化加工型马铃薯新品种甘农薯 1号叶盘 ,细菌侵染 14d后用 10 0ml/LKM在愈伤组织水平上选择 ,转化率最高可达 2 1 3%。转化效率与细菌生理状态、NAA浓度、叶盘预培养天数有关。转化体分化 2株再生植株。冠瘿碱分析证明转化体整合了PVYCP基因。  相似文献   
56.
用生物学方法研究了河南烟草马铃薯Y病毒(PVY)的体外特性.结果表明,河南PVY的稀释限点为10^-6~10^-7.致死温度为70~75℃,体外存活期为4~6d,在PVY与CMV,TMV相互作用的研究中发现混合侵染的症状比单独侵染严重.且表现症状不同.  相似文献   
57.
Shoot apices from six diploid potato genotypes for polyploidisation were treated with oryzalin and colchicine solutions at different concentrations and incubation times. In addition to chimeric plants, diploids, one octoploid and completely ploidy doubled plants (4x) were regenerated in these experiments. Tetraploid plants were obtained for three of the six genotypes treated with oryzalin, and no tetraploid plants were obtained after colchicine treatments of any of the genotypes. The best result of 43% tetraploid plants was achieved using 28.8 μM oryzalin and 24 h of incubation with the L37 genotype. Moreover, we determined that doubled plants should not be selected on the basis of a single measurement and require additional ploidy checks in successive clonal generations. Some L37 plants that were initially identified as tetraploids by flow cytometry produced diploid or mixoploid plants in the next clonal generation. Morphological characters of doubled L37 plants were compared with the original genotype. The PVY resistance present in a parental clone was maintained in all regenerants and significant differences among ploidy variants were found for some quantitative characters. Molecular AFLP analyses did not show any differences among genotypes. Since polyploidizing substances may produce a large proportion of chimeric plants, we applied a method to increase the number of tetraploid plants. Callus culture of chimeric leaf explants was performed on regeneration medium and tetraploid shoots were obtained in four of the six genotypes tested. The best result of 40% tetraploid plants was achieved with explants from the L37 genotype. This method was successful in producing additional tetraploid genotypes from mixoploid plants obtained after oryzalin treatments.  相似文献   
58.
S. Marco 《Potato Research》1984,27(4):431-434
Summary The Mount Katerina area is isolated, in the middle of the Sinai Desert, and its peak is at an altitude of 2647 m. Trapping with yellow water traps showed that winged aphid populations are small and active mainly in the spring and only until May. Virus-tested tubers of cv. Up-do-Date were planted on 18 May and harvested on 27–29 September. No PLRV, PVY or PVX infection was detected in 319 haulm samples and in 96 progeny tubers. When the Mt Katerina tubers were planted the next spring, they yielded 11% and 7% more than imported and Golan seeds respectively (non-significant differences) and emerged to a greater extent. The results indicate that the Mt Katerina area may be suitable for growing high quality seed-potatoes. Supported in part by BARD Project US-3399-80. Contribution No 815-E, 1983 Series.  相似文献   
59.
受体细胞倍性对PVY CP基因向马铃薯遗传转化影响的研究   总被引:2,自引:0,他引:2  
师桂英 《中国马铃薯》2001,15(4):204-206
利用整合PVYCP基因的改建质粒PEY3,以农杆菌为载体向四倍体栽培“甘农薯 1号” (2n =4x =4 8)及双单倍体“84 4 7” (2n =2x =2 4 )叶盘、叶柄、茎段导入PVYCP基因并获得再生植株。愈伤组织卡那霉素 (KM )抗性筛选试验表明 ,低倍体受体细胞利于外源基因的整合与表达 ,双单倍体转化率 (2 5 4 % )高于四倍体 (15 8% )。冠瘿碱分析证明再生植株整合了PVYCP基因。染色体倍性鉴定证明转基因再生植株与亲本倍性一致。  相似文献   
60.
S. Marco 《Potato Research》1981,24(2):135-145
Summary Seed potatoes grown during winter in the Sinai Desert (Sharm el Sheik) yielded in autumn significantly more (17%) than commercial seed grown in spring. Seeds grown in winter in an agricultural area at Yotvata yielded similarly to the commercial controls. Almost no spread of PVY or PLRV was found at Sharm probably because of the very low alate population there, whereas at Yotvata the incidence of PLRV was over 40% probably as a consequence of a high aphid populations during the growing season. Alate populations were also observed in the Sinai Desert at A-tur, a completely arid area, and at Firan, an isolated oasis where agriculture is practised. At A-tur only a few alatae were trapped, but large numbers were found at Firan, especially starting in March, but not during winter the proposed season for growing seed potatoes. The possibility of growing high quality seed potatoes at Sharm is discussed. Contribution No 107, 1980 series, Volcani Center.  相似文献   
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