首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 250 毫秒
1.
 Hyphal cell wall crude elicitor(CWE)of rice blast pathogen could induce hypersensitive response in tobacco and induce other nonhost plants to be resistant to other fungal pathogens.When corn was treated with CWE,they inhibited the infection of Exserohilum turcicum and Curvularia lunata,and when plants of capsicum and cucumber were treated with CWE,they inhibited the infection of Colletotrichum gloeospori-oides.CWE solution showed no bioactivity on spore germination and hyphal growth of the experiment fungi in vitro.Nonhost resistance induced by CWE to other fungal pathogens was not complete resistance.The induced resistant effect(IRE) increased as CWE concentration increased,however,IRE had somehow satura-ted concentration of CWE.Induced nonhost resistance by incompatible pathogen was quantitative to other compatible pathogens.The induced resistance was best at 2 or 3 d after CWE treatment,and then decreased.IRE was about 20 percent in 10 d after CWE treatment.  相似文献   

2.
 Using resistant and susceptible cultivars as controls, the resistant evaluation to Pseudoperonospora cubensis was carried out in 12 introgression lines from wide cross between cucumber(Cucumis sativus L.) and sour cucumber(Cucumis hystrix Chakr.). Three enzyme activities including POD, SOD and PAL were analyzed before and 7 d after inoculation, and the POD isozyme was detected by polyacrylamide electrophoresis. The inoculation results showed that, of the 12 accessions, 3 were identified as high resistant, 5 were moderately resistant and 4 were moderately susceptible to downy mildew. The enzyme activities of POD, SOD and PAL were greatly increased in resistant accessions after inoculation. PAL enzyme activities showed close correlation with disease rating before or after inoculation, which implicated that PAL enzyme activity might be used to estimate the resistance to downy mildew. POD isozyme electrophoresis showed that the number and intensity for the bands of resistant lines were significantly increased more than those of susceptible lines after inoculation.  相似文献   

3.
 Root rot of American ginseng (Panax quinquefolium) caused by Ditylenchus destructor is a novel disease found recently in Beijing area. The effects of three soil treatments (fumigating with chloropicrin, chloropicrin + lvfeng organic manure and nematicide fosthiazate) on the number of rhizospheric nematodes, survived plants, root yield and root rot of 3-year ginseng plant were compared. The effects were also investigated at the second year after treatment. The results indicated that the number of parasitic nematodes in rhizosphere of treated soil reached the peak value in late June to early July as the soil temperature raised in the growing season. Compared with the regular treatment, the number of plant parasitic nematodes was reduced while non-plant parasitic nematodes increased. The number of non-plant parasitic nematodes in the soil treated with chloropicrin + lvfeng organic manure was 2 times than that treated with chloropicrin only. The ratio of non-parasitic to parasitic nematodes of three treatments was higher than the control. Percent of survived plants was 94.8%-96.4% and diseased root was decreased obviously. The control efficacy was more than 89% at the first year after treatment. The survived plants and plot yield of ginseng increased significantly and the control efficacy was around 40% at the second year. The best of the three treatments was by chloropicrin + organic manure.  相似文献   

4.
 ORFⅡ gene of Banana streak virus GuangDong isolate (BSV-GD) was amplified from a BSV-GD recombinant plasmid by PCR, and the gene was expressed by being cloned into prokaryote expression vector pET-28b (+). The fusion protein was about 16.5 kDa in size and was soluble with SDS-PAGE analysis. The purified protein was obtained by using the histidine labeling kit of N-terminus of protein. The antiserum was obtained by immunizing healthy rabbits with the purified protein. Western blot and ELISA analysis showed that the special antiserum of BSV possessed high titer, which was tested as 1:51 200. The study was a base for further research on BSV including ORFⅡ gene function and virus detection.  相似文献   

5.
分子标记辅助选择小麦抗白粉病兼抗赤霉病聚合体   总被引:1,自引:0,他引:1  
 Sumai 3, a wheat variety resistant to Fusarium head blight(FHB), was crossed with Neimai 9, a commercial wheat cultivar with the resistance to powdery mildew.The SCAR(sequence characterized amplified region) markers of powdery mildew resistance gene Pm21 and four SSR(simple sequence repeats)markers flanking the major FHB resistance QTL(Qfhs.ndsu-3BS) in Sumai 3 were used to detect the resistance loci by marker assisted selection(MAS) in the plants of the F2 population.Identification of resistance to both powdery mildew and FHB in field showed that 12 plants resistant to both diseases were obtained.In addition, the agronomic traits of these plants were better than those of Sumai 3, and are perhaps the excellent parental materials for wheat breeding.  相似文献   

6.
7.
 The changes of several defense enzyme activities and phenolic compound in cucumber roots were examined after biological soil amendment(BSA) was applied to the cucumber continuous cropping through pot trials.It could promote seedling growth and reduce disease incidence.The results showed that the activities of defense enzymes such as peroxidase(POD),polyphenol oxidase(PPO) and TTC in treated cucumber roots were measured significantly higher than that of control.The activities of POD and PPO in BSA-treated roots were significantly higher than that of control after inoculation with Fusarium oxysporum(Schl.)f.sp.Cucumerinum.Phenolic compound content of roots decreased in the initial period of inoculation,increased after di-sease incidence,but it was higher in BSA-treated than that of control.These indicated that BSA could induce the defense enzyme activities and increased phenolic compound in cucumber roots.  相似文献   

8.
江彤  陈伟 《植物病理学报》2009,39(5):540-543
 Tobacco and potato samples showing symptoms of PVY were collected from different regions in Anhui Province, and the ELISA results of partial samples were positive. The total RNA was extracted from the positive samples by TRIZOL methods. Specific primer pair was designed to amplify cp gene of PVY by RT-PCR. Sequencing results indicated that the full length of cp gene of PVY from tobacco (PVY-CP-4) and pota-to (PVY-CP-7) is 801 nts, and each of them encodes 266 amino acids. A phylogenetic tree based on alignment of cp nucleotide sequences was constructed and the sequence comparing of cp gene was conducted. The results showed that PVY-CP-4 could be grouped into one branch with PVYO and PVYN:O and shared the highest sequence similarity (99.4%) with PVYO (EF026074). It was suggested that PVY-CP-4 derived from tobacco in Hefei might belong to PVYO. PVY-CP-7 clustered together with PVYN and PVYNTN and formed another branch. Furthermore, PVY-CP-7 shared the highest sequence similarity (98.3%) with PVYNTN(AJ890347), PVYNTN (EF026075) and PVYNTN(AJ585342). It was supposed that PVY-CP-7 derived from potato in Wuhe probably belonged to PVYNTN.  相似文献   

9.
 Sugarcane bacilliform virus(SCBV) was detected by PCR from sugarcane showing chlorosis and mottle symptom from Kaiyuan, Yunnan Province.Part sequence of replicase gene of the isolate SCBV-Kaiyuan was determined.Sequence analysis indicated that the 589 bp of SCBV-Kaiyuan shared identities of 73.2%-74.0% and 83.1%-84.1% at nucleotide and amino acid levels with SCBV-Australia respectively, 66.7%-68.4% and 65.6%-67.7% with SCBV-Morocco.The quality and yield of the sugarcane infected with SCBV-Kaiyuan was also investigated.The juice extraction, sucrose content, gravity purity and average stalk weight were decreased 1.55%, 1.24%, 2.22% and 0.26 kg in plants infected with SCBV-Kaiyuan, but reducing sugar was increased by 0.21% in infected plants.  相似文献   

10.
 The NS2 gene of Rice stripe virus (RSV) was amplified by RT-PCR, cloned into pGEM-T vector and sequenced. The NS2 gene was inserted into prokaryotic expression vector pET32a to produce recombinant plasmid pET32a-NS2. The recombinant plasmid was introduced into Escherichia coli strain BL21 (DE3) pLysS. SDS-PAGE and Western blot analysis confirmed that NS2 fusion protein was expressed after induction by IPTG. The recombinant NS2 protein was purified with Ni2+-NTA agarose affinity chromatography and the polyclonal antibody against NS2 protein was raised in rabbit. NS2 protein was successfully detected in small brown planthopper (Laodelphax striatellus) at 1:1 600 dilution of the total protein of single planthopper and in infected rice (Oryza sativa) at 1:800 dilution of 10 mg leave by dot immunobinding assay using the polyclonal antibody.  相似文献   

11.
壳寡糖诱导对烟草体内TMV-CP基因表达的抑制作用   总被引:1,自引:0,他引:1  
 采用实时荧光定量PCR方法, 研究了壳寡糖诱导对烟草体内TMV-CP基因表达量的影响。结果表明, 壳寡糖诱导后烟草表达了对TMV侵染的系统获得抗病性, 植株显症推迟4~7 d, 症状减轻, 平均严重度比对照降低了82.9%。同时烟草叶片中CP基因的表达量显著降低。壳寡糖诱导处理的植株在接种病毒时(0 h), CP基因的表达量(拷贝数/2μL)为0.918, 接种后168 h增加到167.730。而在不诱导对照植株内, CP基因的表达量在0 h为1.218, 接种后168 h猛增到648.623。换言之, 不处理对照的表达量在此期间增长了532.53倍, 而壳寡糖诱导处理植株中仅增长了182.71倍。试验证明壳寡糖诱导的系统获得抗病性强烈抑制了烟草体内TMV-CP基因的表达。  相似文献   

12.
Systemic acquired resistance induced in intact ‘Samsun NN’ tobacco plants by either tobacco mosaic virus (TMV) or tobacco necrosis virus (TNV) was more effective against challenge inoculation with the same than with the other of the two viruses. However, in trimmed ‘Samsun NN’ plants resistance induced by either of these viruses was stronger against TMV than against TNV. In intact ‘Samsun’ tobacco plants TNV induced a systemic resistance against itself identical to the one expressed in ‘Samsun NN’. Moreover, it induced systemic resistance against TMV as based on a decrease in TMV content in challeng-inoculated leaves. These observations indicate that systemic acquired resistance is not limited to combinations in which both inducing and challenging virus give rise to a hypersensitive reaction, and further point to virus-specific factors regulating the extent of resistance expressed.  相似文献   

13.
Root colonization by rhizobacteria can induce a systemic resistance in plants that is phenotypically similar to systemic acquired resistance induced by a localized pathogen infection. We used the tobacco–tobacco mosaic virus model to investigate whether the systemic resistance induced by the rhizobacterium Pseudomonas aeruginosa 7NSK2 is mediated by the systemic acquired resistance signal transduction pathway. Experiments with nahG-transformed tobacco revealed that Pseudomonas aeruginosa 7NSK2-induced resistance depended on in planta salicylic acid accumulation for its expression but not for its induction and is, in this respect, similar to systemic acquired resistance. However, Pseudomonas aeruginosa 7NSK2-induced resistance was, unlike systemic acquired resistance, not associated with PR1a expression at the time of challenge with tobacco mosaic virus. This suggests that Pseudomonas aeruginosa 7NSK2 treatment would only potentiate defense gene expression in systemic tissue, which would also explain why its level of resistance is lower than in case of systemic acquired resistance. Because we demonstrated that induced resistance by Pseudomonas aeruginosa 7NSK2 exclusively depends on the production of salicylic acid by this strain our conclusions might also account for other salicylic acid-producing and resistance-inducing rhizobacteria.  相似文献   

14.
植物抗病激活蛋白harpinXooc防治水稻病害的研究   总被引:2,自引:1,他引:2  
植物抗病激活蛋白harpinXooc由水稻条斑病细菌hrp基因簇中hpa1基因编码。用构建于表达载体pET21a(+)上的hpa1诱导表达产物harpinXooc处理烟草,可激发烟草产生过敏反应,以及激活与烟草抗病信号途径相关的基因PR-1a、hin1和hsr203J的表达;处理水稻后,NPR1、OsPR1a、OsPR1b和PAL被激活。表明harpinXooc蛋白与植物互作后,通过水杨酸信号传导途径激活病程相关蛋白等防卫反应基因的转录表达,从而使植物产生系统获得抗病性。harpinXooc经加工后制成含量达1%的可溶性微颗粒制剂在水稻上进行应用,试验结果显示,harpinXooc蛋白可诱导水稻产生抗病性,防治水稻稻瘟病效果与杀菌剂稻瘟必克(三环唑)相当,防治水稻纹枯病和稻曲病效果与井冈霉素效果相当。对水稻增产的效果主要表现在增加粒实重上,增产达6%以上。  相似文献   

15.
枯草芽孢杆菌PTS-394诱导番茄对灰霉病的系统抗性   总被引:5,自引:0,他引:5  
本文研究了枯草芽孢杆菌PTS-394对番茄的防御相关酶活性、抗病信号转导通路的标志基因表达的诱导情况和诱导抗病性对灰霉病的防治效果。结果显示,菌株PTS-394灌根番茄后,在24~72 h内番茄顶端叶片中PAL、PPO、POX、LOX的活性都有不同程度的持续增加,且72 h时达到最高峰值,随后在96 h下降,与对照相比差异显著;此外,番茄抗病信号通路节点基因NPR1和水杨酸(SA)信号通路激发的防卫基因PR-1a,在24~72 h得到了显著持续高表达。以上结果表明,利用菌株PTS-394灌根番茄后,能够诱导植株产生系统抗病性。菌株PTS-394灌根番茄后48 h,离体叶片挑战接种番茄灰霉菌,结果显示,菌株PTS-394处理的番茄叶片病斑面积仅为对照处理的50%,防控效果达47.1%;温室盆栽试验显示,菌株PTS-394处理后对番茄灰霉的防治效果为58.2%。综上所述,枯草芽孢杆菌PTS-394灌根番茄后,可以触发番茄植株系统性的抗病性,增强植株免疫能力。  相似文献   

16.
一种新的90 kD胞外蛋白激发子诱导烟草系统获得抗性研究   总被引:11,自引:4,他引:7  
 就棉疫病菌(Phytophthora boehmeriae Saw.)培养滤液中提纯获得的90 kD胞外蛋白激发子诱发烟草系统获得抗性进行了研究。以10 nmol/L激发子溶液注射处理Samsun NN烟草叶片24 h后,在处理叶片及其上、下各2片叶片接种TMV,结果是处理叶及其上、下各2片叶片上的枯斑数显著少于对照,诱抗防效达40.9%~53.1%;接种TMV7d后处理叶片的枯斑平均直径为1.23mm,显著小于对照叶片上的枯斑直径2.97mm,但是处理叶片的上、下叶片上的枯斑平均直径与对照没有显著差别。以10 nmol/L激发子溶液注射处理Samsun NN烟草叶片分别立即接种或于1、2、4、7、15 d接种TMV,结果证明该激发子诱导烟草对TMV的抗性以处理后第1d至第4 d接种为较好,防效达30.2%~5 0.4%;处理后立即接种和第7d接种TMV诱抗防效仅4%左右,处理叶片上的枯斑数与对照没有显著差别,表明较强的诱导抗性可持续时间<7d。用不同浓度激发子处理烟叶,所测定的0.5~100 nmol/L各浓度均可显著地诱发烟草对TMV产生获得抗性,诱导抗性效果为34.9%~5 8.2%,诱导抗性效果随浓度的降低呈下降趋势。以10 nmol/L激发子溶液注射处理W38烟草叶片,2 d后分别注射接种烟草野火病菌(Pseudomonas syringae pv.tabaci)菌液或喷雾接种烟草赤星病菌(Alternaria alternata)分生孢子,结果是,注射接种烟草野火病菌5d后处理叶片及其上、下叶片上的野火病病斑均显著小于对照;处理叶片上的赤星病病斑数及病斑面积明显小于对照,表明该激发子可诱导烟草对野火病和赤星病产生抗性。上述结果表明,90kD蛋白激发子诱导烟草产生的获得抗性是一种典型的系统获得抗性,该系统获得抗性对病原菌具广谱抗性。  相似文献   

17.
Li JG  Cao J  Sun FF  Niu DD  Yan F  Liu HX  Guo JH 《Phytopathology》2011,101(10):1202-1208
In a previous study, we isolated a new harpin protein, PopW, from the bacterium Ralstonia solanacearum ZJ3721 that can induce a hypersensitive response in tobacco, Nicotiana tabacum, leaves. In the current study, we demonstrate that, in a greenhouse experiment, PopW induced tobacco-acquired resistance against the Tobacco mosaic virus (TMV) with a biocontrol efficacy of 80.9 to 97.4% at a concentration as low as 25 μg/ml in both PopW-treated and neighboring leaves. The resistance induced by PopW is systemic acquired resistance mediated by salicylic acid, which was certified by the development of resistance being accompanied by the expression of the pathogenesis-related-1 gene (PR1) 8 h after PopW was sprayed onto the tobacco leaves. In addition, hydrogen peroxide began to accumulate 10 h after PopW spraying, peaking at 24 h with a maximum concentration of 1.97 μM/g fresh weight. The activities of phenylalanine ammonia lyase (EC4.3.1.5), polyphenoloxidase (EC1.14.18.1), and peroxidase (EC1.11.1.7) also increased, peaking at different times in the PopW-treated tobacco leaves. PopW also reduced the level of TMV disease in field trials with a biocontrol efficacy of 45.2%. Furthermore, PopW both increased tobacco yield (by 30.4 more than in control plants) and improved tobacco foliar quality, with an increase of 50.2% in the number of first-class tobacco leaves from treated compared with untreated plants. All of these results indicate that the new harpin protein PopW has the potential to be an effective biocontrol agent against TMV in tobacco.  相似文献   

18.
Tomato spotted wilt virus (TSWV) is an economically important virus of flue-cured tobacco. Activation of systemic acquired resistance (SAR) by acibenzolar-S-methyl (ASM) in flue-cured tobacco was studied under greenhouse conditions by challenge inoculation with a severe isolate of TSWV. ASM restricted virus replication and movement, and as a result reduced systemic infection. Activation of resistance was observed within 2 days after treatment with ASM and a high level of resistance was observed at 5 days onward. Expression of the pathogenesis-related (PR) protein gene, PR-3, and different classes of PR proteins such as PR-1, PR-3, and PR-5 were detected at 2 days post-ASM treatment which inversely correlated with the reduction in the number of local lesions caused by TSWV. Tobacco plants treated with increased quantities of ASM (0.25, 0.5, 1.0, 2.0, and 4.0 g a.i./7,000 plants) showed increased levels of SAR as indicated by the reduction of both local and systemic infections by TSWV. The highest level of resistance was at 4 g a.i., but this rate of ASM also caused phytotoxicity resulting in temporary foliar spotting and stunting of plants. An inverse correlation between the TSWV reduction and phytotoxicity was observed with the increase of ASM concentration. ASM at the rate of 1 to 2 g a.i./7,000 plants activated a high level of resistance and minimized the phytotoxicity. Use of gibberellic acid in combination with ASM reduced the stunting caused by ASM. Present findings together with previous field experiments demonstrate that ASM is a potential option for management of TSWV in flue-cured tobacco.  相似文献   

19.
本文研究了蛋白Rhp-PSP诱导烟草抗TMV过程中相关防御酶的活性以及丙二醛(MDA)含量的变化,同时测定了抗病相关基因的表达情况。试验证明,蛋白Rhp-PSP处理烟草后,叶片中苯丙氨酸解氨酶(PAL)、过氧化物酶(POD)和多酚氧化酶(PPO)的活性显著提高,但降低了MDA含量。同时基因PR-1、PR-3、PR-5、PDF1.2表达显著上调,证明了蛋白Rhp-PSP具有诱导烟草产生抗TMV的活性。为阐明诱导抗性机制,利用酵母双杂交系统从烟草cDNA文库进行互作蛋白的筛选并验证,结果表明GPI锚定蛋白、VAN3结合蛋白及叶绿素结合蛋白A与蛋白Rhp-PSP互作。  相似文献   

20.
为明确毁灭炭疽菌Colletotrichum destructivum诱抗蛋白诱导烟草的抗病性及其作用,采用喷雾、摩擦接种方法及RT-PCR技术研究了诱抗蛋白的预防保护作用,以及烟草悬浮细胞经诱导后过氧化物酶(POD)、多酚氧化酶(PPO)、苯丙氨酸解氨酶(PAL)活性及脯氨酸(Pro)含量和病程相关基因表达的变化。结果表明,接种3、5和7 d后,该诱抗蛋白对烟草炭疽病的诱抗效果分别为58.00%、48.99%和49.65%,对烟草白粉病的诱抗效果分别为83.26%、80.76%和78.60%,并可以抑制烟草普通花叶病毒的复制及在寄主体内的扩增;经诱抗蛋白处理后,烟草悬浮细胞POD、PPO、PAL活性及Pro含量明显提高;诱抗蛋白能够诱导烟草病程相关蛋白基因PR-1a、PR-1b以及抗病信号传导途径关键基因NPR1的表达。表明毁灭炭疽菌诱抗蛋白可诱导烟草产生抗病性,可能与烟草悬浮细胞中POD、PAL、PPO的活性及Pro的含量提高以及相关病程基因表达有关。  相似文献   

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