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1.
Sugar accumulation in tobacco plants systemically protected against blue mold (Peronospora tabacina)
A two- to threefold increase in total soluble sugar content was detected in the leaves of tobacco plants(Nicotiana tabacum L.) 24 days after stem inoculation with conidia ofPeronospora tabacina (=Peronospora hyoscyami f. sp.tabacina), relative to leaves of non-inoculated control plants. Glucose and fructose accounted for most of this increase. The leaves of the inoculated plants were also protected against blue mold incited byP. tabacina. The increased sugar content may be due to the three- to fourfold increase in activity of (β-1,3 glucanase in the leaves and/or to the threefold increase in activities of β-1,3 glucanase, invertase and amylase in the inoculated sems. Tobacco leaf discs floated on glucose or other mono- and disaccharides at 55.5 mM, but not on polyethyleneglycol at a similar osmotic potential, reacted hypersensitively upon challenge withP. tabacina. 相似文献
2.
Deanna L. Funnell Christopher B. Lawrence Jeffrey F. Pedersen Christopher L. Schardl 《Physiological and Molecular Plant Pathology》2004,65(6):285-296
Systemic acquired resistance (SAR) is induced following inoculation of Peronospora tabacina sporangia into the stems of Nicotiana tabacum plants highly susceptible to the pathogen. Previous results have shown that accumulation of acidic β-1,3-glucanases (PR-2's) following induction of SAR by P. tabacina may contribute to resistance to P. tabacina. We showed that up-regulation of the PR-2 gene, PR-2d, following stem inoculation with P. tabacina, is associated with SAR. Studies using plants transformed with GUS constructs containing the full length promoter from PR-2d or promoter deletions, provided evidence that a previously characterized regulatory element that is involved in response to salicylic acid (SA), may be involved in regulation of PR-2d following induction of SAR with P. tabacina. This work provides evidence that regulation of PR-2 genes during P. tabacina-induced SAR may be similar to regulation of these genes during infection of N-gene tobacco by TMV or following exogenous application of SA, and provides further support for the role of SA in regulation of genes during P. tabacina-induced SAR. 相似文献
3.
Studies on polymer size, concentration and mode of application, either as foliar spray or soil drench, in relation to the induction of resistance to tobacco mosaic virus (TMV) in Nicotiana tabacum cv xanthi-nc by poly(acrylic acid) (PA) are reported. PA also induced resistance to TMV in N. glutinosa, to pelargonium leaf curl virus in Datura stramonium, to cucumber mosaic virus in Vigna sinensis and to tobacco ring-spot virus in N. tabacum cv White Burley. No TMV was detected in PA-treated tomato cv Virocross 11 days after inoculation; but the susceptible cultivar Craigella became infected. PA treatment had no effect on TMV replication in White Burley tobacco but resistance was induced to Peronospora tabacina, a fungal pathogen of N. tabacum cv xanthi-nc. The potential of PA-induced resistance as a control measure for viruses and fungi is discussed. 相似文献
4.
Moshe Reuveni Sadik Tuzun James S. Cole Malcolm R. Siegel William C. Nesmith Joseph Ku 《Physiological and Molecular Plant Pathology》1987,30(3)
Dipping leaf strips of greenhouse or field-grown tobacco (Nicotiana tabacum L., cv. Ky-14) plants into acetone for 1 s, prior to inoculation with sporangia of Peronospora tabacina Adam, increased their susceptibility to blue mold. Disease severity and sporangial production on leaf discs from acetone-treated leaves were markedly increased compared to those on discs from untreated leaves. Treatment with acetone also decreased variation in susceptibility of leaves from plants of various ages. Disease severity on discs obtained from attached leaves which were dipped in acetone for 1 s was three times greater up to 15 days after dipping than on discs from leaves that were not dipped. TLC and GLC analyses of the acetone extracts indicated that 95% or more of the major cuticular diterpenoids, α- and β-4,8,13-duvatriene-1,3-diols (DVT), were removed from the surface by dipping for 1 s. These compounds had not reappeared on the leaf surface 15 days after leaves were dipped in acetone for 1 s. Aqueous suspensions of the acetone-soluble constituents as well as authentic DVT, inhibited sporangial germination of P. tabacina (ED100 = 25 ppm) and the antifungal activity was accounted for by DVT. When DVT was removed from a leaf surface and added back to the same leaf strip, the resistance of the leaf tissue was restored. As tobacco plants aged, their susceptibility to blue mold decreased and the quantity of DVT on the leaf surface increased. The data support a role for DVT in the resistance of tobacco against blue mold. 相似文献
5.
Tobacco becomes naturally resistant to blue mould caused by Peronospora tabacina as it ages. This age-related resistance is correlated to the time of normal floral development and the senescence of lower leaves: however, it is dependent on neither. β-1,3-Glucanase, chitinase and peroxidase activities increase in tobacco with age. These increases correlate with the development of age-related resistance to blue mould and were independent of floral development. Additionally. β-1,3-glucanase, chitinase, and peroxidase activities were higher in leaf tissue from the main stalk resistant to blue mould) as compared to leaf tissue from suckering stems (susceptible to blue mould) on the same plant. Isozyme patterns of β-1,3-glucanase and chitinase in all resistant tissues are typical of those of tissues systemically protected by either stem injection with Peronospora tabacina or foliar inoculation with TMV. 相似文献
6.
激活蛋白PeaT1诱导烟草对TMV的系统抗性 总被引：4，自引：0，他引：4
枯斑三生烟草(Samsun-NN)经激活蛋白PeaT1诱导后接种烟草花叶病毒(Tobacco mosaic virus,TMV),对TMV产生了明显的系统获得抗性,枯斑抑制率达54.15%,枯斑大小也受到一定程度的限制。研究结果表明,PeaT1处理烟草植株下位三片叶不同时间后,其上部叶片中PPO、POD和PAL 3种抗病防御酶活性均比对照提高,第4 d酶活性达到最高值。实时荧光定量PCR检测结果显示,经PeaT1诱导4 d后烟草叶片中抗病相关基因PR1a、PR1b、NPR1在转录表达水平上较未诱导对照都有不同程度的上调。由以上结果我们推测PeaT1诱导烟草产生了系统获得抗性,本研究为进一步阐明PeaT1诱导植物抗病的信号传导途径奠定了基础。 相似文献
7.
L. C. van Loon Jeanne Dijkstra 《European journal of plant pathology / European Foundation for Plant Pathology》1976,82(6):231-237
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
8.
Two bioassay methods are described which use detached tobacco leaves to measure the sensitivity of Peronospora tabacina to systemic fungicides. Tobacco leaves (13–15 cm2), treated with fungicides before or after detachment from the plant, were inoculated with sporangia in water drops and, after incubation in beakers and Petri plates, the disease severity and/or production of sporangia was determined 4–7 days after treatment with the fungicides. Of 15 systemic fungicides applied to detached leaves, eight N-phenylamides at 0.066?1.0 μg ml?1 controlled blue mould; metalaxyl was the most effective fungicide. Isolates of P. tabacina, collected in the field from tobacco plants grown in soil treated with metalaxyl, were not resistant to the fungicide applied to detached leaves prior to inoculation. The fungicide, applied to leaves before detachment, was used to measure the efficacy of five systemic N-phenylamide fungicides sprayed on the basal and unsprayed distal portions of the leaves. Blue mould was controlled on the basal portion of the leaf by all the fungicides at 0.66?1.0 μg ml?1, but it required the application of 3–30 times more chemical on the basal portion to achieve comparable blue mould control on the distal part of the leaf. 相似文献
9.
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
10.
Jeanne Dijkstra G. C. A. Bruin Ankie C. Burgers L. C. Van Loon Christien Ritter P. A. C. M. Van De Sanden D. Hendrina Wieringa-Brants 《European journal of plant pathology / European Foundation for Plant Pathology》1977,83(2):41-59
Since July 1974Nicotiana tabacum ‘Samsun NN’ plants, inoculated with the common strain of tobacco mosaic virus (TMV), have occasionally been found to develop necrosis on non-inoculated upper leaves 2–7 days after the local necrotic lesions had appeared on the lower leaves. All these plants had been kept in a growth chamber at 17–20°C. Other tobacco species and cultivars carrying theN gene, such asN. glutinosa andN. tabacum ‘Xanthi-nc’, showed the same phenomenon. Substantial amounts of TMV could be recovered from leaves with systemic symptoms. The systemic necrosis somewhat resembled that caused by tobacco rattle virus (TRV). A number of possible causes, such as high concentration of the inoculum, contamination with another strain of TMV or with TRV, change in the genetic composition of the host plants and certain growing conditions (soil, water, pesticides) were investigated. None of these factors could be held fully responsible for the abnormal systemic reaction, although there was evidence that the soil could sometimes play an important rôle. 相似文献
11.
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
12.
Moshe Reuveni Reuven Reuveni 《European journal of plant pathology / European Foundation for Plant Pathology》2000,106(7):633-638
A spray inoculation of the first leaf of 2-leaf stage cucumber plants with a non-pathogenic isolate of Alternaria cucumarina or Cladosporium fulvum before a challenge inoculation with the pathogen Sphaerotheca fuliginea induced systemic resistance to powdery mildew on leaves 2–5. Systemic resistance was expressed by a significant (p < 0.05) reduction in the number of powdery mildew colonies produced on each leaf of the induced plants, as compared with water-sprayed plants. Systemic resistance was evident when a prior inoculation with each of the inducing fungi was administered 1, 3 or 6 days before the challenge inoculation with S. fuliginea. Increasing the inoculum concentration of A. cucumarina or C. fulvum enhanced the systemic protection and provided up to 71.6% or 80.0% reduction, respectively, in the number of colonies produced on upper leaves, relative to controls. Increasing the inoculum concentration of S. fuliginea used for challenge inoculation, increased the number of powdery mildew colonies produced on both induced and non-induced plants. Pre-treated plants, however, were still better protected than controls, indicating that the level of systemic protection was related to the S. fuliginea inoculum concentration. The induction of systemic resistance against powdery mildew by biotic agents, facilitates the development of a wide range of disease management tools. 相似文献
13.
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
14.
将编码大豆凝集素的lec-s基因插入植物表达载体pBI121中,构建植物重组表达质粒pBI121:: lec-s。由根癌土壤杆菌EHA105介导的叶盘法转化烟草,获得了转基因烟草株系。PCR和RT-PCR检测证明lec-s基因已转入烟草植株中。接种烟草花叶病毒（Tobacco mosaic virus,TMV）进行抗病性试验结果表明,转基因烟草叶片上的病斑数显著减少,说明转基因烟草表现出对TMV的抗性。定量RT-PCR检测发现,接种TMV后,抗病防卫基因（PR-1a、GST1、Pal和hsr515）在转基因烟草叶片中显著上调表达。这些结果表明,大豆凝集素基因lec-s转化烟草可对TMV产生抗性,其作用机制可能在于lec-s基因参与了植物的防卫信号通路,诱导了抗病防卫基因在转基因植株体内的表达,增强了植株对TMV的系统抗性。 相似文献
15.
Saccharin-induced protection against powdery mildew in barley: effects on growth and phenylpropanoid metabolism 总被引：1，自引：0，他引：1
Treatment of barley ( Hordeum vulgare ) with 3 m m saccharin, applied as a foliar treatment to the first leaf or as a soil drench, provided significant control of powdery mildew ( Blumeria graminis f.sp. hordei ) on first and second leaves. This was unlikely to be the result of a direct effect of saccharin on the fungus, as application of the chemical to first leaves 2 h before inoculation did not affect conidial germination or formation of appressoria. Saccharin treatment had no significant effect on plant growth, except for a reduction in total leaf area in plants treated with a saccharin drench 14 days before inoculation with mildew. Phenylalanine ammonia-lyase activity was reduced significantly in second leaves 18 and 48 h after inoculation in plants treated with saccharin 14 days earlier. Peroxidase activity increased significantly in plants challenged with mildew within 6 days of saccharin application, although changes were not apparent until 48 h after pathogen challenge. On these occasions, treatment with saccharin resulted in a 33% increase in peroxidase activity compared with controls. In plants inoculated 10 or 14 days after saccharin application, cinnamyl alcohol dehydrogenase (CAD) activity increased prior to, and 18, 24 and 48 h after, inoculation of the barley plants with mildew. CAD activity increased approximately twofold compared with controls. However, in contrast to peroxidase, CAD activity was significantly higher in saccharin-treated plants prior to and after inoculation with powdery mildew, suggesting that saccharin primes CAD activity prior to pathogen challenge. 相似文献
16.
17.
Masayuki FUJIWARA Miyuki SAKAGUCHI Bo-Song RYAN Satoshi T OHKI Takeshi OSAKI 《Journal of General Plant Pathology》2001,67(2):159-163
Local lesion formation on cowpea leaves was more than 50% inhibited by treatment with a 23 kDa RNase-like glycoprotein from
Cucumis figarei, figaren, from 24 hr before to 1 hr after inoculation with Cucumber mosaic virus (CMV). CMV accumulation detected by ELISA in tobacco leaves treated with figaren 6 or 0 hr before inoculation with CMV was
suppressed. When upper leaves of tobacco plants were treated with figaren and inoculated 10 min later with CMV, mosaic symptoms
were delayed for 5–7 days on most of the tobacco plants, and some plants remained asymptomatic. From fluorescence in situ hybridization, infection sites were present in figaren-treated cowpea or melon leaves after inoculation with CMV, though the
sites were reduced in number and size compared with those in water-treated control leaves. The amount of CMV RNAs and CMV
antigen in melon protoplasts inoculated with CMV and subsequently incubated with figaren similarly increased with time as
did that in the control. ELISA and local lesion assays indicated that CMV infection on the upper surfaces of the leaves of
tobacco, melon, cowpea and C. amaranticolor whose lower surfaces had been treated with figaren 5–10 min before CMV inoculation was almost completely inhibited. Figaren
did not inhibit CMV infection on the opposite untreated leaf halves of melon, cowpea and C. amaranticolor, whereas it almost completely inhibited CMV infection on the untreated halves of leaves of tobacco. CMV infection was not
inhibited in the untreated upper or lower leaves of the four plants. These data suggest that figaren does not completely prevent
CMV invasion but does inhibit the initial infection processes. It may also induce localized acquired resistance in host plants.
Received 10 October 2000/ Accepted in revised form 6 February 2001 相似文献
18.
P. Vidhyasekaran N. Kamala A. Ramanathan K. Rajappan V. Paranidharan R. Velazhahan 《Phytoparasitica》2001,29(2):155-166
When lower leaves of rice plants were inoculated with powder formulation of a saprophytic strain ofPseudomonas fluorescens, Pfl, upper leaves, in addition to the inoculated lower leaves, showed resistance to the rice bacterial blight pathogenXanthomonas oryzae pv.oryzae. When the leaves were challenge-inoculated withX. oryzae pv.oryzae 4 days afterP. fluorescens application on lower leaves, the disease intensity in upper leaves decreased from 6.7 to 1.1. When rice seeds were treated
with the formulation ofP. fluorescens Pfl and sown, 30-day-old seedlings showed resistance toX. oryzae pv.oryzae and the disease intensity decreased from 6.8 to 1.2. The induced resistance was transient; leaves sprayed withP. fluorescens Pfl at 30 days after treatment and leaves of 60-day-old seedlings fromP. fluorescens-treated seeds did not show resistance to the pathogen. In field trials, seed treatment followed by foliar application of the powder
formulation ofP. fluorescens Pfl effectively controlled rice bacterial blight and increased the yield. In the induced resistant leaves a sharp increase
in lignification and activities of peroxidase, phenylalanine ammonia-lyase and 4-coumarate: CoA ligase was observed when the
leaves were challenge-inoculated withX. oryzae pv.oryzae. An approximately threefold increase in lignin content, peroxidase activity and phenylalanine ammonia-lyase activity and a
fivefold increase in 4-coumarate: CoA ligase activity were observed 5 days after challenge inoculation withX. oryzae pv.oryzae in rice leaves pretreated withP. fluorescens for 5 days. A similar increase in defense-related activities was not observed in susceptible interactions or inP. fluorescens-treated plants at later stages of interactions when no resistance to the pathogen was observed. 相似文献
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20.
耐病毒诱导剂88-D诱导珊西烟产生PR蛋白及对TMV侵染的抗性 总被引：8，自引：0，他引：8
耐病毒诱导剂88-D注射于珊西烟(Nicotiana tabacum var Xanthi nc)下部叶片,上部叶片接种TMV,结果耐病毒诱导剂88-D诱导上部未注射叶片对TMV侵染的抗性,对侵染的抑制率为62.95~82.86%。对耐病毒诱导剂88-D处理叶片及上部未处理叶片细胞间液中的PR蛋白(Pathogenesis-related Proteins)进行电泳分析,结果表明耐病毒诱导剂88-D可系统地诱导珊西烟产生9种健康植株所没有的PR蛋白。PR蛋白的诱导与抗病性、耐病性的诱导相一致。 相似文献