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1.
Polygalacturonase-inhibiting protein (PGIP) from Japanese pear: possible involvement in resistance against scab 总被引:4,自引:0,他引:4
Mohamed Faize Tomoko Sugiyama Lydia Faize Hideo Ishii 《Physiological and Molecular Plant Pathology》2003,63(6):319-327
Venturia nashicola is the causal agent of scab, a fungal disease affecting Asian pears. The Japanese pear cv. ‘Kousui’ is highly susceptible to the race 1 of this fungus whereas the cv. ‘Kinchaku’ and the non-host European pear cv. ‘Flemish Beauty’ are resistant. The aim of this work is to investigate the role of polygalacturonase-inhibiting proteins (PGIPs) of pear during the interactions with V. nashicola leading to susceptibility or resistance. PGIP protein was detected from immature fruit of Kousui and Kinchaku. It showed a molecular mass of 42 kDa that shifted to 35 kDa after chemical deglycosylation. The gene pgip was amplified by PCR using genomic DNA and/or cDNA from young leaves of Kousui, Kinchaku, and European pear cvs. Flemish Beauty, ‘Bartlett’, and an Asian wild pear strain ‘Mamenashi 12’, then sequenced after sub-cloning. Some conserved variations were identified in the sequence indicating that gene family also exists in pgip of Japanese pear and confirmed by Southern blot analysis. The expression of PGIP was studied in scab-inoculated leaves of the susceptible Kousui and the resistant Kinchaku and Flemish Beauty. pgip Gene and its encoding protein were highly and rapidly activated in these resistant plants. In addition, PGIP extracts derived from Kinchaku and Flemish Beauty partially inhibited the activity of polygalacturonase (PG) from V. nashicola suggesting a possible role of PGIP in limiting fungal growth frequently observed in these resistant cultivars. 相似文献
2.
Mayumi Egusa Haruna Ochi Takashi Tsuge Hiroshi Otani Motoichiro Kodama 《Journal of General Plant Pathology》2009,75(2):119-124
The Japanese pear pathotype of Alternaria alternata, a toxin-dependent necrotrophic pathogen, causes black spot of Japanese pear by producing the host-specific AK-toxin. Pre-inoculation
with nonpathogenic A. alternata or pretreatment with an elicitor prepared from A. alternata reduced disease symptoms caused by the pathogen. Salicylic acid- and jasmonic acid-dependent signaling pathways are not involved
in the induced resistance to infection by the pathogen. The expression of multiple defense-related genes in Japanese pear
leaves inoculated with nonpathogenic A. alternata was examined using suppression subtractive hybridization.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank database as accessions DC993229–DC993535. 相似文献
3.
Naoki Eguchi Hirofumi Tokutake Naho Yamagishi 《Journal of General Plant Pathology》2008,74(5):382-389
Hot water was dripped into the rhizosphere of Japanese pear trees (Pyrus serotina Rehd. grafted on P. betulifolia Bunge.) infested with the white root rot fungus Rosellinia necatrix Prillieux, to destroy the fungus. Isolates of R. necatrix from diseased roots of Japanese pear were vulnerable to water at temperatures above 35°C, and the fungus was eradicated from
the colonized substrate when water at 35°C was provided for 3 days. The time required to eradicate R. necatrix decreased exponentially with increasing temperature. Japanese pear trees tolerated a temperature of 45°C without reduction
in vigor. Field experiments demonstrated the practical use of hot water drip irrigation (HWD). HWD at 50°C completely destroyed
white root rot mycelia on diseased roots, and many rootlets grew after the treatment. HWD at this temperature caused no injury
to the trees. HWD of diseased orchard trees was assessed in Takamori and Iida in southern Nagano, Japan. The fungus recurred
in two of four trees 28 months after treatment in Takamori and in two of ten trees 16 months after treatment in Iida. The
new mycelia emerged on thick roots deep within the soil. Although there is a possibility of recurrence, HWD treatment is a
practical control measure for white root rot. 相似文献
4.
Proliferation and collapse of subcuticular hyphae of Venturia nashicola race 1 were studied ultrastructurally, after inoculation of susceptible Japanese pear cv. Kousui, resistant Japanese pear
cv. Kinchaku, resistant Asian pear strain Mamenashi 12 and nonhost European pear cv. Flemish Beauty leaves, to understand
the nature of the resistance mechanism. After cuticle penetration by the pathogen, the hyphae were observed at lower frequency
in epidermal pectin layers and middle lamellae of leaves of the three resistant plants than in those of susceptible ones.
This result suggested that fungal growth was suppressed in the incompatible interaction between pear and V. nashicola race 1. In the pectin layers of all inoculated plants, some hyphae had modifications such as breaks in the plasmalemma with
plasmolysis, necrotic cytoplasm and degraded cell walls. More hyphae had collapsed in the leaves of the three resistant plants
than in those of the susceptible cv. Kousui. In collapsed hyphae, the polymerized cell walls broke into numerous fibrous and
amorphous pieces, showing that the scab resistance might be associated with cell wall-degrading enzymes from pear plants. 相似文献
5.
A severe crown rot of pear trees of cultivar ‘Kondoula’ grafted on quince rootstock was observed in Greece. Isolations from
the affected tissues repeatadly yielded aPhytophthora sp. that was determined by morphological and physiological characteristics to beP. citrophthora. The pathogenicity of two of theP. citrophthora isolates was tested by inoculating trunks of 2-year-old pear trees by mycelial agar disks. Thirty-two days after inoculation
all inoculated trees were infected. Although the pear isolates could not be differentiated from isolates ofP. palmivora orP. nicotianae based on isozyme profiles of α-esterase or lactate dehydrogenase, RAPD profiles with one selected primer differentiated the
pear isolates from the other species and revealed an electrophoretic banding pattern similar to that of aP. citrophthora standard. This is the first report ofP. citrophthora on pear trees in Greece. 相似文献
6.
We investigated the diurnal pattern of ascospore discharge of the Japanese pear scab fungus (Venturia nashicola Tanaka & Yamamoto) in an orchard. Ascospores of V. nashicola were mainly discharged during the day. Most ascospores were discharged from 7:00 to 19:00: 99.6% in 2001, 99.3% in 2002,
and 93.8% in 2005. Because the ascospores were discharged only when the fallen diseased leaves were wet from precipitation,
the wetness of these leaves is probably imperative for spore discharge. Ascospore discharge began immediately after precipitation
in the daytime. When it rained at night, however, ascospore discharge did not begin until the following morning and never
began immediately after precipitation. We also investigated other meteorological factors. When fallen diseased leaves were
wet, the percentage of ascospore discharge was positively correlated with the amount of solar radiation and atmospheric temperature
and negatively correlated with relative humidity. Ascospore discharge was interrupted by a decrease in solar radiation and
atmospheric temperature and by increased relative humidity at night. This report is the first that V. nashicola discharges ascospores primarily during the day. 相似文献
7.
Jürgen Köhl Belia Groenenboom-de Haas Helen Goossen-van de Geijn Adrianus Speksnijder Pieter Kastelein Sybren de Hoog Bert Gerrits van den Ende 《European journal of plant pathology / European Foundation for Plant Pathology》2009,124(1):151-162
Stemphylium vesicarium (teleomorph: Pleospora herbarum) is the causal agent of brown spot disease in pear. The species is also able to cause disease in asparagus, onion and other
crops. Saprophytic growth of the fungus on plant debris is common. The objective of this study was to investigate whether
isolates of S. vesicarium from different hosts can be pathogenic to pear. More than hundred isolates of Stemphylium spp. were obtained from infected pear fruits, dead pear leaves, dead grass leaves present in pear orchard lawns as well as
from necrotic leaf parts of asparagus and onion. Only isolates originating from pear orchards, including isolates from dead
grass leaves, were pathogenic on pear leaves or fruits in bioassays. Non-pathogenic isolates were also present in pear orchards.
Stemphylium vesicarium from asparagus or onion, with one exception, were not pathogenic to pear. Analysis of the genetic variation between isolates
using Amplified Fragment Length Polymorphism (AFLP) showed significant concordance with host plants. Isolates from asparagus
or onion belonged to clusters separate from the cluster with isolates from pear or grass leaves collected in pear orchards.
Multilocus sequencing of a subset of isolates showed that such isolates were similar to S. vesicarium. 相似文献
8.
9.
Ultrastructural study on acibenzolar-S-methyl-induced scab resistance in epidermal pectin layers of Japanese pear leaves 总被引:1,自引:0,他引:1
The infection behavior of Japanese pear scab pathogen Venturia nashicola race 1 was studied ultrastructurally in acibenzolar-S-methyl (ASM)-pretreated susceptible Japanese pear (cv. Kousui) leaves to determine the mechanism of ASM-induced scab resistance. On ASM-pretreated leaf surfaces, the infection behavior (conidial germination and appressorial formation) was similar to that on distilled water (DW)-pretreated leaves prior to cuticle penetration by the pathogen. However, after penetration, differentiated behavior was found in epidermal pectin layers and middle lamellae of the ASM-pretreated leaves. Subcuticular hyphae in epidermal pectin layers and middle lamellae of ASM-pretreated pear leaves were observed at lower frequency than in DW-treated leaves. The results indicated that fungal growth was suppressed in ASM-pretreated pear leaves. In the pectin layers of ASM- and DW-pretreated leaves, some hyphae showed morphological modifications, which were used as criteria to judge collapse of hyphal cells, including plasmolysis, necrotic cytoplasm, and cell wall destruction. More hyphae had collapsed in ASM-pretreated leaves than in DW-treated ones. In addition, the cell walls of collapsed hyphae broke into numerous fibrous and amorphous pieces, suggesting that ASM-induced scab resistance might be associated with cell-wall-degrading enzymes from pear plants. In addition, results from morphometrical analysis suggested that the activity or production of pectin-degrading enzyme from hyphae were inhibited by ASM application when compared with DW treatment. 相似文献
10.
11.
Evelyn Aigho?Aremu Tamotsu?Furumai Yasuhiro?Igarashi Yukio?Sato Hajime?Akamatsu Motoichiro?Kodama Hiroshi?Otani
Fistupyrone (FP), a metabolite from Streptomyces sp. TP-A0569, inhibited the in vivo infection of Chinese cabbage seedlings by Alternaria brassicicola. To detect the possible action sites of FP, the effect of FP on the infection behavior of A. brassicicola and A. alternata was investigated. When spores of A. brassicicola were suspended in FP solution and inoculated on host leaves, FP at 0.1ppm significantly inhibited spore germination, appressorial formation, and infection hypha formation of A. brassicicola. Host-specific AB-toxin production and lesion formation by A. brassicicola spores were also reduced significantly by treatment with FP 1ppm. The effect of FP seemed to be irreversible because significant washing of FP-treated spores with distilled water (DW) did not change the inhibitory effects. In contrast, A. alternata isolates such as Japanese pear pathotype, apple pathotype, and saprophyte behaved almost equally in both FP- and DW-treated spores. Mycelial dry weight in potato dextrose broth and mycelial diameters on potato dextrose agar, gelatin glucose agar, and Czapek solution agar of both A. brassicicola and A. alternata were not different with or without addition of FP. These results indicate that FP at low concentrations has a fungicidal effect on spores of A. brassicicola but not on spores of A. alternata; FP also does not affect the vegetative phase of these fungi. 相似文献
12.
Naoto Shimizu Naoki Hosogi Gang-Su Hyon Shan Jiang Kanako Inoue Pyoyun Park 《Journal of General Plant Pathology》2006,72(1):6-15
AK-toxin I caused plasma membrane modifications with plasma membrane-derived membrane fragments only in sensitive Japanese
pear tissues. H2O2 generation was abundant in both the membrane fragments and the plasma membranes of the toxin-treated sensitive tissues. Whether
lipid peroxidation was induced in plasma membranes of the toxin-treated sensitive tissues was examined biochemically and histochemically.
Lipid peroxidation was caused only in the toxin-treated sensitive tissues or the toxin-treated plasma membrane-enriched fractions
from sensitive young pear fruits. The results indicated that the peroxidation was probably induced by reactive oxygen species
in the modified plasma membranes by action of toxin, suggesting that peroxidation is closely associated with plasma membrane
modifications. 相似文献
13.
Monoconidial strains of Venturia nashicola Tanaka et Yamamoto were isolated from Japanese or Chinese white pear trees which had never been treated with sterol demethylation inhibitors (DMIs) and their baseline sensitivities to fenarimol were determined by mycelial growth tests on fungicide-amended culture media. Strains were also obtained from Japanese pear orchards, which had been intensively treated with DMIs for several years and monitored for the shifts of fenarimol sensitivity in comparison with the baseline sensitivity. Results suggested slight shifts to lower fenarimol sensitivity in strains isolated from DMI-treated Japanese pear orchards. However, in inoculation tests on pear seedlings, fenarimol still provided adequate control of V. nashicola strains with reduced sensitivity to fenarimol in vitro, suggesting that the performance of this fungicide will still be maintained in the field. © 1998 Society of Chemical Industry 相似文献
14.
Induced Resistance of Acibenzolar-S-methyl (CGA 245704) to Cucumber and Japanese Pear Diseases 总被引:8,自引:0,他引:8
Hideo Ishii Yasunori Tomita Takeshi Horio Yoshihiro Narusaka Yasuhiko Nakazawa Kumiko Nishimura Susumu Iwamoto 《European journal of plant pathology / European Foundation for Plant Pathology》1999,105(1):77-85
Antifungal activity of the novel compound acibenzolar-S-methyl (CGA245704: benzo[1,2,3]thiadiazole-7-carbothioic acid S-methyl ester) was examined in vitro. No remarkable activity was observed on mycelial growth and conidial germination of almost all fungi tested. Only melon isolates of Didymella bryoniae were sensitive to this compound. On potted plants, acibenzolar-S-methyl showed control efficacy on anthracnose and scab of cucumber and rust of Japanese pear but not on Fusarium wilt of cucumber. In field trials, the occurrence of both rust and scab on Japanese pear was suppressed with this compound. Based on these experiments, it was suggested that acibenzolar-S-methyl induced resistance to some but not all diseases on cucumber and Japanese pear. Induction of disease resistance in cucumber was rapidly triggered after treatment with acibenzolar-S-methyl. 相似文献
15.
Kuko Fuke Kana Takeshita Nanako Aoki Toshiyuki Fukuhara Mayumi Egusa Motoichiro Kodama Hiromitsu Moriyama 《Journal of General Plant Pathology》2011,77(4):248-252
Strains of the Japanese pear pathotype of Alternaria alternata were screened for double-stranded RNAs (dsRNAs). Four strains had several dsRNAs; strain N18 was associated with several
dsRNAs and had impaired growth phenotypes such as irregular mycelium and abnormal pigmentation. We isolated dsRNA-cured isolates
from strain N18 by single-conidium isolation. The dsRNA-cured isolates had recovered normal growth and pigmentation. Enlarged
vesicles were observed in mycelial cells of the original dsRNA-carrying N18 strain. DAPI nuclear staining revealed regression
of the nuclei in dsRNA-carrying N18 cells. These results indicate that the dsRNAs might have negative effects, such as apoptosis-like
cell death, on the host fungus. 相似文献
16.
Takeshi Shinogi Tomoko Suzuki Takayuki Kurihara Yoshihiro Narusaka Pyoyun Park 《Journal of General Plant Pathology》2003,69(1):7-16
Reactive oxygen species (ROS) generation was examined in the interaction of Alternaria alternata Japanese pear pathotype and host plants using three methods: nitro blue tetrazolium (NBT) method for microscopic detection
of O2
−, diaminobenzidine (DAB) methods for microscopic detection of H2O2, and cerium chloride methods for ultrastructural detection of H2O2. ROS generation was detected by NBT and DAB methods at appressoria on leaves of susceptible cultivars and heat-shocked leaves
of resistant cultivars but not in leaves of resistant cultivars. Ultrastructural detection by the cerium chloride method identified
ROS generation at cell walls of appressoria and penetration pegs in susceptible, resistant leaves and heat-shocked leaves.
These differences in the ultrastructural and microscopic data in resistant areas were due to the restriction of ROS generation
in limited areas, the side facing the plant surface, of appressoria and penetration pegs. Therefore, ROS generation was apparently
induced regardless of the resistance or susceptibility of the cultivar with the difference being in the volumes generated.
After evaluating the pathological role of ROS generation in fungal structures, such generation was found to be associated
with early penetration of cell walls in pear plants. Additionally, ROS generation in plants was also found in degrading pectin
layers near infected hyphae and in plasma membrane modification sites in susceptible leaves but not in resistant leaves. ROS
generation in susceptible leaves might be accompanied with plasma membrane damage, although the role of ROS generation in
the pectin layers is not clear. ROS generation in both fungal and plant cells during their interaction was likely associated
with the expression of susceptibility.
Received: June 3, 2002 / Accepted: July 31, 2002 相似文献
17.
The efficacy of N -phenylcarbamates and N -phenylformamidoximes against benzimidazole-resistant strains of Venturia nashicola was tested experimentally in Japanese pear orchards. Both compounds gave effective control when applied in an orchard where highly benzimidazole-resistant strains were predominant. However, unsatisfactory control was observed in an orchard where the fungal population was dominated by fungal strains with intermediate or weak benzimidazole resistance. Strains resistant to N -phenylcarbamates and N -phenylformamidoximes were widely distributed in Japanese pear orchards, suggesting that effective use of these compounds to control benzimidazole-resistant strains of V. nashicola would not be practicable. Increased sensitivity to N -phenylformamidoximes in highly benzimidazole-resistant isolates was shown to be controlled by a single chromosomal gene, but progenies that were highly resistant to both a benzimidazole fungicide and a N -phenylformamidoximes appeared in crosses between parents resistant to each fungicide alone. Similar strains were also found in pear orchards, and this'double resistance'was shown to be heritable. 相似文献
18.
库尔勒香梨主要病毒多重RT-PCR检测技术研究 总被引:10,自引:1,他引:10
利用nad5基因作为内标系统,研究建立了库尔勒香梨上苹果茎痘病毒(ASPV)、苹果褪绿叶斑病毒(ACLSV)和苹果茎沟病毒(ASGV)等的RT-PCR检测技术,在此基础上研究建立了库尔勒香梨多重RT-PCR内标检测系统。并对回收的特异片段进行了克隆、鉴定和测序。测序结果表明:库尔勒香梨上的ACLSV与GenBank中D14996序列(日本苹果上的ACLSV分离物)中的6860~7536bp片段有116个碱基的差异,序列相似性为83.75%;库尔勒香梨上的ASPV与GenBank中D21828序列(德国梨脉黄病毒相关分离物)中的8869~9238bp片段有72个碱基的差异,序列相似性为79.5%;库尔勒香梨上的ASGV与GenBank中AB004063序列(日本ASGV分离物)中的6039~6311bp片段有21个碱基的差异,序列相似性为92.3%。 相似文献
19.
Yansu Song Ni Hong Liping Wang Hongju Hu Rui Tian Wenxing Xu Fang Ding Guoping Wang 《European journal of plant pathology / European Foundation for Plant Pathology》2011,130(2):183-196
Apple chlorotic leaf spot virus (ACLSV) isolates from sand pear (Pyrus pyrifolia) were characterized by analyzing the sequences of their coat protein (CP) genes and serological reactivity of recombinant
coat proteins (rCPs). The sequences of CP genes from 22 sand pear isolates showed a high divergence, with 87.3–100% identities
at the nucleotide (nt) level and 92.7–100% identities at the amino acid (aa) level. Phylogenetic analysis on the aa sequence
of CP showed that the analyzed ACLSV isolates fell into different clusters and all isolates from sand pear were grouped into
a large cluster (I) which was then divided into two sub-clusters (A and B). Sodium dodecylsulfate-polyacrylamide gel electrophoresis
(SDS-PAGE), western blot and enzyme-linked immunosorbent assay (ELISA) analyses demonstrated that rCPs of eight ACLSV isolates
(PP13, PP15-2, PP24, PP43, PE, PP54, PP56 and ACLSV-C) from two sub-clusters had different mobility rates and serological
reactivity. The rCPs of five isolates grouped into the sub-cluster A showed stronger reactivity with antibodies against rCPs
of a sand pear isolate ACLSV-BD and virions of a Japanese apple isolate P-205 than that with the antibody against a Chinese
apple isolate ACLSV-C. Three isolates grouped into the sub-cluster B showed stronger reactivity with the antibody against
ACLSV-C. The antigenic determinants of CPs from these eight isolates and isolates ACLSV-BD and P-205 were predicted. These
results contribute to a further understanding of molecular diversity of the virus and its implication in serological detection. 相似文献
20.
The pathogenicity and taxonomy of 15 isolates of Alternaria spp. from pear and apple were compared. Only isolates from Asian pear ( Pyrus pyrifolia ) from Italy and Korea were virulent on leaves and young fruits of the susceptible Asian pear cv. Nijisseiki. Their conidial morphology was typical of A. gaisen (= A. kikuchiana ). Only isolates of A. mali from USA were virulent on susceptible American apple cvs Indo and Red Gold. No virulence was demonstrated in any isolate/host combination among isolates from stem infections of Asian and European pear ( Pyrus communis ), leaf spots of European apple, and ripe fruit rots of Chinese pear ( Pyrus ussuriensis ), European pear and apple. These non-virulent isolates could be readily distinguished from A. gaisen and A. mali by their pattern of branching of conidial chains, the branching associated with A. alternata sensu stricto being most common among non-virulent isolates. This limited survey implies that A. gaisen is only virulent to Asian pear and the toxigenic form of A. mali to certain American apple cultivars; also that A. gaisen is not established outside eastern Asia or the toxigenic form of A. mali outside eastern Asia and parts of USA. 相似文献