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Francesco Spinelli - One of the best experts on this subject based on the ideXlab platform.
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elicitors of the salicylic acid pathway reduce incidence of Bacterial Canker of kiwifruit caused by pseudomonas syringae pv actinidae
Annals of Applied Biology, 2014Co-Authors: Antonio Cellini, Irene Donati, Giampaolo Buriani, Guglielmo Costa, J L Vanneste, D A Cornish, Luca Fiorentini, Barbara Novak, Francesco SpinelliAbstract:Some strains of Pseudomonas syringae pv. actinidiae (Psa), the causal agent of Bacterial Canker of kiwifruit, produce plant hormones and toxins which alter the plant hormonal balance and result in the suppression of the salicylic acid (SA)-dependent plant defences. To determine whether Psa could be affected by stimulation of the SA pathway, Actinidia deliciosa and A. chinensis were treated with compounds which interfere with this pathway, then inoculated with Psa. On A. deliciosa, compounds which stimulate the SA pathway [SA, or its synthetic analogue, acibenzolar-S-methyl (ASM)] or close stomata (ABA) resulted in disease reduction, while methyl-jasmonate (MJA) or ethylene increased disease development. On A. chinensis, similar results were obtained except that SA and MJA did not affect disease development. Reduction in disease incidence and severity on A. deliciosa using ASM was correlated with a superoxide burst, the formation of necrotic spots and callose deposition, while on A. chinensis no superoxide burst or callose deposition was detected. Genes involved in plant–pathogen interactions were induced after treatment with ASM in A. deliciosa and, to a lesser extent, in A. chinensis. Those differences in gene expression and physiological responses after treatment with ASM are consistent with the different susceptibility to Psa observed between A. chinensis and A. deliciosa.
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new insights on the Bacterial Canker of kiwifruit pseudomonas syringae pv actinidiae
Journal of Berry Research, 2014Co-Authors: Irene Donati, Giampaolo Buriani, Antonio Cellini, Sofia Mauri, Guglielmo Costa, Francesco SpinelliAbstract:Since 2008, Pseudomonas syringae pv. actinidiae, the causal agent of Bacterial Canker of kiwifruit has become the main pathogen of yellow and green fleshed kiwifruit. All major kiwifruit producing countries in the world have been affected by this Bacterial pathogen, leading to substantial economic losses. This review presents the current knowledge on various aspects about the origin, epidemiology, detection and control strategies of Pseudomonas syringae pv. actinidiae.
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using fundamental knowledge of induced resistance to develop control strategies for Bacterial Canker of kiwifruit caused by pseudomonas syringae pv actinidiae
Frontiers in Plant Science, 2013Co-Authors: T Reglinski, Francesco Spinelli, J L Vanneste, K V Wurms, Elaine M Gould, Erik H A RikkerinkAbstract:Pseudomonas syringae pv. actinidiae (Psa) which causes Bacterial Canker of kiwifruit (Actinidia deliciosa and A. chinensis) was first isolated in Japan in 1984 (Takikawa et al., 1989), and soon after in Korea (Koh et al., 1994) and Italy (Scortichini, 1994). The economic impact on the global production of kiwifruit of those early occurrences was relatively limited (Vanneste et al., 2011). However, the latest outbreak of Psa which started in Italy in 2008 and rapidly spread throughout most of the kiwifruit growing regions of the world, represents a major threat to the global kiwifruit industry (Vanneste, 2012). The pathovar actinidiae is not a genetically homogeneous pathovar; strains can be grouped in four biovars based on their molecular, microbiological and pathogenic characteristics (Vanneste et al., 2013) which is consistent with MLST and whole genome sequence analysis (Ferrante and Scortichini, 2010; Mazzaglia et al., 2011; Chapman et al., 2012). The recent outbreak of Bacterial Canker on kiwifruit in Europe and New Zealand is caused by the same biovar of Psa (biovar 3) (Chapman et al., 2012; Vanneste et al., 2013). During the 2 years that the pathogen has been present in New Zealand, over 60% of the area planted in kiwifruit has been affected (Kiwifruit Vine Health, 2012). This rapid spread may be attributable to the virulence of biovar 3 and to the scarcity of products available for control of plant pathogenic bacteria in general, and Psa in particular. Many products used for control of plant pathogenic bacteria contain antibiotics (mostly streptomycin) or heavy metals (mostly copper). Both types of products do have limitations because of phytotoxicity or because they are not authorized in some countries (e.g., antibiotics in Europe). This has led to a large screening programme in New Zealand for the identification of potentially effective products to control Psa. The products tested included a number of commercially available potential elicitors of host resistance. One of the most effective elicitors in glasshouse trials on A. chinensis and A. deliciosa was acibenzolar-S-methyl [ASM], sold under the names of Bion® or Actigard® (Syngenta).
Adrian Alberto Vojnov - One of the best experts on this subject based on the ideXlab platform.
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rapid and sensitive detection of citrus Bacterial Canker by loop mediated isothermal amplification combined with simple visual evaluation methods
BMC Microbiology, 2010Co-Authors: Luciano A Rigano, Maria Rosa Marano, Atilio Pedro Castagnaro, Alexandre Morais Do Amaral, Adrian Alberto VojnovAbstract:Citrus Bacterial Canker (CBC) is a major, highly contagious disease of citrus plants present in many countries in Asia, Africa and America, but not in the Mediterranean area. There are three types of Citrus Bacterial Canker, named A, B, and C that have different genotypes and posses variation in host range within citrus species. The causative agent for type A CBC is Xanthomonas citri subsp. citri, while Xanthomonas fuscans subsp. aurantifolii, strain B causes type B CBC and Xanthomonas fuscans subsp. aurantifolii strain C causes CBC type C. The early and accurate identification of those bacteria is essential for the protection of the citrus industry. Detection methods based on Bacterial isolation, antibodies or polymerase chain reaction (PCR) have been developed previously; however, these approaches may be time consuming, laborious and, in the case of PCR, it requires expensive laboratory equipment. Loop-mediated isothermal amplification (LAMP), which is a novel isothermal DNA amplification technique, is sensitive, specific, fast and requires no specialized laboratory equipment. A loop-mediated isothermal amplification assay for the diagnosis of Citrus Bacterial Canker (CBC-LAMP) was developed and evaluated. DNA samples were obtained from infected plants or cultured bacteria. A typical ladder-like pattern on gel electrophoresis was observed in all positive samples in contrast to the negative controls. In addition, amplification products were detected by visual inspection using SYBRGreen and using a lateral flow dipstick, eliminating the need for gel electrophoresis. The sensitivity and specificity of the assay were evaluated in different conditions and using several sample sources which included purified DNA, bacterium culture and infected plant tissue. The sensitivity of the CBC-LAMP was 10 fg of pure Xcc DNA, 5 CFU in culture samples and 18 CFU in samples of infected plant tissue. No cross reaction was observed with DNA of other phytopathogenic bacteria. The assay was capable of detecting CBC-causing strains from several geographical origins and pathotypes. The CBC-LAMP technique is a simple, fast, sensitive and specific method for the diagnosis of Citrus Bacterial Canker. This method can be useful in the phytosanitary programs of the citrus industry worldwide.
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rapid and sensitive detection of citrus Bacterial Canker by loop mediated isothermal amplification combined with simple visual evaluation methods
BMC Microbiology, 2010Co-Authors: Luciano A Rigano, Maria Rosa Marano, Atilio Pedro Castagnaro, Alexandre Morais Do Amaral, Adrian Alberto VojnovAbstract:Background Citrus Bacterial Canker (CBC) is a major, highly contagious disease of citrus plants present in many countries in Asia, Africa and America, but not in the Mediterranean area. There are three types of Citrus Bacterial Canker, named A, B, and C that have different genotypes and posses variation in host range within citrus species. The causative agent for type A CBC is Xanthomonas citri subsp. citri, while Xanthomonas fuscans subsp. aurantifolii, strain B causes type B CBC and Xanthomonas fuscans subsp. aurantifolii strain C causes CBC type C. The early and accurate identification of those bacteria is essential for the protection of the citrus industry. Detection methods based on Bacterial isolation, antibodies or polymerase chain reaction (PCR) have been developed previously; however, these approaches may be time consuming, laborious and, in the case of PCR, it requires expensive laboratory equipment. Loop-mediated isothermal amplification (LAMP), which is a novel isothermal DNA amplification technique, is sensitive, specific, fast and requires no specialized laboratory equipment.
G M Balestra - One of the best experts on this subject based on the ideXlab platform.
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Bacillus sp. strains, an effective tool to face out the Bacterial Canker of kiwifruit
2019Co-Authors: Biondi E., A Mazzaglia, L. Gallipoli, S. Perez, A. Bertaccini, G M BalestraAbstract:In the last decade, Bacterial Canker of kiwifruit, caused by Pseudomonas syringae pv. actinidiae (Psa), provoked heavy economical losses since its pandemic spread in 2008. The control of disease is achieved through integrated methods, by combining appropriate cultural practices and chemical treatments as cupric salts/antibiotics, and biocontrol agents (BCA). In this study, two strains QST713 andD747 of Bacillus sp., active principle of commercial biofungicides, were investigated for their ability to reduce the in vitro Psa growth. Both Bacterial strains were assayed in planta for their capacity in directly reducing the severity of Bacterial Canker on green- and yellow-fleshed kiwifruit plants under greenhouse and open field conditions. Moreover, D747 strain was studied for its ability to induce resistance against Psa in yellow-fleshed kiwifruit plants after its application at the roots by irrigation with a suspension of the antagonist. In in vitro experiments the strains QST713 and D747 resulted similar in reducing Psa growth. Under greenhouse conditions, when applied on kiwifruit plants 48 h before the Psa inoculation, only the strain D747 resulted able to significantly reduce the disease severity, and in open field it prevented the natural Psa infection and lowered the disease severity. D747 was also able to reduce the disease severity by inducing plant resistance after its application at the roots. These are the first results which concern the ability of a BCA in directly reducing the pathogen growth and its disease severity, as well as its indirect capacity to induce resistance in Actinidia spp. plants towards Psa
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pseudomonas syringae pv actinidiae psa isolates from recent Bacterial Canker of kiwifruit outbreaks belong to the same genetic lineage
PLOS ONE, 2012Co-Authors: A Mazzaglia, David J Studholme, M C Taratufolo, Rongman Cai, Nalvo F Almeida, Tokia Goodman, David S Guttman, Boris A Vinatzer, G M BalestraAbstract:Intercontinental spread of emerging plant diseases is one of the most serious threats to world agriculture. One emerging disease is Bacterial Canker of kiwi fruit (Actinidia deliciosa and A. chinensis) caused by Pseudomonas syringae pv. actinidiae (PSA). The disease first occurred in China and Japan in the 1980s and in Korea and Italy in the 1990s. A more severe form of the disease broke out in Italy in 2008 and in additional countries in 2010 and 2011 threatening the viability of the global kiwi fruit industry. To start investigating the source and routes of international transmission of PSA, genomes of strains from China (the country of origin of the genus Actinidia), Japan, Korea, Italy and Portugal have been sequenced. Strains from China, Italy, and Portugal have been found to belong to the same clonal lineage with only 6 single nucleotide polymorphisms (SNPs) in 3,453,192 bp and one genomic island distinguishing the Chinese strains from the European strains. Not more than two SNPs distinguish each of the Italian and Portuguese strains from each other. The Japanese and Korean strains belong to a separate genetic lineage as previously reported. Analysis of additional European isolates and of New Zealand isolates exploiting genome-derived markers showed that these strains belong to the same lineage as the Italian and Chinese strains. Interestingly, the analyzed New Zealand strains are identical to European strains at the tested SNP loci but test positive for the genomic island present in the sequenced Chinese strains and negative for the genomic island present in the European strains. Results are interpreted in regard to the possible direction of movement of the pathogen between countries and suggest a possible Chinese origin of the European and New Zealand outbreaks.
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first report of Bacterial Canker of actinidia deliciosa caused by pseudomonas syringae pv actinidiae in portugal
New Disease Reports, 2010Co-Authors: G M Balestra, M Renzi, A MazzagliaAbstract:Bacterial Canker caused by Pseudomonas syringae pv. actinidiae is one of the most harmful diseases affecting kiwifruit plants. It was first isolated and identified in Japan on kiwifruit plants(Actinidia deliciosa) and was subsequently recorded in the most important world kiwifruit production areas, China, Korea and Italy, on the main species (A. deliciosa and A. chinensis) and cultivars of kiwifruit. A new serious outbreak of the disease was observed during the spring (March) 2010 on two-year-old plants of A. deliciosa cv. Summer, in kiwifruit orchards in Entre Douro and Mino provinces in Portugal. The symptoms were characterised by dark brown spots surrounded by yellow haloes on leaves, and Cankers with copious reddish exudate production on twigs and stem (Fig. 1). Disease incidence could be as high as 30%. Bacterial colonies were isolated from infected tissues on nutrient agar containing 5% sucrose. Six isolates obtained were Gram-negative, and negative for oxidase, potato soft rot, arginine dehydrolase, presence of tyrosinase and urease, nitrate and fluorescent pigment production. Moreover, they were positive for levan production, presence of catalase and for tobacco hypersensitivity (Lelliott & Stead, 1988). Pathogenicity was confirmed by artificial inoculation of ten healthy two-year-old A. deliciosa plants, cv. Hayward, with Bacterial suspensions (10 7 cfu/ml). The symptoms were observed within five and 14 days after inoculation on leaves and twigs, respectively. No symptoms were observed on control plants, and bacteria with morphological, biochemical and molecular characteristics identical to the original isolate were reisolated from tissue showing symptoms. Four isolates (PSA346, PSA349, PSA352, PSA356) were chosen for molecular identification and analysed in comparison with P.s. pv actinidiae reference strains (CFBP 7285, CFBP 7286, CFBP 7287). Identity as P.s. pv. actinidiae was confirmed by PCR amplification with two pairs of pathovar-specific primers (Koh & Nou, 2002; Rees-George et al., 2010). This is the first report on the occurrence of this Bacterial pathogen on A. deliciosa in Portugal.
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first report of Bacterial Canker of actinidia deliciosa caused by pseudomonas syringae pv actinidiae in portugal
New Disease Reports, 2010Co-Authors: G M Balestra, M Renzi, A MazzagliaAbstract:Bacterial Canker caused by Pseudomonas syringae pv. actinidiae is one of the most harmful diseases affecting kiwifruit plants. It was first isolated and identified in Japan on kiwifruit plants(Actinidia deliciosa) and was subsequently recorded in the most important world kiwifruit production areas, China, Korea and Italy, on the main species (A. deliciosa and A. chinensis) and cultivars of kiwifruit. A new serious outbreak of the disease was observed during the spring (March) 2010 on two-year-old plants of A. deliciosa cv. Summer, in kiwifruit orchards in Entre Douro and Mino provinces in Portugal. The symptoms were characterised by dark brown spots surrounded by yellow haloes on leaves, and Cankers with copious reddish exudate production on twigs and stem (Fig. 1). Disease incidence could be as high as 30%. Bacterial colonies were isolated from infected tissues on nutrient agar containing 5% sucrose. Six isolates obtained were Gram-negative, and negative for oxidase, potato soft rot, arginine dehydrolase, presence of tyrosinase and urease, nitrate and fluorescent pigment production. Moreover, they were positive for levan production, presence of catalase and for tobacco hypersensitivity (Lelliott & Stead, 1988). Pathogenicity was confirmed by artificial inoculation of ten healthy two-year-old A. deliciosa plants, cv. Hayward, with Bacterial suspensions (10 7 cfu/ml). The symptoms were observed within five and 14 days after inoculation on leaves and twigs, respectively. No symptoms were observed on control plants, and bacteria with morphological, biochemical and molecular characteristics identical to the original isolate were reisolated from tissue showing symptoms. Four isolates (PSA346, PSA349, PSA352, PSA356) were chosen for molecular identification and analysed in comparison with P.s. pv actinidiae reference strains (CFBP 7285, CFBP 7286, CFBP 7287). Identity as P.s. pv. actinidiae was confirmed by PCR amplification with two pairs of pathovar-specific primers (Koh & Nou, 2002; Rees-George et al., 2010). This is the first report on the occurrence of this Bacterial pathogen on A. deliciosa in Portugal.
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current status of Bacterial Canker spread on kiwifruit in italy
Australasian Plant Disease Notes, 2009Co-Authors: G M Balestra, A Mazzaglia, A Quattrucci, M Renzi, Antonio RossettiAbstract:A survey of kiwifruit orchards in central and northern Italy during 2007–2008 consistently detected serious damage caused by Bacterial Canker. The causal agent, Pseudomonas syringae pv. actinidiae, was repeatedly isolated from diseased plants, mainly Actinidia chinensis Pl. cultivars. Pseudomonas syringae pv. actinidiae was identified by morphological, physiological, and biochemical characteristics as well as molecular analyses. Disease severity, varietal susceptibility, trade implications and control strategies are discussed.
S Loreti - One of the best experts on this subject based on the ideXlab platform.
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in vitro antimicrobial activity of plant extracts against pseudomonas syringae pv actinidiae causal agent of Bacterial Canker in kiwifruit
Plant Biosystems, 2020Co-Authors: Giovanna Simonetti, Nicoletta Pucci, Elisa Brasili, Alessio Valletta, Iris Sammarco, Eleonora Carnevale, Gabriella Pasqua, S LoretiAbstract:Pseudomonas syringae pv. actinidiae (Psa), the causal agent of Bacterial Canker of kiwifruit, is considered the main pathogen of yellow-, green- and red-fleshed kiwifruit. All major kiwifruit produ...
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real time and qualitative pcr for detecting pseudomonas syringae pv actinidiae isolates causing recent outbreaks of kiwifruit Bacterial Canker
Plant Pathology, 2014Co-Authors: A Gallelli, S Talocci, M Pilotti, S LoretiAbstract:Since 2008, Pseudomonas syringae pv. actinidiae virulent strains (Psa-V) have quickly spread across the main areas of kiwifruit (Actinidia deliciosa and A. chinensis) cultivation causing sudden and re-emerging outbreaks of Bacterial Canker to both species. The disease caused by Psa-V strains is considered worldwide as pandemic. Recently, P. syringae strains (ex Psa-LV, now called PsD) phylogenetically related to Psa-V have been isolated from kiwifruit, but cause only minor damage (i.e. leaf spot) to the host. The different biological significance of these Bacterial populations affecting kiwifruit highlights the importance of having a diagnostic method able to detect Psa-V, which is currently solely responsible for the severe damage to the kiwifruit industry. In order to improve the specific molecular detection of Psa-V, a real-time PCR assay has been developed based on EvaGreen chemistry, together with a novel qualitative PCR (PCR-C). Both methods are based on specific primer sets for the hrpW gene of Psa. The real-time PCR and PCR-C were highly specific, detecting down to 50 and 200 fg, respectively, and were applied to a range of organs/tissues of kiwifruit with and without symptoms. These methods are important tools for both sanitary and certification programmes, and will help to avoid the spread of Psa-V and to check possible inoculum sources. In addition to being used as routine tests, they will also enable the study of the biology of Psa-V and the disease that it causes, whilst avoiding the detection of other populations of related P. syringae present in kiwifruit.
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detection of pseudomonas syringae pv actinidiae causal agent of Bacterial Canker of kiwifruit from symptomless fruits and twigs and from pollen
Phytopathologia Mediterranea, 2012Co-Authors: A Gallelli, S Talocci, Alessia Laurora, S LoretiAbstract:Pseudomonas syringae pv. actinidiae (Psa), the causal agent of Bacterial Canker of kiwifruit, was monitored in symptomless fruits, twigs and pollen of the host using Bacterial isolation and DNA-extraction followed by two PCR-assays (direct-PCRs). A procedure for Psa detection from symptomless twigs was established. Out of 16 symptomless twigs samples, Psa was detected in 12 samples by isolation and 13 samples by direct-PCR. Thirteen pollen samples were treated using two different procedures; Psa was detected in eight samples by isolation and ten samples by direct-PCR. By washing 108 samples of fruits, Psa was detected by isolation in only two samples, collected from severely affected orchards. However, one of these samples contained wilted fruits, whereas for the other, only one colony was isolate. From 60 bulk-samples of fruits, endophytic Psa was detected in six samples by isolation and ten samples by direct-PCRs. A Psa-positive bulk-sample of fruits was analyzed separately as individual fruits: there was a faint signal in five or seven fruits out of 50 depending on the PCR assay used. Isolation was negative for these samples. Presence of the pathogen on bulk-fruit samples could be due to low amounts of inoculum distributed over many fruits: as a consequence, there is a negligible risk of introducing the pathogen into countries free of Bacterial Canker. This integrated approach (isolation plus PCR) is proposed as a tool for the analysis of symptomless kiwifruit material for the presence of Psa.
Donald L. Smith - One of the best experts on this subject based on the ideXlab platform.
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biocontrol rhizobacterium pseudomonas sp 23s induces systemic resistance in tomato solanum lycopersicum l against Bacterial Canker clavibacter michiganensis subsp michiganensis
Frontiers in Microbiology, 2018Co-Authors: Yoko Takishita, Jean-benoit Charron, Donald L. SmithAbstract:Tomato Bacterial Canker disease, caused by Clavibacter michiganensis subsp. michiganensis (Cmm) is a destructive disease and has been a serious concern for tomato industries worldwide. Previously, a rhizosphere isolated strain of Pseudomonas sp. 23S showed antagonistic activity toward Cmm in vitro. This Pseudomonas sp. 23S was characterized to explore the potential of this bacterium for its use in agriculture. Pseudomonas sp. 23S possesses ability to solubilize inorganic phosphorus, and to produce siderophores, indole acetic acid, and hydrogen cyanide. The strain also showed antagonistic activity against Pseudomonas syringae pv. tomato DC 3000. A plant assay indicated that Pseudomonas sp. 23S could promote growth of tomato seedlings. The potential of treating tomato plants with Pseudomonas sp. 23S to reduce the severity of tomato Bacterial Canker by inducing systemic resistance (ISR) was investigated using well characterized marker genes such as PR1a [salicylic acid (SA)], PI2 [jasmonic acid (JA)], and ACO [ethylene (ET)]. Two-week-old tomato plants were treated with Pseudomonas sp. 23S by soil drench, and Cmm was inoculated into the stem by needle injection on 3, 5, or 7 days post drench. The results indicated that plants treated with Pseudomonas sp. 23S, 5 days prior to Cmm inoculation significantly delayed the progression of the disease. These plants, after 3 weeks from the date of Cmm inoculation, had significantly higher dry shoot and root weight, higher levels of carbon, nitrogen, phosphorus, and potassium in the leaf tissue, and the number of Cmm population in the stem was significantly lower for the plants treated with Pseudomonas sp. 23S. From the real-time quantitative PCR (qRT-PCR) analysis, the treatment with Pseudomonas sp. 23S alone was found to trigger a significant increase in the level of PR1a transcripts in tomato plants. When the plants were treated with Pseudomonas sp. 23S and inoculated with Cmm, the level of PR1a and ACO transcripts were increased, and this response was faster and greater as compared to plants inoculated with Cmm but not treated with Pseudomonas sp. 23S. Overall, the results suggested the involvement of SA signaling pathways for ISR induced by Pseudomonas sp. 23S.
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Image_4_Biocontrol Rhizobacterium Pseudomonas sp. 23S Induces Systemic Resistance in Tomato (Solanum lycopersicum L.) Against Bacterial Canker Clavibacter michiganensis subsp. michiganensis.JPEG
2018Co-Authors: Yoko Takishita, Jean-benoit Charron, Donald L. SmithAbstract:Tomato Bacterial Canker disease, caused by Clavibacter michiganensis subsp. michiganensis (Cmm) is a destructive disease and has been a serious concern for tomato industries worldwide. Previously, a rhizosphere isolated strain of Pseudomonas sp. 23S showed antagonistic activity toward Cmm in vitro. This Pseudomonas sp. 23S was characterized to explore the potential of this bacterium for its use in agriculture. Pseudomonas sp. 23S possesses ability to solubilize inorganic phosphorus, and to produce siderophores, indole acetic acid, and hydrogen cyanide. The strain also showed antagonistic activity against Pseudomonas syringae pv. tomato DC 3000. A plant assay indicated that Pseudomonas sp. 23S could promote growth of tomato seedlings. The potential of treating tomato plants with Pseudomonas sp. 23S to reduce the severity of tomato Bacterial Canker by inducing systemic resistance (ISR) was investigated using well characterized marker genes such as PR1a [salicylic acid (SA)], PI2 [jasmonic acid (JA)], and ACO [ethylene (ET)]. Two-week-old tomato plants were treated with Pseudomonas sp. 23S by soil drench, and Cmm was inoculated into the stem by needle injection on 3, 5, or 7 days post drench. The results indicated that plants treated with Pseudomonas sp. 23S, 5 days prior to Cmm inoculation significantly delayed the progression of the disease. These plants, after 3 weeks from the date of Cmm inoculation, had significantly higher dry shoot and root weight, higher levels of carbon, nitrogen, phosphorus, and potassium in the leaf tissue, and the number of Cmm population in the stem was significantly lower for the plants treated with Pseudomonas sp. 23S. From the real-time quantitative PCR (qRT-PCR) analysis, the treatment with Pseudomonas sp. 23S alone was found to trigger a significant increase in the level of PR1a transcripts in tomato plants. When the plants were treated with Pseudomonas sp. 23S and inoculated with Cmm, the level of PR1a and ACO transcripts were increased, and this response was faster and greater as compared to plants inoculated with Cmm but not treated with Pseudomonas sp. 23S. Overall, the results suggested the involvement of SA signaling pathways for ISR induced by Pseudomonas sp. 23S.