289 GENOTYPIC DIFFERENCES IN THE INDUCTION OF DISEASE RESISTANCE WITHIN CUCUMIS SATIVUS

Systemic resistance to necrotic lesion forming pathogens can be induced in certain plant species by inoculating a young leaf with a limited amount of pathogen or by treating with specific non-pesticidal chemical compounds. A physiological change correlated with the induced resistance response is an increase in the activity of acidic apoplastic peroxidases. When seedlings of 17 inbred lines of fresh market and pickling cucumbers were foliar treated with 20 ppm 2,6-dichloroisonicotinic acid (Ciba Geigy 41396) and subsequently inoculated with either Pseudomonas syringae pv. lachrymans or Colletotrichum lagenarium, significant differences were observed in the number of lesions that developed. CG 41396 treatment also gave rise to 4-fold (Producer and Early Russian), 3-fold (Poinsett and Straight 8) and 2-fold (Delcrow, WI 2757, TMG-1, TG 72) increases in peroxidase activity within inbred lines. Distinct changes in acid peroxidase electrophoretic isozyme banding patterns were observed within certain inbred lines after treatment with CG 41396. These results indicate that genetic variability exists within Cucumis sativus with respect to plant response to physiological disease resistance inducing treatments.

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Pseudomonas syringae Effector AvrPphB Suppresses AvrB-Induced Activation of RPM1 but Not AvrRpm1-Induced Activation

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-08-14-0248-r ◽

2015 ◽

Vol 28 (6) ◽

pp. 727-735 ◽

Cited By ~ 24

Author(s):

Andrew R. Russell ◽

Tom Ashfield ◽

Roger W. Innes

Keyword(s):

Disease Resistance ◽

Protein Kinase ◽

Molecular Mechanism ◽

Pseudomonas Syringae ◽

Hypersensitive Response ◽

Hypersensitive Resistance ◽

Nicotiana Glutinosa ◽

Resistance Response ◽

Interacting Protein ◽

Soybean Plants

The Pseudomonas syringae effector AvrB triggers a hypersensitive resistance response in Arabidopsis and soybean plants expressing the disease resistance (R) proteins RPM1 and Rpg1b, respectively. In Arabidopsis, AvrB induces RPM1-interacting protein kinase (RIPK) to phosphorylate a disease regulator known as RIN4, which subsequently activates RPM1-mediated defenses. Here, we show that AvrPphB can suppress activation of RPM1 by AvrB and this suppression is correlated with the cleavage of RIPK by AvrPphB. Significantly, AvrPphB does not suppress activation of RPM1 by AvrRpm1, suggesting that RIPK is not required for AvrRpm1-induced modification of RIN4. This observation indicates that AvrB and AvrRpm1 recognition is mediated by different mechanisms in Arabidopsis, despite their recognition being determined by a single R protein. Moreover, AvrB recognition but not AvrRpm1 recognition is suppressed by AvrPphB in soybean, suggesting that AvrB recognition requires a similar molecular mechanism in soybean and Arabidopsis. In support of this, we found that phosphodeficient mutations in the soybean GmRIN4a and GmRIN4b proteins are sufficient to block Rpg1b-mediated hypersensitive response in transient assays in Nicotiana glutinosa. Taken together, our results indicate that AvrB and AvrPphB target a conserved defense signaling pathway in Arabidopsis and soybean that includes RIPK and RIN4.

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A 2′-O-Methyltransferase Responsible for Transfer RNA Anticodon Modification Is Pivotal for Resistance to Pseudomonas syringae DC3000 in Arabidopsis

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-06-18-0148-r ◽

2018 ◽

Vol 31 (12) ◽

pp. 1323-1336 ◽

Cited By ~ 2

Author(s):

Vicente Ramírez ◽

Beatriz González ◽

Ana López ◽

Maria Jose Castelló ◽

Maria José Gil ◽

...

Keyword(s):

Disease Resistance ◽

Pseudomonas Syringae ◽

Bacterial Pathogen ◽

Transfer Rna ◽

Resistance Response ◽

Chemical Structures ◽

Trna Modifications ◽

Trna Species ◽

Living Organisms ◽

And Function

Transfer RNA (tRNA) is the most highly modified class of RNA species in all living organisms. Recent discoveries have revealed unprecedented complexity in the tRNA chemical structures, modification patterns, regulation, and function, suggesting that each modified nucleoside in tRNA may have its own specific function. However, in plants, our knowledge of the role of individual tRNA modifications and how they are regulated is very limited. In a genetic screen designed to identify factors regulating disease resistance in Arabidopsis, we identified SUPPRESSOR OF CSB3 9 (SCS9). Our results reveal SCS9 encodes a tRNA methyltransferase that mediates the 2′-O-ribose methylation of selected tRNA species in the anticodon loop. These SCS9-mediated tRNA modifications enhance susceptibility during infection with the virulent bacterial pathogen Pseudomonas syringae DC3000. Lack of such tRNA modification, as observed in scs9 mutants, specifically dampens plant resistance against DC3000 without compromising the activation of the salicylic acid signaling pathway or the resistance to other biotrophic pathogens. Our results support a model that gives importance to the control of certain tRNA modifications for mounting an effective disease resistance in Arabidopsis toward DC3000 and, therefore, expands the repertoire of molecular components essential for an efficient disease resistance response.

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Transcript and metabolite analysis of the Trichoderma-induced systemic resistance response to Pseudomonas syringae in Arabidopsis thaliana

Microbiology ◽

10.1099/mic.0.052621-0 ◽

2012 ◽

Vol 158 (1) ◽

pp. 139-146 ◽

Cited By ~ 102

Author(s):

Yariv Brotman ◽

Jan Lisec ◽

Michaël Méret ◽

Ilan Chet ◽

Lothar Willmitzer ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Pseudomonas Syringae ◽

Induced Systemic Resistance ◽

Systemic Resistance ◽

Metabolite Analysis ◽

Resistance Response

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Independence of the mj Nematode Resistance Gene from 17 Gene Loci in Cucumber

HortScience ◽

10.21273/hortsci.33.6.1050 ◽

1998 ◽

Vol 33 (6) ◽

pp. 1050-1052 ◽

Cited By ~ 3

Author(s):

S. Alan Walters ◽

Todd C. Wehner

Keyword(s):

Disease Resistance ◽

Resistance Gene ◽

Cucumis Sativus ◽

Field Tests ◽

Meloidogyne Javanica ◽

Nematode Resistance ◽

Inbred Lines ◽

Nematode Resistance Gene ◽

Important Disease ◽

Resistance Traits

Root knot caused by Meloidogyne spp. is an important disease of cucumber. Resistance to M. javanica in cucumber (Cucumis sativus L.) is conferred by the newly discovered mj gene. The objective of this research was to determine whether mj was linked to other genes controlling morphological or disease resistance traits in cucumber. Four inbred lines homozygous for mj (LJ 90430, `Manteo', NCG-198, and NCG-199) were crossed with inbreds (`Coolgreen', M 21, NCG-101, WI 2757, and `Wisconsin SMR 18') to form six families: NCG-101 × LJ 90430, WI 2757 × LJ 90430, NCG-199 × `Wis. SMR 18', NCG-198 × M 21, `Manteo' × M 21, and NCG-198 × `Coolgreen'. F2 progeny were evaluated in all families, and BC1 progeny were evaluated only in the NCG-199 × `Wis. SMR 18' family. Meloidogyne javanica resistance and the 17 other traits controlled by simple genes were evaluated in greenhouse or field tests. None of the 17 genes were linked with mj. Therefore, cucumber breeders interested in nematode resistance should be able to incorporate the trait into lines without having to break linkages with the 17 genes used in this study.

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Bacterial Blight on Arugula, a New Disease Caused by Pseudomonas syringae pv. Alisalensis in California

Plant Disease ◽

10.1094/pdis.2004.88.12.1384a ◽

2004 ◽

Vol 88 (12) ◽

pp. 1384-1384 ◽

Cited By ~ 11

Author(s):

C. T. Bull ◽

P. Goldman ◽

S. T. Koike

Keyword(s):

Pseudomonas Syringae ◽

Bacterial Blight ◽

Acid Methyl Ester ◽

Hypersensitive Reaction ◽

Nutrient Broth ◽

Leaf Spot Disease ◽

Diagnostic Feature ◽

Fluorescent Pseudomonad ◽

Fresh Market ◽

Banding Patterns

Beginning in 1995, a leaf spot disease has occasionally developed on the leafy crucifer arugula (Eruca vesicaria subsp. sativa) that is grown in coastal California as a fresh market commodity used mostly in bagged salad mixes. Initially, symptoms consist of small (<2 mm in diameter), angular, water-soaked spots that are visible from both sides of the leaf. The spots later enlarge, remain angular in shape, and turn brown to tan. A purple margin sometimes occurs around the spots. An important diagnostic feature is that this disease closely resembles downy mildew infections that have not produced sporangia (3). A blue-green fluorescent pseudomonad was consistently isolated from both types of lesions on King's medium B. Strains were levan positive, oxidase negative, and arginine dihydrolase negative. Strains did not rot potato slices but induced a hypersensitive reaction on tobacco (Nicotiana tabacum L. cv. Turk). These data indicated that the bacteria belonged to Lelliot's LOPAT group 1 (4). This was confirmed with data from fatty acid methyl ester analysis (MIS-TSBA version 4.10; MIDI, Inc., Newark, DE), which indicated that the strains were highly similar (similarity > = 0.758) to Pseudomonas syringae. Amplification of repetitive bacterial sequence-based polymerase chain reaction (rep-PCR) was used to determine the relationship between the P. syringae strains isolated from arugula and two common crucifer pathogens, P. syringae pv. maculicola and P. syringae pv. alisalensis (1). Using the BOXA1R primer, banding patterns for the arugula strains and the P. syringae pv. alisalensis pathotype were similar, differing by only one band. In contrast, the banding patterns of the arugula strains differed significantly from those of P. syringae pv. maculicola. Additionally, the arugula isolates were sensitive to a bacteriophage originally isolated for its ability to lyse P. syringae pv. alisalensis (1). Previously, the pathogen from arugula was reported to be P. syringae pv. maculicola (2). It is the intent of this disease note to clarify this identification. We completed Koch's postulates by confirming pathogenicity on arugula (cv. Rocket Salad). The strains were grown as nutrient broth shake cultures for 48 h at 24°C, adjusted to 108 CFU/ml, and misted onto 2- to 3-week old plants. Control plants were misted with sterile nutrient broth. After 4 to 5 days in a greenhouse (24 to 26°C), large, angular leaf lesions developed on all inoculated arugula plants. Strains were reisolated from symptomatic tissue and identified as P. syringae pv. alisalensis. Control plants remained symptomless. Similar methods confirmed that the host range of the arugula isolates were identical to that of P. syringae pv. alisalensis. The arugula and P. syringae pv. alisalensis isolates caused disease on broccoli (Brassica oleracea var. botrytis cvs. Patriot and Titleist), broccoli raab (B. rapa subsp. rapa cv. Sorento), and oats (Avena sativa cv. Montezuma), while P. syringae pv. maculicola caused disease on broccoli only. Pathogenicity tests were conducted two times with identical results. This confirms that the bacterial blight that has been occurring on commercial plantings of arugula is caused by P. syringae pv. alisalensis. References: (1) N. A. Cintas et al.Plant Dis. 86:992, 2002. (2) S. T. Koike et al. Plant Dis. 80:464, 1996. (3) S. T. Koike. Plant Dis. 82:1063, 1998. (4) R. A. Lelliott, J. Appl. Bacteriol. 29:470, 1966.

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Identification of a Locus in Arabidopsis Controlling Both the Expression of Rhizobacteria-Mediated Induced Systemic Resistance (ISR) and Basal Resistance Against Pseudomonas syringae pv. tomato

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi.1999.12.10.911 ◽

1999 ◽

Vol 12 (10) ◽

pp. 911-918 ◽

Cited By ~ 65

Author(s):

Jurriaan Ton ◽

Corné M. J. Pieterse ◽

Leendert C. Van Loon

Keyword(s):

Pseudomonas Syringae ◽

Systemic Acquired Resistance ◽

Induced Systemic Resistance ◽

Acquired Resistance ◽

Dominant Gene ◽

Systemic Resistance ◽

Control Activity ◽

Resistance Response ◽

Basal Resistance ◽

High Level

Selected nonpathogenic rhizobacteria with biological disease control activity are able to elicit an induced systemic resistance (ISR) response that is phenotypically similar to pathogen-induced systemic acquired resistance (SAR). Ten ecotypes of Arabidopsis thaliana were screened for their potential to express rhizobacteria-mediated ISR and pathogen-induced SAR against the leaf pathogen Pseudomonas syringae pv. tomato DC3000 (Pst). All ecotypes expressed SAR. However, of the 10 ecotypes tested, ecotypes RLD and Wassilewskija (Ws) did not develop ISR after treatment of the roots with nonpathogenic Pseudomonas fluorescens WCS417r bacteria. This nonresponsive phenotype was associated with relatively high susceptibility to Pst infection. The F1 progeny of crosses between the non-responsive ecotypes RLD and Ws on the one hand, and the responsive ecotypes Columbia (Col) and Landsberg erecta (Ler) on the other hand, were fully capable of expressing ISR and exhibited a relatively high level of basal resistance, similar to that of their WCS417r-responsive parent. This indicates that the potential to express ISR and the relatively high level of basal resistance against Pst are both inherited as dominant traits. Analysis of the F2 and F3 progeny of a Col × RLD cross revealed that inducibility of ISR and relatively high basal resistance against Pst cosegregate in a 3 : 1 fashion, suggesting that both resistance mechanisms are monogenically determined and genetically linked. Neither the responsiveness to WCS417r nor the relatively high level of basal resistance against Pst were complemented in the F1 progeny of crosses between RLD and Ws, indicating that RLD and Ws are both affected in the same locus, necessary for the expression of ISR and basal resistance against Pst. The corresponding locus, designated ISR1, was mapped between markers B4 and GL1 on chromosome 3. The observed association between ISR and basal resistance against Pst suggests that rhizo-bacteria-mediated ISR against Pst in Arabidopsis requires the presence of a single dominant gene that functions in the basal resistance response against Pst infection.

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Analysis of cDNA library of Cucumis sativus L. challenged by Pseudomonas syringae pv. Lachrymans

Hereditas (Beijing) ◽

10.3724/sp.j.1005.2009.01042 ◽

2009 ◽

Vol 31 (10) ◽

pp. 1042-1048

Author(s):

Guan-Jun LIU ◽

Li-Juan WANG ◽

Zhi-Wei QIN ◽

Ling-Bo MENG

Keyword(s):

Cdna Library ◽

Cucumis Sativus ◽

Pseudomonas Syringae

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Comparative Mapping of Three Bacterial, Three Fungal, and One Virus Disease-resistance Genes in Common Bean

HortScience ◽

10.21273/hortsci.33.3.547a ◽

1998 ◽

Vol 33 (3) ◽

pp. 547a-547

Author(s):

Geunhwa Jung ◽

James Nienhuis ◽

Dermot P. Coyne ◽

H.M. Ariyarathne

Keyword(s):

Disease Resistance ◽

Common Bean ◽

Pseudomonas Syringae ◽

Resistance Genes ◽

Fungal Pathogens ◽

Xanthomonas Campestris ◽

Virus Disease ◽

Disease Resistance Genes ◽

Brown Spot ◽

Viral Pathogen

Common bacterial blight (CBB), bacterial brown spot (BBS), and halo blight (HB), incited by the bacterial pathogens Xanthomonas campestris pv. phaseoli (Smith) Dye, Pseodomonas syringae pv. syringa, and Pseudomonas syringae pv. phaseolicola, respectively are important diseases of common bean. In addition three fungal pathogens, web blight (WB) Thanatephorus cucumeris, rust Uromyces appendiculatus, and white mold (WM) Sclerotinia sclerotiorum, are also destructive diseases attacking common bean. Bean common mosaic virus is also one of most major virus disease. Resistance genes (QTLs and major genes) to three bacterial (CBB, BBS, and HB), three fungal (WB, rust, and WM), and one viral pathogen (BCMV) were previously mapped in two common bean populations (BAC 6 × HT 7719 and Belneb RR-1 × A55). The objective of this research was to use an integrated RAPD map of the two populations to compare the positions and effect of resistance QTL in common bean. Results indicate that two chromosomal regions associated with QTL for CBB resistance mapped in both populations. The same chromosomal regions associated with QTL for disease resistance to different pathogens or same pathogens were detected in the integrated population.

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Uncoupling Salicylic Acid-Dependent Cell Death and Defense-Related Responses From Disease Resistance in the Arabidopsis Mutant acd5

Genetics ◽

10.1093/genetics/156.1.341 ◽

2000 ◽

Vol 156 (1) ◽

pp. 341-350

Author(s):

Jean T Greenberg ◽

F Paul Silverman ◽

Hua Liang

Keyword(s):

Cell Death ◽

Salicylic Acid ◽

Disease Resistance ◽

Pseudomonas Syringae ◽

Higher Plants ◽

Ethylene Signaling ◽

Symptom Development ◽

Wild Type ◽

Dependent Cell ◽

Arabidopsis Mutant

Abstract Salicylic acid (SA) is required for resistance to many diseases in higher plants. SA-dependent cell death and defense-related responses have been correlated with disease resistance. The accelerated cell death 5 mutant of Arabidopsis provides additional genetic evidence that SA regulates cell death and defense-related responses. However, in acd5, these events are uncoupled from disease resistance. acd5 plants are more susceptible to Pseudomonas syringae early in development and show spontaneous SA accumulation, cell death, and defense-related markers later in development. In acd5 plants, cell death and defense-related responses are SA dependent but they do not confer disease resistance. Double mutants with acd5 and nonexpressor of PR1, in which SA signaling is partially blocked, show greatly attenuated cell death, indicating a role for NPR1 in controlling cell death. The hormone ethylene potentiates the effects of SA and is important for disease symptom development in Arabidopsis. Double mutants of acd5 and ethylene insensitive 2, in which ethylene signaling is blocked, show decreased cell death, supporting a role for ethylene in cell death control. We propose that acd5 plants mimic P. syringae-infected wild-type plants and that both SA and ethylene are normally involved in regulating cell death during some susceptible pathogen infections.

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Identification of Three Putative Signal Transduction Genes Involved in R Gene-Specified Disease Resistance in Arabidopsis

Genetics ◽

10.1093/genetics/152.1.401 ◽

1999 ◽

Vol 152 (1) ◽

pp. 401-412 ◽

Cited By ~ 1

Author(s):

Randall F Warren ◽

Peter M Merritt ◽

Eric Holub ◽

Roger W Innes

Keyword(s):

Disease Resistance ◽

Pseudomonas Syringae ◽

Resistance Genes ◽

Virulent Strain ◽

Disease Resistance Genes ◽

Avirulence Gene ◽

Detectable Effect ◽

Disease Resistance Gene ◽

Protein Functions ◽

Signal Transduction Genes

Abstract The RPS5 disease resistance gene of Arabidopsis mediates recognition of Pseudomonas syringae strains that possess the avirulence gene avrPphB. By screening for loss of RPS5-specified resistance, we identified five pbs (avrPphB susceptible) mutants that represent three different genes. Mutations in PBS1 completely blocked RPS5-mediated resistance, but had little to no effect on resistance specified by other disease resistance genes, suggesting that PBS1 facilitates recognition of the avrPphB protein. The pbs2 mutation dramatically reduced resistance mediated by the RPS5 and RPM1 resistance genes, but had no detectable effect on resistance mediated by RPS4 and had an intermediate effect on RPS2-mediated resistance. The pbs2 mutation also had varying effects on resistance mediated by seven different RPP (recognition of Peronospora parasitica) genes. These data indicate that the PBS2 protein functions in a pathway that is important only to a subset of disease-resistance genes. The pbs3 mutation partially suppressed all four P. syringae-resistance genes (RPS5, RPM1, RPS2, and RPS4), and it had weak-to-intermediate effects on the RPP genes. In addition, the pbs3 mutant allowed higher bacterial growth in response to a virulent strain of P. syringae, indicating that the PBS3 gene product functions in a pathway involved in restricting the spread of both virulent and avirulent pathogens. The pbs mutations are recessive and have been mapped to chromosomes I (pbs2) and V (pbs1 and pbs3).

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