scholarly journals Tomato Susceptibility to Root-Knot Nematodes Requires an Intact Jasmonic Acid Signaling Pathway

2008 ◽  
Vol 21 (9) ◽  
pp. 1205-1214 ◽  
Author(s):  
Kishor K. Bhattarai ◽  
Qi-Guang Xie ◽  
Sophie Mantelin ◽  
Usha Bishnoi ◽  
Thomas Girke ◽  
...  

Responses of resistant (Mi-1/Mi-1) and susceptible (mi-1/ mi-1) tomato (Solanum lycopersicum) to root-knot nematodes (RKNs; Meloidogyne spp.) infection were monitored using cDNA microarrays, and the roles of salicylic acid (SA) and jasmonic acid (JA) defense signaling were evaluated in these interactions. Array analysis was used to compare transcript profiles in incompatible and compatible interactions of tomato roots 24 h after RKN infestation. The jai1 and def1 tomato mutant, altered in JA signaling, and tomato transgenic line NahG, altered in SA signaling, in the presence or absence of the RKN resistance gene Mi-1, were evaluated. The array analysis identified 1,497 and 750 genes differentially regulated in the incompatible and compatible interactions, respectively. Of the differentially regulated genes, 37% were specific to the incompatible interactions. NahG affected neither Mi-1 resistance nor basal defenses to RKNs. However, jai1 reduced tomato susceptibility to RKNs while not affecting Mi-1 resistance. In contrast, the def1 mutant did not affect RKN susceptibility. These results indicate that JA-dependent signaling does not play a role in Mi-1-mediated defense; however, an intact JA signaling pathway is required for tomato susceptibility to RKNs. In addition, low levels of SA might be sufficient for basal and Mi-1 resistance to RKNs.

2020 ◽  
Vol 21 (4) ◽  
pp. 1446 ◽  
Author(s):  
Jia Wang ◽  
Li Song ◽  
Xue Gong ◽  
Jinfan Xu ◽  
Minhui Li

Jasmonic acid (JA) is an endogenous growth-regulating substance, initially identified as a stress-related hormone in higher plants. Similarly, the exogenous application of JA also has a regulatory effect on plants. Abiotic stress often causes large-scale plant damage. In this review, we focus on the JA signaling pathways in response to abiotic stresses, including cold, drought, salinity, heavy metals, and light. On the other hand, JA does not play an independent regulatory role, but works in a complex signal network with other phytohormone signaling pathways. In this review, we will discuss transcription factors and genes involved in the regulation of the JA signaling pathway in response to abiotic stress. In this process, the JAZ-MYC module plays a central role in the JA signaling pathway through integration of regulatory transcription factors and related genes. Simultaneously, JA has synergistic and antagonistic effects with abscisic acid (ABA), ethylene (ET), salicylic acid (SA), and other plant hormones in the process of resisting environmental stress.


2019 ◽  
Vol 20 (12) ◽  
pp. 2917 ◽  
Author(s):  
Yuya Uji ◽  
Keita Kashihara ◽  
Haruna Kiyama ◽  
Susumu Mochizuki ◽  
Kazuya Akimitsu ◽  
...  

Jasmonic acid (JA) is a plant hormone that plays an important role in the defense response and stable growth of rice. In this study, we investigated the role of the JA-responsive valine-glutamine (VQ)-motif-containing protein OsVQ13 in JA signaling in rice. OsVQ13 was primarily located in the nucleus and cytoplasm. The transgenic rice plants overexpressing OsVQ13 exhibited a JA-hypersensitive phenotype and increased JA-induced resistance to Xanthomonas oryzae pv. oryzae (Xoo), which is the bacteria that causes rice bacterial blight, one of the most serious diseases in rice. Furthermore, we identified a mitogen-activated protein kinase, OsMPK6, as an OsVQ13-associating protein. The expression of genes regulated by OsWRKY45, an important WRKY-type transcription factor for Xoo resistance that is known to be regulated by OsMPK6, was upregulated in OsVQ13-overexpressing rice plants. The grain size of OsVQ13-overexpressing rice plants was also larger than that of the wild type. These results indicated that OsVQ13 positively regulated JA signaling by activating the OsMPK6–OsWRKY45 signaling pathway in rice.


Nematology ◽  
2007 ◽  
Vol 9 (3) ◽  
pp. 363-370 ◽  
Author(s):  
Keith Davies ◽  
Ioannis Vagelas ◽  
Simon Gowen ◽  
Barbara Pembroke

AbstractPseudomonas oryzihabitans, a bacterium associated with the entomopathogenic nematode Steinernema abbasi, was evaluated for its potential to colonise roots and thereby control a field population of root-knot nematodes. Immunological techniques were developed to detect root colonisation of P. oryzihabitans on tomato roots using a specific polyclonal antibody raised against vegetative bacterial cells. In vitro, bacterial cell filtrates were also shown significantly to inhibit juveniles hatching. In a glasshouse pot experiment, there were 22 and 82% fewer females in roots of plants treated with suspensions containing 103 and 106 cells ml−1 of P. oryzihabitans, respectively. In addition, there were significantly fewer egg masses produced; however, the numbers of eggs per egg mass did not differ significantly. The relationship between root colonisation and nematode control is discussed.


2021 ◽  
Author(s):  
Yutao Zhu ◽  
Xiaoqian Hu ◽  
Yujiao Jia ◽  
Linying Gao ◽  
Yakun Pei ◽  
...  

Abstract Patatin-like proteins (PLPs) have nonspecific lipid acyl hydrolyze (LAH) activity, which can hydrolyze membrane lipids into fatty acids and lysophospholipids. The vital role of PLPs in plant growth and abiotic stress has been well elucidated. However, the function of PLPs in plant defense response against pathogens is still poorly understood. Here, we isolated and identified a novel cotton (Gossypium hirsutum) patatin-like protein gene GhPLP2. GhPLP2 expression was induced upon treatment with pathogens Verticillium dahliae, Fusarium xysporum, and signaling molecules jasmonic acid (JA), ethylene in cotton plants. Subcellular localization revealed that GhPLP2 was localized in the cell wall and plasma membrane. GhPLP2-silenced cotton plants showed reduced resistance to V. dahliae infection, while overexpression of GhPLP2 in Arabidopsis enhanced the resistance to V. dahliae, with mild symptoms, decreased disease index, and fungal biomass. Hypersensitive response, callose deposition, and H2O2 accumulation triggered by V. dahlia elicitor were reduced in silenced cotton plants. GhPLP2-transgenic Arabidopsis had more accumulation of JA and JA synthesis precursor linoleic acid (LA, 18:2) and α-linolenic acid (ALA, 18:3) than control plants. Consistently, linoleic acid, α-linolenic acid, and jasmonic acid have decreased in GhPLP2-silenced cotton plants. Further, the gene expression of the JA signaling pathway is up-regulated in transgenic Arabidopsis and down-regulated in silenced cotton plants, respectively. These results showed that GhPLP2 is involved in plants' resistance to V. dahliae by maintaining fatty acid metabolism pools for JA biosynthesis and activation of the JA signaling pathway.


2007 ◽  
Vol 20 (3) ◽  
pp. 276-282 ◽  
Author(s):  
Kishor K. Bhattarai ◽  
Qi-Guang Xie ◽  
Daniel Pourshalimi ◽  
Ted Younglove ◽  
Isgouhi Kaloshian

Tomato (Solanum lycopersicum) has a unique resistance gene, Mi-1, that confers resistance to animals from distinct taxa, nematodes, and piercing and sucking insects. Mi-1 encodes a protein with a nucleotide-binding site and leucine-rich repeat motifs. Early in the potato aphid (Macrosiphum euphorbiae)—tomato interactions, aphid feeding induces the expression of the jasmonic acid (JA)-regulated proteinase inhibitor genes, Pin1 and Pin2. The jai1-1 (jasmonic acid insensitive 1) tomato mutant, which is impaired in JA perception, was used to gain additional insight into the JA signaling pathway and its role in the Mi-1—mediated aphid resistance. The jai1-1 mutant has a deletion in the Coi1 gene that encodes a putative F-box protein. In this study, aphid colonization, survival, and fecundity were compared on wild-type tomato and jai1-1 mutant. In choice assays, the jai1-1 mutant showed higher colonization by potato aphids compared with wild-type tomato. In contrast, no-choice assays showed no difference in potato aphid survival or fecundity between jai1-1 and the wild-type parent. Plants homozygous for Mi-1 and for the jai1 mutation were not compromised in resistance to potato aphids, using either choice or no-choice assays. In addition, the accumulation of JA-regulated Pin1 transcripts after aphid feeding was Coi1 dependent. Taken together, these data indicate that, although potato aphids activate Coi1-dependent defense response in tomato, this response is not required for Mi-1—mediated resistance to aphids.


Planta ◽  
2021 ◽  
Vol 254 (1) ◽  
Author(s):  
Bipin K. Pandey ◽  
Lokesh Verma ◽  
Ankita Prusty ◽  
Ajit Pal Singh ◽  
Malcolm J. Bennett ◽  
...  

Abstract Main conclusion OsJAZ11 regulates phosphate homeostasis by suppressing jasmonic acid signaling and biosynthesis in rice roots. Abstract Jasmonic Acid (JA) is a key plant signaling molecule which negatively regulates growth processes including root elongation. JAZ (JASMONATE ZIM-DOMAIN) proteins function as transcriptional repressors of JA signaling. Therefore, targeting JA signaling by deploying JAZ repressors may enhance root length in crops. In this study, we overexpressed JAZ repressor OsJAZ11 in rice to alleviate the root growth inhibitory action of JA. OsJAZ11 is a low phosphate (Pi) responsive gene which is transcriptionally regulated by OsPHR2. We report that OsJAZ11 overexpression promoted primary and seminal root elongation which enhanced Pi foraging. Expression studies revealed that overexpression of OsJAZ11 also reduced Pi starvation response (PSR) under Pi limiting conditions. Moreover, OsJAZ11 overexpression also suppressed JA signaling and biosynthesis as compared to wild type (WT). We further demonstrated that the C-terminal region of OsJAZ11 was crucial for stimulating root elongation in overexpression lines. Rice transgenics overexpressing truncated OsJAZ11ΔC transgene (i.e., missing C-terminal region) exhibited reduced root length and Pi uptake. Interestingly, OsJAZ11 also regulates Pi homeostasis via physical interaction with a key Pi sensing protein, OsSPX1. Our study highlights the functional connections between JA and Pi signaling and reveals JAZ repressors as a promising candidate for improving low Pi tolerance of elite rice genotypes.


Nematology ◽  
2017 ◽  
Vol 19 (1) ◽  
pp. 69-80 ◽  
Author(s):  
Israel L. Medina ◽  
Cesar B. Gomes ◽  
Valdir R. Correa ◽  
Vanessa S. Mattos ◽  
Philippe Castagnone-Sereno ◽  
...  

Root-knot nematodes (Meloidogyne spp.) significantly impact potato production worldwide and in Brazil they are considered one of the most important group of nematodes affecting potatoes. The objectives of this study were to survey Meloidogyne spp. associated with potatoes in Brazil, determine their genetic diversity and assess the aggressiveness of M. javanica on two susceptible potato cultivars. Fifty-seven root-knot nematode populations were identified using esterase phenotyping, including Meloidogyne javanica, M. incognita, M. arenaria and M. ethiopica. Overall, root-knot nematodes were present in ca 43% of sampled sites, in which M. javanica was the most prevalent species, and the phenotypes Est J3, J2a and J2 occurred in 91.2, 6.7 and 2.1% of the positive samples, respectively. Other species, such as M. incognita, M. arenaria and M. ethiopica, were found less frequently and occurred at rates of 6.4, 4.3 and 2.1% of the samples, respectively. Sometimes, M. javanica was found in mixtures with other root-knot nematodes in ca 10.6% of sites containing Meloidogyne. After confirming the identification of 17 isolates of M. javanica and one isolate each of M. incognita, M. arenaria and M. ethiopica by SCAR markers, the populations were used to infer their genetic diversity using RAPD markers. Results revealed low intraspecifc genetic diversity among isolates (13.9%) for M. javanica. Similarly, M. javanica sub-populations (J2a) clustered together (81% of bootstrap), indicating subtle variation from typical J3 populations. The aggressiveness of four populations of M. javanica from different Brazilian states on two susceptible potato cultivars was tested under glasshouse conditions. Results indicated differences in aggressiveness among these populations and showed that potato disease was proportional to nematode reproduction factor.


Nematology ◽  
2000 ◽  
Vol 2 (8) ◽  
pp. 907-916 ◽  
Author(s):  
Ngo Thi Xuyen ◽  
Raf Verlinden ◽  
Ruth Stoffelen ◽  
Dirk De Waele ◽  
Rony Swennen

AbstractTwenty-five banana varieties of section Eumusa (AA-group) and seven of the section Australimusa (Fe'i-group) from Papua New Guinea were evaluated for resistance to Radopholus similis, Pratylenchus coffeae and Meloidogyne spp. The host plant responses were compared with the susceptible reference cvs Grande Naine and Cavendish 901. In vitro propagated plants were transferred to the glasshouse in loamy sand and inoculated with approximately 1000 migratory endoparasitic nematodes at 4 weeks after planting. Reproduction of R. similis and P.coffeae in the roots was determined at 8 or 10 weeks, respectively, after inoculation. Reproduction of Meloidogyne spp. was determined 8 weeks after inoculation with 3300 to 5000 eggs. No resistance to R. similis was found in the diploid varieties. The Fe'i variety Rimina and possibly Menei were resistant to R. similis. All varieties tested were susceptible to P.coffeae and Meloidogyne spp. Tests de résistance de bananiers Eumusa et Australimusa (Musa spp.) envers les nématodes endoparasites migrateurs et galligènes - Vingt-cinq variétés de bananier de la section Eumusa (groupe AA) et sept de la section Australimusa (group Fe'i) provenant de Papouasie-Nouvelle Guinée ont été testées pour leur résistance envers Radopholus similis, Pratylenchus coffeae et Meloidogyne spp. Les résponses de ces variétés ont été comparées à celles des cultivars sensibles de référence Grande Naine et Cavendish 901. Des vitroplants ont été mis en place en serre sur un sol argilo-sableux et inoculés 4 semaines après plantation avec environ 1000 R. similis ou P.coffeae dont la reproduction a été déterminée 8 et 10 semaines, respectivement, après inoculation. La reproduction de Meloidogyne spp. l'a été 8 semaines après inoculation avec 3300 à 5000 oeufs. Aucune résistance à R. similis n'a été observée chez les variétés diploïdes. Les variétés du groupe Fe'i Rimina et Menei se sont montrées résistantes à R. similis, avec un certain doute dans le cas de la dernière. Toutes les variétés testées sont sensibles à P.coffeae et Meloidogyne spp.


Sign in / Sign up

Export Citation Format

Share Document