ABA Suppresses Botrytis cinerea Elicited NO Production in Tomato to Influence H2O2 Generation and Increase Host Susceptibility

Abstract

Abscisic acid (ABA) production has emerged a susceptibility factor in plant-pathogen interactions. This work examined the interaction of ABA with nitric oxide (NO) in tomato following challenge with the ABA-synthesizing pathogen, Botrytis cinerea. Trace gas detection using a quantum cascade laser detected NO production within minutes of challenge with B. cinerea whilst photoacoustic laser detection detected ethylene production – an established mediator of defense against this pathogen – occurring after 6 h. Application of the NO generation inhibitor N-Nitro-L-arginine methyl ester (L-NAME) suppressed both NO and ethylene production and resistance against B. cinerea. The tomato mutant sitiens fails to accumulate ABA, shows increased resistance to B. cinerea and we noted exhibited elevated NO and ethylene production. Exogenous application of L-NAME or ABA reduced NO production in sitiens and reduced resistance to B. cinerea. Increased resistance to B. cinerea in sitiens have previously been linked to increased reactive oxygen species (ROS) generation but this was reduced in both L-NAME and ABA-treated sitiens. Taken together, our data suggests that ABA can decreases resistance to B. cinerea via reduction of NO production which also suppresses both ROS and ethylene production.

Transcriptome analysis and functional validation reveal a novel gene, BcCGF1, that enhances fungal virulence by promoting infection‐related development and host penetration

“…Cytochrome P450 monooxygenases are essential for ABA biosynthesis in B. cinerea (Siewers et al, 2004). ABA decreases tomato resistance to B. cinerea via reduction of NO production, which also suppresses both ROS and ET production (Sivakumaran et al, 2016). Two P450 monooxygenase genes (BCIN_07g05430 and BCIN_03g06490) involved in ABA biosynthesis in B. cinerea were upregulated (Table S5).…”

“…Plant responses to B. cinerea infection include host cell death, production of various secondary metabolites, antimicrobial peptides, and hormones, for example ethylene (ET), salicylic acid (SA), abscisic acid (ABA), and jasmonate (JA), as well as accumulation of reactive oxygen species (ROS), callose, and a variety of other cell wall modifications (Mengiste, 2012). ABA, ET, and auxin, are known to be actively involved in plant defence against B. cinerea (Navarro et al, 2006;El Oirdi et al, 2011;Windram et al, 2012;Sivakumaran et al, 2016). Other phytohormones, for example brassinosteroids, also regulate plant immunity by mainly interacting with transcription factors, or through camalexin biosynthesis and callose deposition.…”

Tomato SlERF.A1, SlERF.B4, SlERF.C3 and SlERF.A3, Members of B3 Group of ERF Family, Are Required for Resistance to Botrytis cinerea

“…Shortening in JA biosynthesis resulted in increased susceptibility to B. cinerea (Hind et al, 2011; Zhang S. et al, 2015), whereas ET-mediated signaling plays a positive role in immunity to B. cinerea (Francia et al, 2007; Lin et al, 2008; Nambeesan et al, 2012). It was shown that ABA regulates the immunity to B. cinerea in tomato through modulating the cuticle permeability and pectin composition in cell wall or suppressing the SA-mediated signaling pathway or the production of nitric oxide (Audenaert et al, 2002; Asselbergh et al, 2007; Curvers et al, 2010; Sivakumaran et al, 2016). A number of genes encoding receptor-like protein kinase TPK1b, transcriptional factors SHINE3, AIM1, SlDRW1, SlSRN1, SlSR1, and SlSR3L (Abuqamar et al, 2008, 2009; Buxdorf et al, 2014; Li et al, 2014a; Liu et al, 2014a,b), histone H2B monoubiquitination enzymes SlHUB1 and SlHUB2 (Zhang Y. et al, 2015), mitogen-activated protein kinase kinase SlMKK2 and SlMKK4 (Li et al, 2014b), phosphatidylinositol-phospholipase SlPLC2 (Gonorazky et al, 2016), NADPH oxidase SlRbohB (Li X. et al, 2015), 12-oxophytodienoate reductase SlOPR3 (Scalschi et al, 2015) and matrix metalloproteinase Sl3-MMP (Li D. et al, 2015) have been identified to play important roles in tomato immunity against B. cinerea .…”

<i>n</i>-Propyl dihydrojasmonates influence ethylene signal transduction in infected apple fruit by <i>Botrytis cinerea</i>

“…ABA treatment increased the pathogen resistance of fruit (Sivakumaran et al, 2016;Lievens et al, 2017). Wang et al (2015b) reported that PDJ application increased the endogenous ABA and JA concentrations in inoculated 'Kyoho' grape berries.…”