Methyl salicylate production in tomato affects biotic interactions: Role of methyl salicylate in tomato defence

Department of Plant Physiology, Swammerdam Institute for Life Sciences, Science Park 904, 1098 XH, Amsterdam, the Netherlands.
The Plant Journal (Impact Factor: 6.82). 04/2010; 62(1):124-34. DOI: 10.1111/j.1365-313X.2010.04132.x
Source: PubMed

ABSTRACT The role of methyl salicylate (MeSA) production was studied in indirect and direct defence responses of tomato (Solanum lycopersicum) to the spider mite Tetranychus urticae and the root-invading fungus Fusarium oxysporum f. sp. lycopersici, respectively. To this end, we silenced the tomato gene encoding salicylic acid methyl transferase (SAMT). Silencing of SAMT led to a major reduction in SAMT expression and MeSA emission upon herbivory by spider mites, without affecting the induced emission of other volatiles (terpenoids). The predatory mite Phytoseiulus persimilis, which preys on T. urticae, could not discriminate between infested and non-infested SAMT-silenced lines, as it could for wild-type tomato plants. Moreover, when given the choice between infested SAMT-silenced and infested wild-type plants, they preferred the latter. These findings are supportive of a major role for MeSA in this indirect defence response of tomato. SAMT-silenced tomato plants were less susceptible to a virulent strain of F. oxysporum f. sp. lycopersici, indicating that the direct defense responses in the roots are also affected in these plants. Our studies show that the conversion of SA to MeSA can affect both direct and indirect plant defence responses.

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Available from: Frank Takken, Nov 25, 2014
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    • "Salicylic acid methyltransferase from P. brassicae 357 Fusarium oxysporum (Ament et al., 2010). In accordance with a function for SA in defence against P. brassicae, treatment of Arabidopsis roots with 0.5 mM SA before inoculation completely reduced clubroot symptoms (Agarwal et al., 2011). "
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    Molecular Plant Pathology 08/2014; 16(4). DOI:10.1111/mpp.12185 · 4.49 Impact Factor
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    • "RNAi silencing constructs were designed to silence simultaneously the genes of interest as well as a GUS reporter gene. The latter can be transiently expressed in leaves of stable transformants by agroinfiltration to simplify screening for plants exhibiting strong silencing (Wroblewski et al., 2007; Ament et al. 2010; Krasikov et al. 2010). For each gene two constructs were created that targetted either the 3# or the 5# end of the transcribed gene sequence. "
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    • "This supports its purported role as a universal lure for beneficial insects used in the biocontrol of agricultural pests (e.g., PredaLure). It also substantiates the outcomes from laboratory preference assays, which document that natural enemies frequently orient toward this volatile when offered a choice in foraging arenas (De Boer and Dicke, 2004, 2005; Ishiwari et al., 2007; Sasso et al., 2009; Ament et al., 2010; Shimoda, 2010). "
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