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: 5.97). 04/2010; 62(1):124-34. DOI: 10.1111/j.1365-313X.2010.04132.x
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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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    • "Elicitors including methyl salicylate, and chitosan as well as NaCl were utilized to stimulate the plant stress response to increase the anti-diabetic activity of W. somnifera. Methyl salicylate and chitosan have been shown to be very effective at inducing the plant defense response (Ament et al., 2010; El Hadrami et al., 2010). Methyl salicylate is a natural plant derivative of salicylic acid implicated as an airborne signal involved with systemic acquired resistance (Shah et al., 2014). "
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    Phytochemistry 03/2015; 116(1). DOI:10.1016/j.phytochem.2015.02.029 · 2.55 Impact Factor
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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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    • "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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