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PubMed · 11171239

Differential signalling and plant-volatile biosynthesis.

J Engelberth
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Abstract

At least two different signalling pathways have been identified that result in clearly distinguishable volatile profiles in response to pathogens and herbivores in the lima bean Phaseolus lunatus. Alamethicin, a voltage-gated ion-channel-forming peptide from Trichoderma viride, is a potent inducer of volatile biosynthesis in the lima bean. Unlike elicitation with cellulysin or herbivore damage, which act through the jasmonic acid pathway and result in a complex pattern of volatile compounds, the emitted blend comprises only the two homoterpens, 4,11-dimethylnona-1,3,7-triene and 4,8,12-trimethyltrideca-1,3,7,11-tetraene, and methyl salicylate. Both pathways, represented by jasmonic acid and alamethicin, depend on lipid-derived signalling compounds, set off by the activation of a phospholipase A and further processing by lipoxygenase activity. The alamethicin-induced signal-transduction pathway interferes with the octadecanoid cascade, probably due to increased salicylic acid levels, resulting in an inhibition of the typical jasmonic acid-induced volatile profile.

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AlamethicinFabaceaePlants, MedicinalSalicylatesSignal TransductionTerpenesJournal Article

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J Engelberth. 2000. Differential signalling and plant-volatile biosynthesis.. https://pubmed.ncbi.nlm.nih.gov/11171239/

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