Epirrita autumnata induced VOC emission of silver birch differ from emission induced by leaf fungal pathogen

Abstract

The production of volatile organic compounds (VOCs) through the activation of different signaltransduction pathways may be induced in various biotic and abiotic stress situations having importance e.g. in insect and disease resistance. We compared the emission of VOCs emitted from silver birch Betula pendula Roth (clones 4 and 80) twigs damaged either by larvae of Epirrita autumnata, or infected with pathogenic leaf spot causing fungus Marssonina betulae. We also analysed whether local herbivore damage can systemically induce the release of VOCs from the undamaged top of same sapling. The emissions of methylsalicylate (MeSA), (Z)-ocimene, (E)-b-ocimene, (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT) and linalool were induced from the twigs after 72 h feeding damage by E. autumnata larvae. However, 48 h feeding damage did not induce rapid systemic release of VOCs from undamaged top leaves of the same twigs. Pathogen-infected birch twigs had significantly greater emission of (Z)-ocimene and (E)-b-ocimene than intact control twigs. The emission of DMNT was not significantly induced and MeSA was not found at all after pathogen infection, both being significantly different from herbivore damaged twigs. According to our results leaf fungal pathogen induces VOC emission profile differs from that of arthropod herbivore-damaged leaves, suggesting that birch is able to transmit parasite-specific information via VOC emissions to conspecifics and natural enemies of herbivores.

The leaf-level emission factor of volatile isoprenoids: caveats, model algorithms, response shapes and scaling

“…Yet, emissions of volatile compounds can be triggered by various biotic and abiotic stress factors in essentially all plant species (Arimura et al, 2009;Brilli et al, 2009;Wu and Baldwin, 2009). Furthermore, foliage sesquiterpene emissions are mostly associated with stress (Duhl et al, 2008;Hakola et al, 2006), and emissions of homoterpenes, C 11 compound DMNT (4,8-dimethylnona-1,3,7-triene) and C 16 compound TMTT (4,8,3,7, are exclusively associated with stress, in particular, with biotic stress (Arimura et al, 2009;Herde et al, 2008;Vuorinen et al, 2007;Wu and Baldwin, 2009). The stress-driven monoterpene emissions are often dominated by specific stress-marker compounds such as the oxygenated monoterpenes linalool and non-oxygenated ocimenes Cardoza et al, 2002;Martin et al, 2003;Pinto et al, 2007;Staudt and Bertin, 1998;Staudt et al, 2003).…”

Potential for the Use of Exogenous Chemical Elicitors in Disease and Insect Pest Management of Conifer Seedling Production

“…Tissue concentrations and volatile emissions of organic compounds may both be elevated, but re-sponsiveness of different compounds depends on the type of attacking organism e.g. [10].…”

Importance of olfactory and visual signals of autumn leaves in the coevolution of aphids and trees

“…(45) Plants respond to herbivory by increasing production of volatile compounds that attract carnivores. (46) Two major groups of compounds can be detected from herbivore-damaged plants (47,48) terpenes that are formed from five-carbon isoprenoid units, and six-carbon compounds produced via the lipoxygenase (LOX) pathway, called green leaf volatiles (GLVs). GLVs mainly comprise saturated or monounsaturated aldehydes, alcohols and esters, they are released rapidly after damage and dominate the emissions from mechanically damaged plant parts.…”