Attacks by a piercing-sucking insect (Myzus persicae Sultzer) or a chewing insect (Leptinotarsa decemlineata Say) on potato plants (Solanum tuberosum L.) induce differential changes in volatile compound release and oxylipin synthesis

Abstract

Plant defensive strategies bring into play blends of compounds dependent on the type of attacker and coming from different synthesis pathways. Interest in the field is mainly focused on volatile organic compounds (VOCs) and jasmonic acid (JA). By contrast, little is known about the oxidized polyunsaturated fatty acids (PUFAs), such as PUFA-hydroperoxides, PUFA-hydroxides, or PUFA-ketones. PUFA-hydroperoxides and their derivatives might be involved in stress response and show antimicrobial activities. Hydroperoxides are also precursors of JA and some volatile compounds. In this paper, the differential biochemical response of a plant against insects with distinct feeding behaviours is characterized not only in terms of VOC signature and JA profile but also in terms of their precursors synthesized through the lipoxygenase (LOX)-pathway at the early stage of the plant response. For this purpose, two leading pests of potato with distinct feeding behaviours were used: the Colorado Potato Beetle (Leptinotarsa decemlineata Say), a chewing herbivore, and the Green Peach Aphid (Myzus persicae Sulzer), a piercing-sucking insect. The volatile signatures identified clearly differ in function with the feeding behaviour of the attacker and the aphid, which causes the smaller damages, triggers the emission of a higher number of volatiles. In addition, 9-LOX products, which are usually associated with defence against pathogens, were exclusively activated by aphid attack. Furthermore, a correlation between volatiles and JA accumulation and the evolution of their precursors was determined. Finally, the role of the insect itself on the plant response after insect infestation was highlighted.

Root-Derived Oxylipins Promote Green Peach Aphid Performance on Arabidopsis Foliage

“…The GPA Population Size Is Smaller in lox5 Mutant Plants Than in Wild-Type Arabidopsis Plants Accumulation of 9-LOX-synthesized oxylipins and volatile compounds derived from these oxylipins was previously shown to be stimulated in leaves of plants infested with aphids (Gosset et al, 2009). Some 9-LOX-derived volatiles induce oviposition in aphid predators (Verheggen et al, 2008), thus implicating a potential role for 9-LOXs in indirect defense against aphids.…”

Loss of Function of FATTY ACID DESATURASE7 in Tomato Enhances Basal Aphid Resistance in a Salicylate-Dependent Manner

“…However, fatty acids have been proposed to participate in defense signaling either directly or indirectly and are also precursors for the synthesis of azelaic acid and numerous oxylipins that contribute to plant immunity (Blée, 2002;Jung et al, 2009). For example, a study in potato demonstrated that aphids strongly induce the production of 9-hydroperoxy-octadecadienoic acid, a derivative of linoleic acid synthesized by 9-lipoxygenases (Gosset et al, 2009). Potentially, increases in 9-hydroperoxyoctadecadienoic acid or other oxylipin derivatives of linoleic acid may contribute to aphid resistance in spr2.…”

Beetle feeding induces a different volatile emission pattern from black poplar foliage than caterpillar herbivory

“…5 Insects from different feeding guilds (e.g., sucking, chewing, mining or galling insects) are especially reported to induce different volatile blends. [6][7][8] These differential plant responses are thought to be due to differences in the elicitors present in insect oral secretions, in the mode of feeding, or in the host specificity of the insects or the timing of attack. 9 However, most evidence for herbivore species-specific volatile emission comes from short lived herbaceous species.…”