Volatile organic compound emissions in Myzus persicae resistant and susceptible peach cultivars

Volatile compounds from plants play a central role in plant-environment interaction phenomena, being involved in key life processes such as reproduction, defense and communication. They are produced in normal metabolic processes as well as in response to biotic and abiotic stresses. In particular, volatiles exert an important role in shaping plant-insect interactions, for instance acting as pollinators and seed dispersers attractants. The study of plant-insect interaction mechanisms represents an important topic for many scientists, because of the economic implications in agricultural, environmental and ecological fields. Our attention was focused on Volatile Organic Compounds (VOCs) emissions from leaf of different peach cultivars (Prunus persica (L.) Batsch) susceptible or resistant to the green peach aphid, Myzus persicae (Sulzer), one of the major pests in peach farming. A Headspace Solid-Phase-Microextraction coupled with Gas-Chromatography/Mass Spectrometry (HS-SPME-GC/MS) method was used to study the volatile compounds profile emitted from the different peach cultivars. Several differences in emitted VOCs were observed among peach genotipes. Benzaldehyde, (Z)-3-hexenyl acetate, 2-hexenal, methyl benzoate, ethyl benzoate, trans-2-hexen-1-ol were the most abundant volatile compounds isolated from the sample headspaces. Many of these compounds are known as Green Leaf Volatiles (GLV) typically released from damaged leaves and used as kairomones by many herbivorous insects for host plant location. Benzaldehyde, 2-hexenal, trans-2-hexen-1-ol and trans-caryophyllene showed a decreasing trend from the resistant to the susceptible genotypes; at the opposite, 3-hexen-1-ol acetate seems to be higher in the susceptible genotypes. This approach could give a contribute in finding new strategies to limit insect pests in an ecologically friendly way, improving both environment and production quality