The Influence of Pine Volatile Compounds on the Olfactory Response by Neodiprion sertifer (Geoffroy) Females

Abstract

Females of the pine sawfly Neodiprion sertifer (Hymenoptera Diprionidae) usually avoid Pinus pinea trees as host plants. In contrast, this sawfly species is highly attracted by P. sylvestris and P. nigra trees. Here, we investigated which pine volatiles might mediate this behavior by in situ sampling experiments and olfactometer laboratory tests. Volatiles emitted from P. pinea, P. sylvestris, and P. nigra foliage were sampled by solid-phase microextraction (SPME). Analysis of these volatiles by coupled gaschromatography/mass spectrometry revealed that the relative amounts of the compounds emitted by the three species were significantly different. A discriminant analysis showed that the amounts of limonene and myrcene significantly contributed to the species-specific volatile patterns. Pinus pinea emitted higher relative amounts of limonene than the other pine species. Pinus sylvestris emitted the highest relative amounts of myrcene. When testing the response of N. sertifer females to these pine terpenoids in an olfactometer bioassay, a low amount of limonene was attractive, while a repellent effect was evident when higher amounts were used. The sawfly females showed no significant olfactory response to myrcene. These data suggest that low relative amounts of limonene have a significant function in attracting N. sertifer females, while high amounts might contribute to avoidance of a tree.

Comparative analysis of monoterpene composition in four pine species with regard to suitability for needle consumer Diprion pini L

“…The presence of a relatively high content of these monoterpenes in P. strobus was noted by other authors as well (Bridgen et al, 1979;Klepzig et al, 1996). A comparative analysis of monoterpene composition in the needles of P. sylvestris, P. nigra and P. pinea demostrated that the main monoterpenes distinguishing these species were limonene and myrcene (Martini et al, 2010). According to our data, not only limonene and myrcene, but also relative amounts of β-pinene made a reliable difference between the needles of 4 investigated pine species (Fig.…”

Volatile Profile Differences and the Associated Sirex noctilio Activity in Two Host Tree Species in the Northeastern United States

“…In a comparative study of preferred (P. sylvestris and P. nigra) and non-preferred (P. pinea) host species of the pine sawfly, Neodiprion sertifer, the monoterpene limonene induced avoidance when present in higher relative amounts (Martini et al 2010). In S. noctilio, the oxygenated monoterpene components of P. radiata resin are thought to be repellents, or compounds that mask the attractiveness of the monoterpene hydrocarbons (Taylor 1981), although never tested in a bioassay.…”

“…It is likely that we missed volatile components relevant to the host-seeking behavior of S. noctilio. Although solvent-free methods such as thermodesorption (Helsper et al 2006) or collection on solid-phase microextraction (SPME) fibers (Martini et al 2010) provide only one-time analysis, they are useful techniques in the exploration of volatile chemical cues. Testing compounds more abundant in the volatile profile of attractive pine species, such as δ-3-carene, thujene, sabinene, γ-terpinene, and terpinolene in high-carene Scots pine, with electrophysiological methods and in behavioral assays will be a focal point of our investigations in the future.…”

Both Volatiles and Cuticular Plant Compounds Determine Oviposition of the Willow Sawfly Nematus oligospilus on Leaves of Salix spp. (Salicaceae)

“…Orientation towards host plant volatiles has been established for a number of sawflies. In free feeding sawflies, attraction to volatile compounds including green leaf volatiles, terpenes, and isothiocyanates has been documented (Barker et al 2006;Martini et al 2010;Piesik et al 2008). Additionally, in the leaf-galling sawfly (Pontania proxima Lepeletier), host plant location by volatiles has been hypothesized (Kehl et al 2010).…”