Essential oils of three species of scutellaria and their influence on Spodoptera littoralis

The recent literature about the essential oils of different species of Scutellaria have been reviewed (Skaltsa et al., 2000, 2005; Rosselli et al. (2007); Formisano et al. (2011). As far as we know, there is no report on the chemical composition of S. brevibracteata. Recently Raccuglia et al. (2010) isolated seven neo-clerodane diterpenoids from S. hastifolia, three of which showed significant antifeedant activity against Spodoptera littoralis. No studies have been carried out on the volatile constituents of the aerial parts of these two species, while the essential oil of S. orientalis ssp. alpina has been described (Formisano et al., 2011). Recently, the chemical composition of the essential oil of Scutellaria rubicunda Hornem. ssp. linnaeana (Caruel) Rech. has been reported, along with its effect on the feeding and egg laying behaviour of S. littoralis (Rosselli et al., 2007). As a continuation of our studies on species of Scutellaria (Bruno et al., 1996, 1998; Raccuglia et al., 2010), we describe the volatile compounds in the essential oils of S. brevibracteata, S. Hastifolia and S. orientalis ssp. alpina as well as their activity against the feeding and egg laying behaviour of S. littoralis.