Composition of essential oils isolated from three plant species and their molluscicidal activity against Theba pisana snails

The essential oils of three plant species grown in Saudi Arabia, Eucalyptus camaldulensis Dehnh. (Myrtaceae), Lavandula dentata L. (Labiatae) and Ruta chalepensis L. (Rutaceae), were isolated by steam distillation. The constituents of these oils were identified by GC-MS. The main compounds in these three oils were Eucalyptole, a-Pinene, I-terpinene, 4-terpineol, p-Menth-I -en-8-ol, 1H-cyclopropazulene,  decahyd, Dodecane and In E. camaldulensis; Camphor, Fenchone, Fenchol, Bomeol, cis-linaloxide and ß-Pinene, in L dentata and 2-Nonanone, 2-NonanoI, Camphor, 2Undecanone, Butylatedhydroxytoluene, 3,4-Methylenedioxybenzylacetone, in R. chalepensis. The isolated three oils were tested for their molluscicidal activity against the land snail, Theba pisana. The volatile oil of L dentata was the most effective one while that of E camaldulensis was the Feast effective oil with LD50 values of 238.2 and 658 pg/g body weight, respectively. The possible applications and uses of these volatile oils in the field of plant protection are discussed. Key words: Essential oils, volatile oils, Eucalyptus camaldulensis, Lavandula dentata, Ruta chalepensis, molluscicidal activity, Theba pisana.