Composition of Pistacia khinjuk (Anacardiaceae) Leaf Essential Oil and its Insecticidal Activity on Common Pistachio Psyllid, Agonoscena pistaciae (Hem., Psylloidea)

Abstract

Wild pistachio species, Pistacia khinjuk Stocks, is the non-preferred host plant of common psyllid, Aganoscena pistaciae, the key pest of cultivated pistachios, P. vera L. in many Asian countries. P. khinjuk essential oil (EO) was obtained from leaf samples via hydro-distillation. EO chemical composition was identified by GC and GC-MASS. Forty compounds out of 48 total compounds were identified in oil. The major constituents of EO were myrcene (18.7 %), α-eudesmol (12.3 %), β-eudesmol (9.3 %), 1,7-di-epi-β-cedrene (7.3 %), bicyclogermacrene (5.6 %) and δ-eudesmol (4.9 %). Insecticidal activity of EO and pure myrcene, as the major EO constituent, were separately determined through contact bioassay tests against the psyllid eggs and nymphs. Both EO and myrcene caused approximately equal mortalities of 30-45 % on eggs and 65-90 % on nymphs. This is the first report about the insecticidal activity of P. khinjuk essential oil against A. pistaciae.