Ocimene

Ocimene is a monoterpene found in a variety of plants, including Cannabis, and is a volatile compound involved in plant-plant signaling and plant defense against pests. Emission of ocimene from tea (C. sinensis) and L. japonicus plants is induced in response to a jasmonic acid combined with mechanical damage (JAMD) model of herbivore attack and within 24 hours of spider mite (T. urticae) infestation, respectively. Ocimene reduces the number of winged aphids (M. persicae) that settle on Chinese cabbage and the feeding time and number of nymphs produced by aphids on leaves. The aphid endoparasitoid A. gifuensis demonstrates a preference for ocimene-treated Chinese cabbage over control plants in a wind tube two-choice test. Conditioning of tomato plants using volatile organic compounds (VOCs) from transgenic tobacco plants overexpressing β-ocimene synthase increases production of VOCs and reduces the number of aphids (M. euphorbiae) that settle on the plant and the number of nymphs produced by the aphids that settle, as well as increases the number of landings of the aphid parasitoid A. ervi compared with conditioning using wild-type tobacco VOCs. Formulations containing ocimene have been used as fragrance ingredients.