To assess the biological activity of origanum majorana essential oils and salvia officinalis, 6 concentrations were tested as fumigation against Bruchus lentis (Coleoptera, Chrysomelidae) high on lentil seeds. Essential oils from two plants affect biological parameters weevil. The main components are marjoram: Trans Sabinene hydrate (26,64%), Terpinen-4-ol (17,08%) and o-Cymene (6,29%), while those of sage are: α-Thujone (20,52%), Eucalyptol (12,39%) and γ-Gurjunene (11,13%). The survival time of 50% of adults exposed to different concentrations of essential oils ranges from less than 24 hours to about 4 days depending on the concentration, while in the control group, in live adult average of 7 to 11 days. After 48h the letal concentration LC50 fumigation marjoram is 10,28μl/ l while that of the sage is 13,42μl/l. The intensity of the impact of the essential oil is directly dependent on their concentrations. The essential oils of officinal sage and marjoram studied can be integrated into management weevils, stored and associated with the pulses thus replace the phosphine and methyl bromide.
Keywords: Bruchus lentis, Chemical composition., Fumigants, LC50, LT50, Origanum majorana, Salvia officinalis
