Biological activity of Essential oil of sage plan leaves Salvia offecinalis l. against the black cutworm Agrotis ipsilon (Hubn.)

The black cutworm, Agrotis. ipsilon (Lepidoptera: Noctuidae)is one of the most destructive insect pest attacking different field crops. Biological activity of Sage plant leaves essential oil was evaluated against 2^nd instar larvae of A. ipsilon.  Bioassay test showed that 4% Sage  plant oil  (Salvia officinalis) induced 96%, 63.6% starvation and antifeeding activity respectively, 75% of larval mortality recorded after 8 days of treatment, then all larvae died at the10^th day. The mortality percentage, starvation and antifeedant activity were positive concentration dependent. The oil disrupts the hormonal balance in the larvae when ingested with treated diet contained sub lethal concentration (LC₅₀ = 1.806%) which could be calculated after 8 days form larval treatment), producing malformed pupae which failed to give rise to adults, or developed into intermediate larval-pupal forms. The adult abnormalities failed to expand their wings and to emerge from the puparium. At the sub lethal concentration , the essential oil gave a relatively high percent of reduction  (67.4% in egg deposition and 69.4%% in egg hatchability and caused above 31.2%% sterility among the resulting females. The survived larvae completed their life cycle with retarded growth. This was accompanied with reduction in larval weight, pupal weigh, adult emergence and fecundity, increasing percentage of deformities and prolongation of the larval period. Pupation percentage decreased with 58% and in moths emergence with 24% . From this point of view, and so could be recommending usage of the sage plant leaves essential oil for  controlling the black cutworm on their hosts by spraying it as emulsion on their host plants  or as a toxic baits alternatives to chemical pesticides and decreasing the insect resistant buildup as a biological control method throughout the integrated pest control program.  Present results showed that the essential oil from Sage plant leaves is potentially useful for management A.ipsilon insects population.