Based on CL50, the essential oil of
lemongrass was 5.3 times more toxic to M. persicae
than F. schultzei (Table 2). The CL90 of this
essential oil on M. persicae was estimated at 0.85%.
The inclination of the concentration-response curve
of the essential oil of lemongrass on M. persicae
was greater than on F. schultzei (Table 2). The
upper value of inclination of the concentrationresponse
curve indicated that a slight variation in the
concentration of the essential oil caused a large
variation in mortality. In the control with F.
schultzei, mortality was 7.0 ± 2.61%
(mean±standard-error), and in the control with M.
persicae, mortality was 6.6 ± 1.71%.