Efficacy of extracts of saponin containing plants against Pulvinaria psidii (Scale insects)

Lethal concentrations (LC₅₀) of saponin-containing plant extracts against the scale insect Pulvinaria psidii were determined. The methanol extracts were derived from Yucca aloifolia L., Glycine max (L.) Merr., Sapindus mukorossi Trigonella foenum-graecum L., Linum usitatissimum L., and Acacia concinna (Willd.) DC. Those were diluted to 0.5, 1.0, 1.5, and 2.0 % concentrations and used for bioassay, conducted by leaf dip method. The observations were recorded after 24-, 48-, and 72-hours post-exposure. Among the plant extracts, Yucca aloifolia demonstrated highest insecticidal potential exhibiting lowest LC₅₀ values against Maccolinicocus hirsutus.