Efficiency of sweet flag and curly parsley volatile oils compared with synthetic insecticides against Ceroplastes rusci on Ruellia plants

Summary Ruellia simplex plant is grown for its aesthetic features including flowers, leaves and overall foliage appearance. The fig wax scale Ceroplastes rusci L. (Hemiptera: Coccidae) was detected for the first time in Egypt on R. simplex. Mineral oil, diazinon, thiamethoxam + chlorantraniliprole, and essential oils extracted from Acorus calamus and Petroselinum crispum, were compared for their ability to control the insect. Results indicated that reduction percentage increased gradually until day 7 after the treatment regarding adults, nymphs and their total. The maximum efficacy of the mineral oil, and thiamethoxam + chlorantraniliprole, was noticed 21 days after treatment, followed by A. calamus oil. Efficacy of P. crispum oil and diazinon reached more than 86% after 21 days and more than 90% 28 days after treatment. At 28 days, A. calamus oil reached its maximum efficacy. Plants treated with thiamethoxam + chlorantraniliprole were the tallest plants and possessed significantly higher number of branches and leaves, and leaf pigments followed by those treated with mineral oil or A. calamus oil. A. calamus oil and thiamethoxam + chlorantraniliprole were proved as promising compounds tested for the first time in controlling C. rusci.