Systemic insecticides for control of Citrus mealybug in gardenias.
Planococcus citri (Risso) is a serious pest attacking greenhouse crops, and in California various biological and chemical methods of control have been tried. In 1972, in a greenhouse, the systemic insecticides dimethoate and oxydemeton-methyl as emulsifiable concentrates at 2 lb/US gal and aldicarb as 10% granules were applied for control of this mealybug on gardenia in January, being watered into the soil with a drench of 2500 ml water/plant. Infested terminal shoots were counted in February, April, May and June. Aldicarb gave the best control, but, since it remained effective for only half the growing season, two applications are recommended. Dimethoate remained effective for three months, and oxydemeton-methyl was not much more effective than no treatment. None of the insecticides appeared to injure the plants.<new para>ADDITIONAL ABSTRACT:<new para>Cygon (dimethoate) and Meta-Systox-R (oxydemeton methyl), each at 2 lb/gal applied as soil drenches, were compared with Temik (aldicarb) 10% granular concentrate, applied dry and immediately watered in, for the control of Planococcus citri on gardenias in 5-gal containers. Temik gave complete control for 4 months and moderate control for 5 months. Cygon gave good control for 3 months, but Meta-Systox-R was ineffective. No phytotoxicity was caused by any of the treatments.