Evaluation of petroleum based horticulture oil for the management of the tea red spider mite, Oligonychus coffeae Neitner (Acarina: Tetranychidae)

Abstract

The Servo agro spray oil (petroleum based horticulture oil) was evaluated in the laboratory against tea red spider mite, Oligonychus coffeae to determine its effect on adult mortality, viability of eggs, oviposition deterrence and repellent properties. The same was also evaluated in the field to determine its effect on mite population. Direct spray method was used in the laboratory at concentrations of 0.5, 1.0, and 1.5%. Mortality of O. coffeae was both concentration and time dependent. Deposition of eggs by adult mites on treated leaf surfaces decreased significantly and the viability of eggs was also significantly reduced. In addition, different concentrations of the Servo agro spray also exhibited repellent properties against adult mites. In the field Servo agro spray oil significantly reduced the mite population and its bio-efficacy was comparable to that of the synthetic pesticide (propargite 57 EC). No phytotoxic effect was observed when tea bushes were sprayed with different doses of Servo agro spray. Tea samples were taint free. Quality (appearance of liquor, flavour, taint and taste) of made tea was not adversely affected by treatments with Servo agro spray oil. Therefore Servo agro spray oil may be a potential agent to be used in the sustainable management of tea red spider mite.