Evaluation of petroleum spray oils for control of the Asian citrus psylla, Diaphorina citri (Kuwayama) (Hemiptera: Psyllidae), in China

Abstract

The efficacy of petroleum spray oil against citrus psylla was tested in Guangzhou, China. As the oil concentration increased from 0.25% to 1.0% there was a linear decrease in the number of psylla of each stage present on foliar shoots after 8 days. When psylla infested shoots were sprayed with equivalent oil concentrations, survival was significantly different between oil treatments. Psylla survival was also stage-dependent, with 1st- 2nd instars being the most susceptible and eggs being the most tolerant to oil. Oil efficacy was compared to an organophosphate pesticide and an insect growth regulator, and all provided similarly effective controlofpsylla nymphs. Controlofeggs was not achieved by any of the treatments as application of sprays was not correctly timed. Keywords: Diaphorina CitriPetroleum OilCitrus Greening Disease