A predatory mite as potential biological control agent of Diaphorina citri

Diaphorina citri Kuwayama (Hemiptera: Liviidae) is a vector of the bacteria that cause Huanglongbing, the fatal disease threatening citriculture worldwide. One of the most important management methods is the control of D. citri with pesticides, but their intensive use causes development of resistance and pollution. An alternative method is therefore necessary to manage this vector-pathogen system. The generalist predatory mite Amblyseius herbicolus Chant (Acari: Phytoseiidae) can be found on citrus and orange jasmine plants, important hosts of D. citri in Brazil. Here we show that this phytoseiid can reproduce and develop on D. citri eggs. The predation rate was higher on D. citri eggs collected from plants in the field than on eggs from small plants from a laboratory rearing. Yet the predator preferred eggs from the laboratory. This may indicate that the higher predation rate of eggs from the field served to compensate for these eggs being of lower nutritional quality. This was confirmed with a series of experiments with limited numbers of eggs. We conclude that Amblyseius herbicolus is a potential biological control agent of D. citri, and its performance and control may be affected by the quality of the host plant.