Toxicity of pesticides to Tamarixia radiata, a parasitoid of the Asian citrus psyllid

Abstract

Sixteen pesticides including two fungi- cides were evaluated for toxicity to adult Tamarixia radiata (Waterston) (Hymenoptera: Eulophidae), a parasitoid of the Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae). Percentage mor- tality data were evaluated to generally assess IPM- compatibility of the pesticides with adult parasitoids. The following were found to be least compatible with (most toxic to) adult T. radiata based on the toxicity of direct sprays and potential long residual life on leaves: carbaryl, chlorpyrifos, and fenpropathrin. Although highly toxic to the parasitoid as direct sprays or freshly dried residues, each of the following was more compatible with T. radiata because the toxicity of residues of these pesticides was either low at one to three days after application or relatively non-persis- tent: abamectin, chenopodium oil, fenpyroximate, and spirotetramat. Depending on environmental conditions, imidacloprid (foliar-applied), phosmet, pyridaben, sulfur and 435 spray oil might also be somewhat more compatible for the same reasons. The pesticides that consistently appeared to be most compatible with T. radiata were aluminum tris, copper hydroxide, diflubenzuron, and kaolin clay (Surround WP).