TOXICITY OF PESTICIDES USED IN CITRUS TO APROSTOCETUS VAQUITARUM (HYMENOPTERA: EULOPHIDAE), AN EGG PARASITOID OF DIAPREPES ABBREVIATUS (COLEOPTERA: CURCULIONIDAE)

Abstract

Twelve pesticides used in citrus were tested for their contact toxicity to Aprostocetus vaquitarum Wolcott (Hymenoptera: Eulophidae) a parasitoid of Diaprepes abbreviatus (L.) (Coleoptera: Curculionidae). Sevin® 80 WSP, Malathion 5 EC, and Imidan® 70 WSB resulted in the most rapid death of A. vaquitarum adults. Admire® 2F, Danitol® 2.4EC, and Surround® WP were also very detrimental. Kocide® 101 WP, Citrus Soluble Oil, Micromite® 80 WGS, Acramite® 50 WS, Micromite® 80 WGS Citrus Soluble Oil, Aliette WDG, and Agrimek® 0.15 EC Citrus Soluble Oil were slightly to non-toxic to A. vaquitarum. The relative toxicity of the pesticides was consistent up to four weeks after application. Significantly fewer adult A. vaquitarum emerged from D. abbreviatus eggs laid on foliage treated in the field with Sevin® XLR and Imidan® 70 WSB than emerged from the water treated control. Field residues of Sevin® XLR remained toxic for seven days while the effects of Imidan® 70 WSB were no longer significant after one week. The number of A. vaquitarum adults emerging from host eggs laid on treated foliage was not significantly different among Micromite® 80 WGS, Acramite® 50 WS, and the control, but significantly fewer adults emerged from foliage treated with either Micromite® 80 WGS Citrus Soluble Oil or Citrus Soluble Oil alone. There were no significant differences between oviposition or new generation adults when A. vaquitarum was exposed to Micromite® 80 WGS or a water control.