Toxic effects of some inert dusts on Agonoscena pistaciae (Psyllidae: Hemiptera)

Abstract

Pistachio psyllid Agonoscena pistaciae Burckhardt and Lauterer (Hemiptera: Psyllidae) has emerged as a significant pest of pistachio in recent years. This pest feeds on pistachio trees (Pistacia vera) from the Anacardiaceae family during its nymph and adult stages, leading to a reduction in both the quality and quantity of the product. Although various insecticides belonging to different groups have been used to control this pest, alternative control methods are needed due to concerns over the environmental impact of insecticides and residue issues. In this study, the toxic effects of inert dusts (diatomite, kaolin, sepiolite, borax, halloysite, and zeolite) obtained from Türkiye were investigated against the pistachio psyllid. The inert dusts at the concentration of 7.5% (w/v) were applied to third-instar nymphs by using a hand sprayer. The mortality results were recorded at 24-hour intervals for 144 hours. Among the tested inert dusts, kaolin and diatomite (Detech® 95 WP) caused mortality in the nymphs, while no mortality was observed with the other inert dusts throughout the incubation period. Detech® 95 caused 95% mortality in the first 24 hours, and the mortality rate increased to 100% by the end of the 48-hour incubation period. While no mortality was observed with kaolin treatment in the first 48 hours, 7% mortality rate was recorded at 72 hours and this increased to 10% at 96 hours. This study showed that the commercial formulation Detech® 95 WP, containing diatomite, has potential for use in controlling pistachio psyllid nymphs.