Determination of the toxic effects of diatomaceous earth and entomopathogenic fungi against the tomato leafminer moth, tuta absoluta (meyrick) [lepidoptera: Gelechiidae]

Abstract

This study was performed in the Department of Plant Protection, Bursa Uluda & gbreve; University, the tomato varieties Albeni and UG 12406 740 were provided by United Genetics Turkey Seedling Company. This study sought to determine the toxic effects of diatomaceous earth and entomopathogenic fungi against the tomato leafminer moth, Tuta absoluta, as an alternative to insecticides. Diatomaceous Earth (DE) was combined with Paecilomyces fumosoroseus strain PFs-1 (Priority) and Verticillium lecanii strain Bb-1 (Nibortem) to manage T. absoluta larvae, alongside a positive control of Azadirachtin (Nimbecidine) and an untreated control group. Laboratory investigations revealed that Nibortem+ DE and Priority+ DE exhibited the maximum efficacy, attaining a larval mortality rate of 96.6% and 93.3% within 96 hours. In field studies with the Albeni variety, optimal toxic effects (elevated mortality, minimal infestation) were seen with Nibortem + DE and Priority + DE combinations, which achieved high mortality rates of 93.3% and 92.3%, with infested fruit at 44.6% and 52.4%. In the UG 12406 740 variety, optimal toxic effects were seen with Nibortem + DE and Priority + DE combinations, which achieved high mortality rates of 88.8% and 77.7%, with infested fruit at 37.4% and 47.6%, respectively.