Journal of Pest Science (2022) 95, 1121-1133

Matheus Rakes, Rafael Antonio Pasini, Maíra Chagas Morais, Renato Zanella, Osmar Damian Prestes, Daniel Bernardi and Anderson Dionei Grützmacher (2022)
Residual effects and foliar persistence of pesticides used in irrigated rice on the parasitoid Telenomus podisi (Hymenoptera: Platygastridae)
Journal of Pest Science 95 (3), 1121-1133
Abstract: We evaluated the lethal and sublethal effects of azoxystrobin, cyhalofop-butyl, and thiamethoxam on Telenomus podisi after spraying rice plants in a greenhouse, as well as the degradation kinetics of these compounds over time. Pesticides were sprayed at 50 and 100% of the maximum field recommended concentration for the crop (MFRC). At 0, 5, 10, and 20 days after application of the treatments (DAAT), T. podisi was exposed to leaves containing dry pesticide residues. On these same dates, rice leaves from each treatment were collected for determination of pesticide residues by UHPLC–MS/MS. Based on the results for mortality, parasitism, emergence, and sex ratio of T. podisi, the effects were grouped using a reduction coefficient (E_x) and classified according to the scale of the International Organization for Biological and Integrated Control (IOBC). The fungicide azoxystrobin (at 50 and 100% MFRC) was the only one classified as harmless (Class 1). The herbicide cyhalofop-butyl was classified as slightly harmful (Class 2) to T. podisi until 5 DAAT. The insecticide thiamethoxam (50 and 100% MFRC), up to 5 DAAT, was classified as harmful (Class 4) on T. podisi. Regarding residue, the initial concentrations (0 DAAT) of azoxystrobin, cyhalofop-butyl, and thiamethoxam at 100% MFRC in rice leaves were 102.14, 210.09, and 36.93 mg kg^-1, respectively. At 50% MFRC, initial waste was approximately half that extracted at 100% MFRC. The estimated half-lives (DT₅₀) were approximately 17, 4, and 5 days for azoxystrobin, cyhalofop-butyl, and thiamethoxam, respectively. Furthermore, we found a positive correlation between effects and residues.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Anderson Dionei Grützmacher

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
resistance to pesticides

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
Telenomus podisi (parasitoid)			Brazil (south)