Temperature and Aging Affect Glyphosate Toxicity and Fatty Acid Composition in Allonychiurus kimi (Lee) (Collembola)

Abstract

Glyphosate is the most used herbicide worldwide, but enormous use of glyphosate has raised concerned about its environmental loadings. Although glyphosate is considered non-toxic, toxicity data for soil non-target organisms according to temperature and aging are scarce. This study examined the toxicity of glyphosate with the temperature (20 °C and 25 °C) and aging times (0 day and 7 days) in soil using a collembolan species, Allonychiurus kimi (Lee). The degradation of glyphosate was investigated. Fatty acid composition of A. kimi was also investigated. The half-life of glyphosate was 2.38 days at 20 °C and 1.69 days at 25 °C. At 20 °C with 0 day of aging, the EC50 was estimated to be 93.5 mg kg−1. However, as the temperature and aging time increased, the glyphosate degradation increased, so no significant toxicity was observed on juvenile production. The proportions of the arachidonic acid and stearic acid decreased and increased with the glyphosate treatment, respectively, even at 37.1 mg kg−1, at which no significant effects on juvenile production were observed. Our results showed that the changes in the glyphosate toxicity with temperature and aging time were mostly dependent on the soil residual concentration. Furthermore, the changes in the fatty acid compositions suggest that glyphosate could have a chronic effect on soil organisms.

Species‐specific environmental DNA analysis of the index species in soil ecosystem,Allonychiurus kimi(Collembola: Onychiuridae)

“…For example, the compressed soil test allows continuous monitoring of molting, number of eggs and hatchability without pretreatment during exposure periods because on the compressed soil collembolans cannot burrow in the soil (Lee, Son et al, 2019 ). Moreover, some studies suggested more sensitive biomarkers using regulating patterns of protein, composition of fatty acid, and gene expression (Lee et al, 2018 ; Nota et al, 2008 ; Wee, Lee, Kim, Son, et al, 2021 ). Although these alternative approaches and biomarkers overcome the limitations of the existing methods, it is still a laborious procedure to obtain the results.…”

“…Then, this collembolan population has been maintained at the Ecology & Toxicology Laboratory, Korea University, Seoul, South Korea (accession number KUETCOLC001) for approximately 25 years (Lee, Lee et al, 2021 ). The A. kimi colony was maintained in a plastic Petri dish (90 mm × 15 mm (diameter × height) (D × H)) filled with 0.5 cm deep substrate comprise of plaster of Paris, activated charcoal, and distilled water at a ratio of 4:1:4 by volume at 20 ± 1°C with continuous darkness (Wee, Lee, Kim, Son et al, 2021 ). Distilled water was added periodically, and the plastic Petri dishes were aerated weekly to maintain the fresh condition of the substrate.…”

“…Allonychiurus kimi (Lee, 1973) (Collembola: Onychiuridae) is the dominant collembolan species in the paddy fields of Korea. The influences of temperature, humidity, and nutrition on life table statistics were investigated (Choi et al, 2002 ), and many ecotoxicology studies were conducted for evaluating ecotoxicity of heavy metals, pesticides, and herbicides (Choi et al, 2008 ; Son et al, 2007 , 2016 ; Wee, Lee, Kim, Lee, et al, 2021 ; Wee, Lee, Kim, Son, et al, 2021 ). In addition, recently, the complete mitochondrial genome of A. kimi was reported (Lee, Lee, et al, 2021 ).…”

Recent Advances in Stimulus-Responsive Nanocarriers for Pesticide Delivery

“…Temperature-responsive polymeric materials are substances that exhibit changes in their physical or chemical properties in response to variations in the external temperature. , The most representative property of such materials is LCST; when the homogeneous polymer starts phase separation at a high temperature, the lowest temperature of the phase separation curve on the concentration–temperature diagram is considered the critical solution temperature. Specific temperature-sensitive polymeric materials experience reduced solubility, leading to precipitation or phase separation.…”