Avaliação da ecotoxicidade de microrganismos eficientes para organismos edáficos em solo artificial

Abstract

The use of soil is a global concern, and its maintenance and/or improvement are crucial to ensure food security and biodiversity. Its utilization has been intensified through technologies such as the use of efficient microorganisms (EMs). In this context, predicting the impact of EM usage on non-target soil organisms becomes a necessary measure. The objective of this study is to evaluate, based on standardized ecotoxicological tests, whether the application of efficient microorganisms (EMs) from a commercial formulation and those produced in On-Farm bioreactors affect the survival and reproduction of earthworms (Eisenia andrei) and springtails (Folsomia candida). Standardized assays were conducted to measure the effects on the survival and reproduction of Eisenia andrei earthworms and Folsomia candida springtails. For the assays, Tropical Artificial Soil (TAS) was used, with pH adjusted to 6.0 ± 0.5. Each species was exposed to increasing doses of EMs obtained commercially and those produced On-Farm, evaluating 0 (control with distilled water); 50%; 100%; 200%; and 400% of the manufacturer's recommended dose. Lethality and reproduction assays with both species were conducted at a temperature of 20°C (± 2°C) and a photoperiod of 12 hours. The results were subjected to analysis of variance (One-way ANOVA) and, if a statistical difference was found, compared using Dunnett's test (p < 0.05). The lethality and reproduction tests met the validation criteria established by the International Organization for Standardization (ISO) 11268-2 for earthworms and ISO 11267 for springtails. The results show that increasing doses of EMs from both tested inoculants did not affect the lethality and reproduction of earthworms and springtails. These findings indicate that EM applications, even at high concentrations (4x the recommended dose), do not affect the tested soil organisms. Doses ranging from 25% to 400% of the recommended application rates for both commercially produced and On-Farm EMs do not affect the lethality and reproduction of earthworms and springtails.