Earthworms to assess the innocuousness of spent biomixtures employed for glyphosate degradation

MASIN, CAROLINA E.; LESCANO, MAIA R.; RODRÍGUEZ, ALBA R.; GODOY, JOSÉ L.; ZALAZAR, CRISTINA S.

JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART B - PESTICIDES, FOOD CONTAMINANTS, AND AGRICULTURAL WASTES

TAYLOR & FRANCIS INC

Año: 2018 p. 1 - 7

0360-1234

In thisstudy, the innocuousness of different biomixtures employed for glyphosatedegradation was tested through Eisenia fetida earthworms. Eight biomixtureswere prepared with local materials: alfalfa straw (AS), wheat stubble (WS),river waste (RW) and two different soils (A and B). Each biomixture was dividedinto two equal portions: one without glyphosate application (control substrate)and the other was sprayed with a commercial glyphosate formulation of 1000 mgglyphosate a.i. per kg of biomixture (applied substrate). The bioassay started whenall sprayed biomixtures reached high percentages of glyphosate degradation (spentbiomixtures). Three parameters were studied: survival, adults and juvenilesbiomass and reproduction. The results allowed the identification of threebiomixtures (AWS, BWS and BWSRW) for good maintenance and development of E. Fetida.In addition, at the end of the bioassay two of the viable biomixtures (AWS andBWS) showed the highest performance of juvenile earthworms compared to a referencesoil. The Principal Component Analysis (PCA) indicated that the biomixturescontaining high silt and clay percentages and minor density renders highervalues of earthworm growth and reproduction. Therefore, these innocuousbiomixtures can be used as organic amendments or recycled materials for newtreatments on biobeds.