Efecto del glifosato en la morfologia del tubo dogestivo y en la actividad acetilcolinesterasa de la lombriz Eisenia fetida

Abstract

[EUS] Gaur egun produktu kimiko ugari erabiltzen dira nekazaritzaren produktibitatea emendatzeko eta modu honetan nekazaritza-produktuen etekin eta kalitatea hobetzeko asmoz. Hala ere, produktu kimiko hauek ekosisteman izan ditzaketen hilgarriak ez diren eraginak askotan ez dira kontuan hartzen. Azken urteotan osagai aktibo gisa glifosatoa duten herbiziden erabilera emendatu da. Lan honetan, glifosatoak ingurunean sor ditzakeen eraginak ikertu nahi izan dira, lurzoruan oso ugaria den Eisenia fetida zizarea adierazle biologiko gisa erabiliz. Esperimentuan 10 indibiduo helduz osaturiko 4 populazio erabili ziren, zeinak 14 egunez tratamendu desberdinetan ezarri ziren (kontrola, 50, 500 eta 5000 mg glifosato/Kg lur lehor). Glifosato kontzentrazio desberdinek ez zuten zizareen hilkortasunean edo pisuaren aldaketan eraginik izan. Hala ere, digestio-hodiaren epitelioaren morfologian eta azetilkolinesterasaren jardueran aldaketak behatu ziren. Glifosato kontzentrazio baxueneko ontziko zizareetan digestio-hodiko epitelioaren altueraren uniformetasun falta behatu zen, glifosato kontzentrazio ertaineko ontziko zizareetan orokorrean epitelioaren altuera txikiagoa zen, eta glifosato kontzentrazio handieneko ontziko zizareetan digestio-hodien borobiltasuna eta epitelioaren jarraitasuna galdu zen. Azetilkolinesterasaren jardueraren murrizpena behatu zen glifosatodun lurretan egondako zizareetan. Esperimentu honetan erabilitako glifosato kontzentrazioek zizareengan hilgarriak ez diren aldaketak sortzen dituzte, aztertutako biomarkatzaileak etorkizuneko ekotoxikologia testetan erabilgarriak izan daitezkeelarik.

[EN] Today, a lot of chemicals are used in agriculture to increase productivity and in this way improve the quality of agricultural products. However, the sublethal effects that could have these chemicals on the ecosystem usually are not taken into account. In recent years, the uses of herbicides containing glyphosate as the active ingredient are increasing. This paper aims to investigate the effects of glyphosate using the earthworm Eisenia fetida, which is very abundant in soils, as a biological indicator. 4 populations of 10 adults were used in this experiment, which were exposed to different treatment for 14 days (control, 50, 500, 5000 mg glyphosate/Kg dry soil). Different concentrations of glyphosate did not have any impact on mortality or weight change on the worms. However, changes in the digestive tract epithelium morphology and cetylcholinesterase activity were observed. In the worms exposed to the lowest glyphosate concentration soil was observed lack of uniformity in the height of the digestive tract epithelium, in the worms exposed to medium glyphosate concentration soil the height of the digestive tract epithelium was generally lower, and in the worms exposed to the highest glyphosate concentration soil was observed lack of roundness and continuity of digestive tract epithelium. Reduction of acetylcholinesterase activity was observed in the worms that were exposed to soils with glyphosate. Glyphosate concentrations used in this experiment have sublethal effects in the worms, making useful the analyzed biomarkers in future ecotoxicological tests.