Glyphosate sprayed on the pre-existing vegetation reduces seedling recruitment and growth of forage species

A. RODRIGUEZ; JACOBO, E; GRIMOLDI, A.A.; GOLLUSCIO R.A

REVISTA DE LA FACULTAD DE CIENCIAS AGRARIAS DE LA UNIVERSIDAD NACIONAL DE CUYO

UNIV NACIONAL CUYO

Lugar: Mendoza; Año: 2022 vol. 54 p. 35 - 45

0370-4661

Seeding pastures or forage crops by no-tillage methods usually involves the spray ofglyphosate to suppress the existing vegetation. While many studies found detrimentaleffects of glyphosate on seed germination and seedling growth of the subsequent crop,others found negligible effects. This study aimed to evaluate the effect of glyphosatespraying on germination, seedling emergence and seedling growth of four forage species:Trifolium repens, Lotus tenuis, Festuca arundinacea and Paspalum dilatatum. The experimentwas carried out spraying glyphosate on the pre-existing vegetation and on bare soil 1, 30, 60and 90 days before sowing, and a control treatment sprayed with water. Glyphosate sprayedon pre-existing vegetation 1 to 60 days before seeding reduced emergence, while sprayed1 to 30 or 1 to 60 days before seeding reduced seedlings belowground biomass and rootlength of all species and aboveground biomass of legumes respect to sprayed 90 days beforeseeding, sprayed on bare soil, and control treatment. This herbicide would remain active inthe soil environment for at least 60 days after spraying when it was previously absorbed byplants, causing a severe damage to seedlings emergence and growth.