CONICET | Buscador de Institutos y Recursos Humanos

Information on the chemical weed control in lily bulb production in South America is scarce. Greenhouse and field studies were conducted to evaluate the phytotoxic effect and weed control of pre- and postemergence herbicides in lily bulb production in Argentina. In greenhouse studies, bromoxynil, 415.2 g ai/ha; fluroxypyr, 200 g ai/ha; metsulfuron, 3 g ai/ha; iodosulfuron-methyl-sodium, 3 g ai/ha + metsulfuron, 3 g ai/ha; oxyfluorfen, 240 g ai/ha; ioxynil, 528.75 g ai/ha; and linuron, 750 g ai/ha produced severe phytotoxicity and/or death of bulbs. Glyphosate 720 g ai/ha and aclonifen 720 g ai/ha produced little to no symptoms and were considered safe to lily. In field conditions, pre-emergence herbicides metolachlor, 960 g ai/ha + atrazine, 1500 g ai/ha and metolachlor, 960 g ai/ha + flumetsulam 80 g ai/ha provided good weed control but were phytotoxic for lily plants with chlorosis as the main symptom. Metolachlor plus linuron resulted in little or no visual symptoms and no reduction in bulb yield. Diuron, 800 g ai/ha at postemergence was the most effective treatment without phytotoxicity, and in combination with metolachlor, 960 g ai/ha + linuron, 750 g ai/ha at pre-emergence controlled weeds until 40 days after diuron application, without yield reduction. Results obtained with glyphosate indicate that the Lilium genus presents some tolerance to this herbicide, which justifies further evaluation for weed control in lily bulb production.