Yellow nutsedge (Cyperus esculentus) control with metham-sodium in transplanted cantaloupe (Cucumis melo)

Irrigated field trials were conducted from 2001 to 2003 in Tifton, Georgia at the Coastal Plain Experiment Station to determine the optimum combination of pre-plant fumigation interval, metham-sodium dose, and seedbed mulching for yellow nutsedge control in transplanted cantaloupe. The trial evaluated all possible combinations of pre-plant fumigation intervals (1-wk, 2-wk, or 3-wk before transplanting), three metham-sodium doses (nontreated, 374, and 748 l/ha), and seedbed mulching (bareground or black polyethylene mulched seedbeds). Metham-sodium sprayed and soil incorporated at 374 and 748 l/ha effectively controlled yellow nutsedge when seedbeds were covered by black polyethylene mulch, with minimal fumigant phytotoxicity. In contrast, yellow nutsedge control from metham-sodium was reduced when seedbeds were not mulched. Cantaloupe treated either 1-wk or 2-wk before transplanting with metham-sodium at 748 l/ha yielded greater than other treatment combinations. Black polyethylene mulch increased cantaloupe yield when averaged across all possible combinations of pre-plant fumigation intervals and metham-sodium doses, due primarily to improved yellow nutsedge control over bareground seedbeds.