Postemergence Herbicides for Crop Safety and Weed Control in Pearl Millet Hybrids

Greenhouse and field experiments were conducted at Hays, KS, to test various POST herbicides for crop safety and weed control in pearl millet. Five pearl millet hybrids (Hyb1 to Hyb5) in the greenhouse and three hybrids (Hyb1, Hyb-2k, Hyb-3k) in field experiments (site 1 and 2) were evaluated. All herbicides were safe (1 to 5% injury) on all pearl millet hybrids in the greenhouse and field experiments at 28 days after application (DAA), except imazamox and nicosulfuron (22 to 35% injury). At site 1, 2,4-D, dicamba, bromoxynil + pyrasulfotole, 2,4-D + bromoxynil + fluroxypyr, and dicamba + 2,4-D effectively controlled Palmer amaranth (88 to 91%) and reduced density (2 to 4 plants m -2 ) compared to nontreated (18 plants m -2 ) at 42 DAA. The least control (60 to 65%) and greater density (8 plants m -2 ) of Palmer amaranth was observed with imazamox and nicosulfuron. In contrast, imazamox and nicosulfuron effectively controlled (91 to 92%) and reduced the density (2 plants m -2 ) of green foxtail compared to nontreated (13 plants m -2 ) at 42 DAA. No weed emergence was observed at site 2 across all treatments (including nontreated); therefore, weed control was not reported. Across both sites, 2,4-D + bromoxynil + fluroxypyr resulted in the highest grain yield of Hyb1 (3,866 to 4,619 kg ha -1 ), Hyb-2k (2,222 to 3,699 kg ha -1 ), and Hyb-3k (822 to 1,315 kg ha -1 ). These results highlight that the POST herbicides tested in this study, except imazamox and nicosulfuron can be safely used for weed control in pearl millet.