Proso Millet Date of Planting and Tolerance to Atrazine

Abstract

Proso millet (Panicum miliaceum L. ‘Turghai’, ‘M28’, and ‘Panhandle’) was planted at three or four dates from late April to late June in 1970, 1971, and 1972 on silt loam soil and in 1972 on sandy soil. A single spray application of 2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine (atrazine) at 2.24 kg/ha on half of each date plot was preemergence to the first date and preplanting to the last two or three dates of planting. Proso millet was not injured by atrazine. At each date, weed control was better on sprayed than on untreated plots. Foxtails (Setaria spp.) were the only weeds present after all plots on silt loam soil were sprayed postemergence with (2,4 dichlorophenoxy)acetic acid (2,4-D). Millet planted early produced higher yields than millet sown at normal planting dates if foxtail competition was not serious. Use of selective herbicides and spring planting offer a potential major gain in the profitability of millet production in areas where annual weed problems now relegate millet to summer planting.