Response of Sugarbeets (Beta vulgaris) and Four Weed Species to Dinitramine

Dinitramine (N 4,N 4-diethyl-α,α,α-trifluoro-3,5-dinitrotoluene-2,4-diamine) applied at 0.37 kg/ha controlled black nightshade (Solanum nigrum L.) better than did trifluralin (α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine) at 0.56 kg/ha. Dinitramine applied at 0.37 kg/ha was equal to 0.56 kg/ha of trifluralin for control of green foxtail [Setaria viridis (L.) Beauv.], yellow foxtail [Setaria glauca (L.) Beauv.], and redroot pigweed (Amaranthus retroflexus L.). Dinitramine produced more root aberrations in sugarbeets (Beta vulgaris L. ‘Mono Hy D2′) than did trifluralin when sprayed on nonexposed or exposed hypotcotyledonary tissues of seedlings. When soil surrounded most of the hypocotyls at the time of application, 0.56 kg/ha of dinitramine affected 57 to 87% of the roots, whereas the same rate of trifluralin affected 1 to 8% of the roots. When the hypocotyls were exposed at the time of application, 100% of the roots were affected by dinitramine compared to 25% of all roots treated with trifluralin. Dinitramine applied at 0.37, 0.42, and 0.56 kg/ha lowered the quality and yield of sugarbeet roots, with the highest rate significantly reducing percentage purity, percentage sucrose, and recoverable sucrose. Trifluralin did not affect these parameters.