Aberrations in Sugarbeet Roots as Induced by Trifluralin

Abstract

Sixty percent of the roots of sugarbeets (Beta vulgarisL.) at harvest were aberrant in the zone of the hypocotyledonary neck when 0.84 kg/ha of α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine (trifluralin) was sprayed primarily on the hypocotyledonary tissues of seedlings in the 10 to 12-leaf stage, compared to 7% when soil surrounded most of the hypocotyledonary tissues at the time of application. Trifluralin did not reduce the yield of roots or kilograms of sucrose per hectare in either treatment. Sucrose content and purity were lower, and total nitrogen was more than twice as high in sections of neck and root tissues where the aberrations were the most severe as compared to normal sections of neck and root tissues from the untreated plots. In the greenhouse, trifluralin inhibited the growth of primary and lateral roots in sugarbeet seedlings.