Effect of Trifluralin and Metribuzin Combinations on Soybean Tolerance to Metribuzin

In field trials, soybeans [ Glycine max (L.) Merr.] treated with trifluralin [α,α,α-trifluoro-2,6-dinitro- N,N -dipropyl- p -toluidine] at 0.56 and 0.84 kg/ha were protected from injury by metribuzin [4-amino-6- tert -butyl-3-(methylthio- as -triazine-5(4 H )one] at 0.28 to 1.12 kg/ha. Soybean injury from metribuzin at high soil pH values was reduced by applying it in combination with trifluralin. Trifluralin also protected soybeans from injury caused by low rates of atrazine [2-chloro-4-(ethylamino)-6-(isopropylamino)- s -triazine] greenhouse studies. The trifluralin treatment reduced root development and greatly reduced 14 C-atrazine and 14 C-metribuzin uptake and content within the soybean plant.