Effects of Metribuzin on the Performance of Soybean Cultivars

The response of seven soybean (Glycine max (L.) Merrill) cultivars to 0.56, 0.84 and 1.12 kg/ha pre-emergence applications of metribuzin [4-amino-6-tert-butyl-3-(methylthio)-as-triazin-5(4H)-one] was evaluated in Brookston clay loam soil. Slight foliar injury and stand reduction occurred at 0.56 kg/ha but damage became more severe as the rate was increased to 0.84 and 1.12 kg/ha. Plant height and bottom pod height were also reduced as the metribuzin rate was increased. Yield reductions occurred with the Steele and Harlon cultivars at the 1.12 kg/ha rate. Harosoy 63 was the cultivar most tolerant to metribuzin with Amsoy 71, Wells and Evans showing moderate damage and Steele, Harlon and XK-505 being the most sensitive.