Response of Four Soybean Cultivars to Metribuzin

The effect of metribuzin at six rates of application was evaluated on four soybean ( Glycine max L.) cultivars and on common hempnettle ( Galeopsis tetrahit L.) over a three-yr period (1985 to 1987). The cultivars Maple Amber and Baron were susceptible to metribuzin whereas the cultivars Maple Isle and KG-20 were tolerant of metribuzin. Metribuzin caused progressively greater reductions in plant stands and loss in yield in the susceptible cultivars as rate of application increased. Metribuzin at 0.5 kg ha -1 or higher controlled over 90% of common hempnettle.