Effect of herbicides on soil dehydrogenase and urease activity in soybean (Glycine max)

A field experiment was conducted during (kharif) rainy season 1996-97 to as sess the effect of different herbicides applied to soybean (Glycine max (L. ) Merr.) on soil dehydrogenase and urease activity. The results indicated n o significant effect on soil dehydrogenase activity with the application of propaquizafop and imazethapyr over the control. Application of alachlor, p ropaquizafop and imazethapyr stimulated urease activity, while fenaxyprop d id not significantly change the same over the control. Among the herbicides , anilophos showed maximum inhibition in soil dehydrogenase and urease acti vity. Seed yield increased with the application of propaquizafop followed b y fenaxyprop in 1996 and imazethapyr followed by trifluralin and propaquiza fop in 1997. Seed Yield had positive association with dehydrogenase and ure ase activity.