After removal of the ethanol solvent, the extractive, which is rich in lipid associates, was incubated in soil with 200ppm NH4-N at rates of 5 to 30% of the NH4-N. NH4-N was supplied by ammonium sulphate and urea. Inhibition of nitrification depended on the amount of the seed extract applied and on time of incubation; application at 30% of the NH4-N was effective up to 75 days
