Some effects of nitrification inhibitor (2-chloro-6(trichloromethyl)pyridine) on the use of fertilizer nitrogen and the growth of two wheat varieties

Abstract

A glasshouse experiment was done at Wagga Wagga, New South Sales to assess the value of a nitrification inhibitor2-chloro-6-(trichloromethyl)-pyridine ('N-serve' (R)) as a means of slowing down the rate of nitrification of ammonium added to a red earth soil. The effect of this chemical on the growth of a standard height and a semi-dwarf wheat variety was also assessed. The results indicate that a concentration of only 5 p.p.m. of the inhibitor in this soil slowed down the rate of nitrification of ammonium for up to 140 days. Although 'N-serve' was apparently phytotoxic to volunteer ryegrass and clover at the 5 p.p.m. level, the yield of wheat dry-matter after 60 days and grain at harvest were not significantly affected by concentrations of up to 10 p.p.m. in the soil. However, at the 10 p.p.m, level of inhibitor maturity was delayed.