Analysis of the response by wheat to application of molybdenum in relation to nitrogen status

Abstract

The response of wheat to the application of molybdenum was studied on a fallowed site near Canberra, A.C.T. Application of molybdenum increased the yield of vegetative material and of grain by 50 to 60 per cent; the increases were somewhat smaller without applied nitrogen than with it. Form of nitrogen (urea or ammonium nitrate), rate (up to 90 kg ha-1), and method of application (drilled or broadcast) did not consistently affect the results. The results suggest that molybdenum status should be considered in conjunction with nitrogen supply where application of nitrogen in the field is followed by a decrease in grain yield, including those cases where grain filling is curtailed.