Interaction of moisture storage at planting and nitrogen fertilization on wheat yield on a black earth

Abstract

None, 45, 90 and 180 lb/acre N as urea were applied at five levels of available moisture. Although growing-season rainfall was above average there was no response to N on unirrigated plots and in absence of N there was only a vegetative response to extra moisture. Grain-yield responses of 5-6 bu/ acre/cwt urea were achieved both with additional N and with additional water but the highest application rates of N and of water depressed yields. Additional water generally had a greater effect on vegetative growth than on grain yield but the effect of N was more evident in grain yield.