The effect of the non-uniform distribution of urea on crop growth

Abstract

Experimental studies, under field conditions, were conducted on wheat (var. Hilgendorf 61) and ‘Tama’ ryegrass (Lolium multiflorum var.) to determine the effect of non-uniform distribution of urea on their stand, overall dry matter yield, dry matter weight and nitrogen uptake per plant or unit row length. The primary objective was to obtain information which would serve as a guide in choosing suitable application spacing for liquid urea on these crops. Some aspects of urea as a fertilizer were revealed. Plot trials were performed at two nitrogen rates on wheat over two seasons and on ryegrass over one. The results shows that dry matter yield was not markedly dependent on application spacing up to 30-inch for wheat and 18-inch for ryegrass. The approximate distances over which individual plants responded to nitrogen were respectively 8 and 4 ½ inches from the line of application. The results from a comparison of surface (dribbling) and subsurface application methods over one season were rather inconclusive and further study is necessary. Some comments on the use of the data gathered and suggestions for further work are given.