Effect of Applying Nitrogen and Phosphorus Fertilizer on Alfalfa Seed Yield

This experiment was conducted to study the effect of fertilizer on alfalfa seed yield,especially,on phosphate,under the unique natural environment of Xinjiang.Experimental method is to determine the contents of nitrogen(N),phosphorus(P) in the topsoil of research district first and then,to add them according to their contents in soil.The object of this experiment was to explore the fertilizing quantity of nitrogen,phosphorus for alfalfa seed yield.Primary result indicated that P2O5 application had not improved alfalfa seed yield but decreased,only utilization of P2O5 had not any effect on alfalfa seed yield;A little amount of urea had significant effects on alfalfa seed yield.When the amount of fertilization exceeds 120 kg/hm2,alfalfa branch would be thin and long,and would weaken the reproduction growth ability,which caused its seed yield to be decreased;When the fertilization amount is 300㎏/hm2 which is considered the best quantity.Urea had certain effects on increasing of alfalfa seed yield.