Effect of N Forms on Growth and Root Physiological Characteristics of Wheat Seedling

Water culture experiment was conducted in laboratory room using wheat as an indicating crop to study the influence of different N forms on the growth,root physiological characteristics and nitrogen accumulation of seedling stage.There were 4 treatments in the experiment,which are respectively N1-ammonia nitrogen,N2-nitrate N,N3-Amid-N,N4-20% ammonia nitrogen + 80% Amid-N.The results show that N forms has significant effect on the growth of wheat seedling.In the nitrate nitrogen treatment,leaf weight and total biomass are the highest,and the daily gain is 34.5% higher than that of ammonium nitrogen.Nitrate nitrogen fertilizer can improve the root dry weight and root / shoot ratio,and it can increase the soluble sugar of the root system,and nitrate reductase activity ( NRA) .N uptake efficiency and nitrogen partial factor productivity ( PEP) are the highest in four treatments.Wheat having preference for nitrate nitrogen nutrition is well proved in aquiculture conditions.The nitrate nitrogen efficiency is superior to other forms.Mixed nitrogen source is the second smallest.Ammonium nitrogen is slightly above the amide nitrogen,but the difference is not significant.