采用大田试验方法，研究了不同氮源对烤烟根系生长及根际土壤养分有效性的影响。结果表明，在等氮量条件下，现蕾期和圆顶期的根系鲜重施硝铵磷处理比施尿素处理分别提高 19.61 %、29.85 %，根系氧化力分别提高23.11%、13.68%；土壤碱解氮在圆顶期根际、非根际分别增加了10.38%、9.97%，土壤速效磷在现蕾期和圆顶期根际分别增加了16.06%、12.76%。综合考虑，施用硝铵磷比施用尿素更有利于烤烟生长。

A field test method was conducted to investigate the effects of different nitrogen sources on tobacco root growth and and available nutrient of rhizosphere soil of tobacco. The results showed that the root fresh weight of application of ammonium nitrate and phosphorus treatment than in urea treatment increased by 19.61%， 29.85%， root oxidation increased by 23.11%， 13.68%， respectively， at budding stage and mature stage in the condition of equal amount of nitrogen； soil available nitrogen of the rhizosphere and non-rhizosphere increased by 10.38%， 9.91%， respectively， at mature stage， available phosphorus increased by 16.06%， 12.76% respectively， at budding stage and mature stage. Considering the application of ammonium nitrate and phosphorus is more than urea conducive to the growth of flue-cured tobacco.

S572.01