不同氮肥对油菜B与Mo吸收的影响

利用盆栽试验研究了潮土中不同氮肥对油菜硼钼吸收的影响，结果表明，前期(5周)施氮并没有促进油菜的生长，而且大部分氮肥对油菜生长表现抑制作用，氯化铵处理的作用最大，硫酸铵和尿素处理次之，硝酸铵处理再次之；不同氮肥均有抑制油菜生长前期(5周)硼吸收和累积的作用，其中以氯化铵、硝酸铵和尿素的作用为甚；不同氮肥同样抑制油菜生长前期(5周)对钼的吸收和累积，以硫酸铵处理作用最突出，氯化铵处理次之。但随着时间的推移，10、15周不同氮肥大多促进油菜的生长，增加油菜对硼钼的吸收和累积，且各氮肥处理间的差异逐步减小。

Effects of different nitrogen fertilizers on the uptake of boron and molybdenum by rape

The effects of different nitrogen fertilizers on the uptake of boron and molybdenum of rape in calcareous soil were inves- tigated in a pot experiment. The results indicated that except calcium nitrate, all nitrogen fertilizers decreased the growth of rape at the initial stages, and the growth of rape followed the order: calcium nitrate > ammonium nitrate > urea ?ammonium sulphate > ammonium chloride. All nitrogen fertilizers depressed the boron uptake of rape, and the effects of ammonium chloride, ammonium nitrate and urea were much greater than the others. And all nitrogen fertilizers decreased the molybdenum uptake of rape, especially ammonium sulphate and ammonium chloride. However, with cultivation time increasing, almost all nitrogen fertilizers increased the growth of rape as well as the uptake of boron and molybdenum, and the difference among these different nitrogen fertilizers became weakened.