不同供磷水平对平邑甜茶生长及15N-尿素吸收和利用的影响

以盆栽平邑甜茶为试材,采用15N示踪技术研究了5个磷(P2O5)水平处理(0、400、600、800、1000 mg/kg)对平邑甜茶生长及15N-尿素吸收、分配和利用的影响。结果表明:随着施磷量的增加,植株的株高、茎粗、干重和叶面积均先增加后减少,400 mg/kg水平时植株正常生长,株高、茎粗、干重和叶面积最大,分别为27.72 cm、0.428 cm、8.07 g和15.12 mm2;1000 mg/kg水平时植株生长受抑制,株高、茎粗、干重和叶面积最小分别为21.86 cm、0.318 cm、6.13 g和13.73 mm2;植株不同器官(根、茎、叶)的Ndff值也表现出同样趋势。植株全氮、15 N吸收量、氮肥利用率随着施磷量的增加均表现出先增后减的趋势,400 mg/kg水平时植株全氮、15N吸收量和利用率最大分别为0.1146 g、0.0012 g和4.11%,600mg/kg水平时植株全氮,15N吸收量和利用率分别为0.1090 g、0.001 g和3.01%;800 kg/kg水平时,植株全氮,15 N吸收量和利用率分别为:0.0927 g、0.0007 g和2.23%,而1000 mg/kg水平时全氮、15N吸收量和利用率最小分别为0.0847 g、0.0007 g和2.04%。

EFFECT OF PHOSPHORUS ON GROWTH AND 15N ABSORPTION AND UTILIZATION OF MALUS HUPENHENSIS

In order to find out the effect of phosphorus(P2O5) on growth and N absorption,disbytribution and utilization,five phosphorus levels(0～1000 mg/kg) in the potted Malus hupenhensis were designedbyusing 15N trace technique.The results showed that plant height,stem diameter,dry weight and leaf area increased first with the level,then recreased with the increased levels of phosphorus fertilizer.The value of height,stem diameter,dry weight and leaf area were highest(27.72 cm、0.428 cm、8.07 g and 15.12 mm2) at 400 mg/kg level while the corresponding values of the plant parts were lowest(21.86 cm、0.318 cm、6.13 g and 13.73 mm2) at 1000 mg/kg level;Meanwhile,different parts of plant organ(root,stem and leaf) Ndff values showed the same trend among the five different levels.Plant total nitrogen,15 N uptake,nitrogen ratio were highest(0.1146 g、0.0012 g and 4.11%) under 400 mg/kg treatment,while those values were lowest(0.0847 g、0.0007 g and 2.04%) at 1000 mg/kg level.Plant totalnitryen,15N uptake,nitrogen ratio were 0.1090 g、0.001 g and 3.01%,under 600 mg/kg treatment,and 0.0927 g,0.0007g and 2.23%,under 800 mg/kg treatment.