人参的土壤营养与培肥研究 Ⅳ.用^(15)N示踪研究人参对NH_4^+—N和NO_3^-—N的相对吸收利用

STUDY ON THE RELATIVE ABSORPTION OF NH_4—N AND NO_3—N BY GINSENG USING ^(15)N AS A TRACER

用^(15)N示踪研究证明,二、三年生人参植株中,来自NH_4—N占全N百分数(Ndffa),分别相当于NO_3—N Ndffa的67.4和61.2％;NH_4—N的利用率,分别为NO_3—N利用率53.4和52.0％,后者明显优于前者。NO_3—N的Ndffn,两种年生人参,分别为豆饼—N的142.1和167.7％;利用率则分别为豆饼—N的120和119％,无机N显然更易被吸收。人参的营养生理特性,与多数旱田作物类似。

To study the relativeabsorption of NH_4—N and NO_3—N by ginseng, pot experiment with ^(15)N as a tracer was carried out. Theresultshowed that the Ndfa％ (the percentage of N derivedfromNH_4 ) in2and 3 years old ginseng was only 67.4％ and 61.2％ of Ndfn％ (thepercentage of N derived from NO_3) meanwhile the utilization rate of NH_4—N was 53.4％ and 52.0％ of that pofNO_3—N. ThustheNO_3—Nwasabsorbed more favourably than NH_4—N. However,it was alsoshownthat 2 and 8 years old ginseng obsorbed theNdfn％ of NO_3—N as many as 142.1％ and 167.7％ of thepercent of N derived from bean-cake powder respectively, and the utilization rate was 120％ and 119％ of thatofthe latter source. Therefore the inorganic nitrogen can easily be absorbed by ginseng. Fromthefact of relative absorptionof NO_3—Nand NH_4—N,it was evident that the nutritional chraacteristic of ginseng was similar toordinary farming crops.