Attempts were made to clarify the translocation and distribution of nitrogen within peanut plant, by absorbing ^<15>NO_3-N only for 2 d at the flowering stage, and the early, middle and later stages of reproduction. The results obtained are as follows. The translocation of the ^<15>N absorbed at the flowering stage to the fruit was less than those at the reproductive stages, while ^<15>N of the developing leaves after the flowering stage did not remove to the other parts. The distribution of the ^<15>N absorbed at the early, middile and later stages to the fruit was about 15, 40 and 50% immediately after its absorption, respectively, and lastly reached to 62 and 65% at the early and middle stages. These results suggest that N absorbed at the vegetative stage is utilized to maintain the growth of the root, nodule, vegetative and fruit, and that N of the fruit is more dependent on N translocated from the root and nodule with its growth, while N retranslocating from vegetative parts to the fruit is more supported by the fixed or absorbed N at the early stage of reproduction.
