Radiobiological Studies in Plants : IX. Further studies on the growth inhibition by radiations from the nuclear reactor, JRR-1

Abstract

Dry seeds of Triticum monococcum and Avelea strigosa were irradiated in the beam holes No. 7 and No. 16 of the Japan Research Reactor No. 1 (JRR-1). Seeds of T. mauococcum were more radio-sensitive than those of A. strigosa. After irradiation with the same neutron doses, 3.7∼11.5x10¹²n^th/cm², the seedling growth was more inhibited by treatments in the hole No. 16 than in the hole No. 7. The reasons that caused such different inhibitions were discussed, with special reference to the dose rate effect. When the seeds set in two layers were irradiated in the hole No. 7, it was noted that seedlings from the inner layer were usually more damaged than those from the outer one. Radiation-shielding effect by the seeds in the inner layer might be involved in this phenomenon.