抄録
This experiment was conducted in order to clarify the relation between a property of the seed materials in rice plants and their infiuence on the X-ray susceptibility. Ninety seeds of each seedgrown origin (Table l) were treated with 13, 000 runits (60kVP, 4mA) of X-rays. The results of the 1 st generation are given in Table 6. The differences to X-ray susceptibility occurred in the seed material of different seed-grown origins. The change in X-ray susceptibility within a variety is probably due to secondary property of physiological conditions rather than a primary effect of seed size. Various chlorophyll mutations were induced in the 2 nd generation (Fig. 1). In according to the Table 7, the high freuency of chlorophyll mutation in "Kairyo Aikoku " was observed in comparisbn with "Norin No 1 "
