蕎麥種子の Heteroauxin 處理による帯化現象誘導に關する研究 (豫報)

抄録

This paper deals with the fasciation experimentaly produced in buckwheat (Tochigi No. 1) by the treatment of seeds with the aqueous solution of heteroauxin.
1. In Experiment I, air dry seeds were soaked in 0.1% heteroauxin solution for 60, 50, 40, 30, 20 and 10 hours (Exp. I-A_??_F); in Experiment II, germinated seeds (having a seminal root of about 2_??_4mm long) were immersed in the same solution as in Exp. I for 40, 30, 20, 10 and 5 hours (Exp. II-A_??_E). In both experiments, the seeds treated with the solution were washed with water, and sown in the field to observe the effects of the treatment. In Experiment III, the germinated seeds, similar to those used in Exp. II, were injected with 0.1% heteroauxin solution at the top, and they were sown immediately without washing. In these experiments, the seed germination and the seeds soaking in the chemical were carried out in a thermostat kept at 25°C.
2. In these experiments, abnormal plants with two opposite leaves on the second node (the one above the cotyledon-node) were met with in very high proportions. Such abnormal plants were classified into 4 types (cf. Table 1), In Exps. I and II, the proportions of the abnormal plants to the total seedlings increased with the length of treatment. In Exp. I, the abnormalities other than (a) type were observed more frequently than in Exps. II and III.
In the cases where the seeds were treated for 40 and 30 hours, Exp. I shows higher ratios of abnormal plants than Exp. II, but in the case where the seeds were treated for 10 hours Exp. II shows higher ratio of abnormal plants than Exp. I; in the case of 20 hours no difference was observed between those experiments.
3. Fasciation occurs in some of the branches grown on the second node of the abnormal plants (Fig. 1). Fasciation is not observed in the branches produced on the successive normal node of the abnormal individuals. It was not observed also in the normal plants. Thus fasciation is always accompanied by the abnormalities.
From the facts represented in Table 2, it seems that the condition which induces fasciation also produces the abnormalities. In Exp. III, fasciation was not met with at all. It seems that the fasciation shows a tendency to appears somewhat more frequently in the abnormal individuals belonging to (b), (c) and (d) types than in that of (a) type.