ダイコンにおける自家並びに交雑不和合性の遺伝学的研究(第2報)

抄録

1. In these experiments two varieties, Tokina-shi and Nerima, were used as materials. Fertility was determined by pollen behavior on stigmas instead of by seed counts.
2. The results of self-and cross pollinations in variety Tokinashi were exceedingly complex. Ten plants examined were divided into eight classes on the basis of cross-relations. All these plants were self-incompatible. In inter-class pollinations there were both cross-compatible and -incompati-ble combinations. Differences in the reciprocal reactions between certain classes were also found (Table 1 and Diagram 1).
3. Self-and cross-pollinations in sister plants obtained by bud-selfing a self-incompatible plant (No. 9 in Diagram 1) were attempted in 1955 as progeny test. These ten plants were divided into three classes (α, β and γ). Classes α and β were cross-compatible in both directions, but all other
combinations were fully incompatible (Table 2 and Diagram 2).
4. The results of self-and cross-pollinations in variety Nerima were analogous to those of variety Tokinashi (Table 3 and Diagram 3).
5. These results closely resemble those of variety Shogoin (TATEBE 1944), and may well be explained if the following items are assumed:
(a) Both self- and cross-incompatibility are determined by two pairs of incompatible genes (S and I). S is assumed to be epistatic to I, but hypostatic to II (S>I, S<II).
(b) The interactions in fertilization. are determined by the sporophytic origin of pollen. A genetic explanation for the results was given in diagrams 4, 5 and 6.
This interpretation is analogous to RILEY'S hypothesis on Capsella (1932, 1936).