ミトリササゲの発芽初期における澱粉粒の消長
ミトリササゲにおける形態形成の研究 第I報
1957 年 70 巻 827 号 p. 152-157
詳細
1957 年 70 巻 827 号 p. 152-157
1. Changes in the distribution and the amount of starch grains were observed following the development of various organs and tissues in young seedlings of a bean, Vigna sesquipedalis.
2. The amount of starch grains in the cotyledon decreases steadily as germination proceeds; after 24hr. the decrease is especially abrupt. Starch grains are first consumed in the outer portion of the cotyledon and the consumption proceeds then inward, and finally, on the 7th day, starch grains are observable only in the cells around the vascular bundles.
3. In the presumptive abscission region of the cotyledon, there is a marked accumulation of starch grains from the 2nd to the 5th day; on the 5th day the inception of a histologically detectable differentiation of abscission layer of the cotyledon appears.
4. The hypocotyl and the epicotyl possess a definite amount of starch grains at the beginning of germination; from 25 to 30hr. the amount of starch grains becomes minimum; soon after they increase again and on the 2nd day their amount reaches maximum; then they decrease gradually until the starch grains are almost all consumed on the 6th day, except for a few remaining in the starch sheath of the hypocotyl.
5. In the radicle, there is a heavy accumulation of starch grains in the root cap cells and markedly so in the starch sheath of the elongation zone, reaching a maximum on the 2nd day.
6. In the plumule, starch grains are first detectable only in the dorsal part adjacent to the midrib; on the 2nd day they locate throughout the dorsal mesophyll tissue and then they decrease gradually until on the 6th or 7th day a few starch grains are retained only in the cells beneath the midrib.
