Studies on Branching Habits in Crop Plants. : 5. Growth of tiller buds and terminal buds in rice and barley seedlings on artificial agar medium as affected by concentration of auxin.

[摘要] Rice and barley seedlings which were raised out of doors were used as plant material. Tiller buds which had been growing and terminal buds were taken out from these seedlings and were grown on artificial agar medium supplied with various concentrations of IAA from 10-4 to 10-7 M and zero under the condition of presence or absence of gibberellic acid and kinetin, in order to get basic information as to the relationship between the growth of tiller buds and growth substances. In case of barley, the growth of the tiller buds without LAA was much better than that with IAA. The growth was poor at the concentration 10-5 M which has been recognized to be the optimal concentration for the growth of shoots in various kinds of plants. The growth to terminal buds showed almost the same behavior as that of tiller buds to various concentrations of IAA. In case of rice, on the other hand, the growth of tiller buds was highest at the concentration of 10-5 M of IAA, being very poor without IAA. The growth of terminal buds of rice without IAA was inferior to that with IAA. In any case of the experiments reported here, no tendency was recognized that the optimal concentration of IAA for the growth of tiller buds is lower than that for terminal buds as suggested sometimes to explain the reason why auxin produced at the terminal bud inhibits the growth of the axillary buds. Besides, in most of the tiller buds and terminal buds of rice plants, roots developed, unlike in case of barley in which very little root development took place.

[学科分类] 农业科学（综合）