Abstract: The monkshood-tuber of Aconitum kusnezoffii is a specialized structure attached to the root of the plant and is composed of apical bm4, axillary bud and its tuberous adventitious root. After the axillary bud emerges at the end of March of the following year, the primordium of the adventitious root develops from the procambium-like cells of the bud just below the first node at the abaxial part. With the active proliferation of the secondary phloem parenchyma ceils, the root increases its size very rapidly to form a “tuber”, When the adventitious root begins to develop, the first internode of the axillary bud extends horizontally to form a "bridge" connecting the daughter monkshood-tuber to the mother plant. In the third spring, each “tuber” sprouts one shoot giving rise to a new plant and in likewise produces a new “tuber”. It might be concluded that the monkshood-tuber is a renewal bud developing from a axillary bud. The so called “bridge” which connect the “tuber” and the mother plant is a special kind of subterraneous stem which is actually the first internode of the axillary bud.

Key words: Aconitum kusnezoffii Reichb., Monkshood-tuber, Adventitious root, Renewal bud