Observations on the growth cycles of roots, shoots, and berries of grapes were undertook at the vineyard of Kotobukiya Institute of Viticulture near Kofu city from 1955 to 1957. Materials used were nonbearing and bearing vines of Black Queen variety. 1. Root growth started in the latter part of April and reached its height in new root formation and elongation in the middle and latter parts of July. It had another peak in the latter part of October, and was observed to be rather restricted between the two peaks. Its growth was ceased from the early part of December through the middle of April in the following year. 2. Shoot growth started in middle April with emergence of buds, and was the most vigorous from early June through middle July. Its growth was ceased in middle September. 3. Berry growth was the most conspicuous from late July through early August. 4. Growth cycle of the grapevine as a whole was shown to be made of the following sequence (Figs. 1, 2 and 3) at first shoots started to grow, root growth followed, then berries made a rapid growth. After the berries matured, the second peak of root growth occurred, then the vine lost its leaves and became dormant.
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