Agriculture Reference
In-Depth Information
Fig. 2.3
Cross sections of the two types of buds in deciduous broad-leaved trees. (
a
) Homonomous
bud of
Alnus hirsuta
with repetitions of the same basic unit of two stipules and a lamina. (
b
) Hetero-
nomous bud of
Ulmus davidiana
with bud scales at the outermost part of the bud distinctly different
from the embryonic leaves to the interior of the bud. (After Kikuzawa 1983)
Fig. 2.4
The linkage between the development of bud scales and shoot elongation patterns (Sakai
1990).
Dipteronia
, the closest relative of
Acer
, has no bud scales. In
Acer
species, young bud
scales have a rudimentary blade at their tips, which disappears during development, suggesting
bud scales originated from normal leaves. Minute rudimentary blades exist at the tip of the inner
bud scales in
Acer
species with
indeterminate
shoot growth but not in those with
determinate
shoot growth
