7
Figure 3. A slight whitish bloom can be seen on this
cluster of mature Thiessen fruit.
Photo: Bob Bors
Saskatoon berry fruit has three stages of
development that exhibit a sigmoidal (“S” shaped)
growth pattern. During stage one, fruit growth begins
slowly, then shows an increase; stage two, fruit
growth is fairly constant; stage three exhibits rapid
or exponential growth.
Pollination
Pollination is achieved by the transfer of pollen from
the anthers to the stigma in the same flower. Wild
plants exhibit two types of flowers: narrow, deep
floral cups, which may favour self-pollination, and
wide, open shallow floral cups, which may not favour
self pollination.
Studies at the University of Saskatchewan
determined that the flower structure encourages
insect pollination and that flowers are predominantly
self-pollinated; however, cross-pollination does
occur.
Floral scents differ from cultivar to cultivar, and these
scents determine the type of pollinators attracted to
the flowers. Some florets are scentless while others
are strongly scented, either sweet scented or
foul scented.
Moonlake, for example, is a sweet-scented cultivar
that attracts an abundance of pollinators, including
many types of bees. A carrion-scented variety,
which is covered with flies during flowering, has
been encountered in the Qu’Appelle Valley of
Saskatchewan.
Buds to berries
First bud break
•
flowers open
•
basal leaflets open just prior to petal tips
emerging
Second bud break
•
leaf buds elongated and cylindrical and lie flat
against the stem
•
leaves occur singly or alternately on stem
Leaf shape
•
circular or slightly ovate
•
margins serrated or singly toothed; teeth most
pronounced at top leaf
Flowers
•
5
green sepals and 5 white petals with
10
to 20 stamens and a central pistil
•
clustered along a central stem; cluster called
a raceme
•
easily killed by frost
Fruit
•
botanical name: a pome
•
frosts soon after flowering may damage
immature fruit
•
bloom or waxy covering
•
stalk (pedicil) 1 cm (0.4 in.)
•
clusters (racemes) hold 3 to 18 berries
•
ripen 6 to 8 weeks after flowering
•
single berry:
- 78 %
to 81 % water
- 19 %
sugar
•
benzaldehyde produces the characteristic
flavour and fruit fragrance