Perennial Temperate
Fruits
David S. Seigler
Department of Plant Biology
University of Illinois
Urbana, Illinois 61801 USA
seigler@life.illinois.edu
http://www.life.illinois.edu/seigler
Perennial temperate fruits Outline
Importance:
• fruits and nuts
• eaten in all cultures, large amounts
Botanical
• What is a fruit? Pericarp (endo-, meso-, and
exo-) see pg. 18-20, p. 53-57
• What is a nut? Seeds, table p. 62, 70-74
Properties:
• Nutritive
– Fruits
• sugars
• vitamins, minerals
• oils (olive, avocado)
– Nuts
• sugars
• oils
• protein
Reading
• CHAPTER 3 IN TEXT (p. 53) read pgs.
12-20
Introduction
• Contrast fruits with cereal grains and
legumes
• Economics of cultivation
• Preservation drying cold storage jellies
etc.
Most important fruits
• Rosaceae
– Apples - pomes - see pp. 57-64 - 50% of all fruit
production
– Prunus- drupes - plums (prunes), peaches,
cherries, apricots
• Vitaceae
– grapes - berries
Temperate Nuts
• Juglans regia (walnut)
• Prunus amygdalus (almond)
Types of fruits
• “Fruit” means different things to different
people.
• To botanists the term means a matured ovary
along with its contents and any adhering
accessory structures.
• Green beans, cucumbers and squash are
fruits. Tomatoes and eggplants are fruits.
• Fruits usually include seeds.
Parthenocarpic fruit
• Fruit and seed development can occur
without fertilization.
• Fruit that develops without seed
formation is "parthenocarpic".
• Fruit of this type have been selected
because they mature fruits
spontaneously without fertilization.
• Fruits are often classified by the number of
ovaries involved in their formation
• By the position of the ovary (superior or inferior)
• By whether the fruit is dry or fleshy at maturity
• By the way the fruit releases its seeds
(dehiscence).
• Table 3-1, p. 54
• GO OVER THIS TABLE (pg. 54)
• Simple fruits have seeds surrounded by three
layers:
• Endocarp
• Mesocarp
• Exocarp
• FIG. 3-3, pg. 57.
• Simple fruits indehiscent or dehiscent.
• Dry fruits and their seeds usually
dispersed by wind, water, or gravity.
• In grains or caryopses the seed coat is
fused to the ovary wall.
• In some other fruits, pericarp layers are
fleshy.
• If the fruit is produced by a single
superior ovary within a flower, the fruit is
a berry.
• Berries may contain one or more seeds.
• If the seed is enclosed in a hard
endocarp, the fruit called a drupe.
• Citrus fruits have a special type of berry
with a leathery rind, oil glands, and
specialized fleshy hairs.
• If the ovary is inferior, other floral parts are
attached to the ovary wall.
• Fruits of this type often called accessory
fruits.
• Many are commonly called berries.
• Those of the squash family are called pepos.
• If there are numerous, simple, superior
ovaries within a single flower, the fruit is
called an aggregate fruit, e.g.,
blackberries.
• Multiple fruits involve fusion of many
fruits from numerous separate flowers,
e.g. pineapple.
Composition of fruits
• Fleshy fruits evolved to attract animals that
eat them and disseminate the seeds.
• Fleshy part consists of flavored sugar
solutions without many nutrients.
• Fruits are good sources of water soluble
vitamins.
• Avocado and olive are exceptions.
• Table 3-3, p. 60.
Composition of seeds
• Seeds are quite different in composition
from fruits.
• Seeds usually have fats, oils and/or
starches.
• Seeds often protected by hard shells,
seed coats, and toxic compounds.
• Seeds usually high in nutritional energy.
• Table 3-4.
• Most fruits consumed raw.
• Fruits also preserved by drying, cold
storage, as jellies, preserves or
sugared, smoked or frozen.
• Fruits never basic to the diets of any
groups of peoples, but important in
many, especially in the Middle East, for
example.
Domestication of fruits
• Fruits have been used by huntergatherers up to the present.
• Although plants related to the ancestors
of most perennial fruit crops occur in
both the Old and New World, the crop
plants almost all came from the Old
World.
• A few New World ones have been
domesticated in the last 200-300 years
(e.g., the blackberry and the cranberry).
• Most perennial fruit crops are slow
growing trees or shrubs.
• Selection has not changed most of them
significantly with the exception of larger
fruits, better taste, disease resistance,
and lower toxicity.
• Most are still hand harvested.
• Where they are grown is largely
dependent on where labor is cheap.
Apples, Malus spp.
• Apples are the most important temperate fruit
tree in the world.
• Apples, pears, peaches, plums, cherries,
strawberries, blackberries, and quince all
come from the rose family, the Rosaceae.
• There are several types of fruits in this family.
• Apples are called "pome" fruits because of
the special type of fruit they have.
• Pg. 57-64 in the text.
Malus domestica, apple in flower
The Complete Book of Fruits &
Vegetables, F. Bianchini, F. Corbetta,
M. Pistola, Crown Publishers, New
York, 1973
Apple cultivars
• The genera Malus, Pyrus and Cydonia all
belong to the same subfamily.
• Apples account for 50% of the world's
deciduous fruit tree production.
• The genus Malus probably arose in Asia, but
spread to the Americas long before any
human came to this continent.
• All cultivated apples are native to the Old
World, probably from the Caucasus
Mountains.
• Good apple cultivars mostly cultivated by
grafting.
• We eat the "floral cup" of the apple.
• World production of fruits TABLE 3-5 Pg.
62-63.
• Large countries almost always lead in
production of crop plants, but they may
be relatively more important in small
countries or regions of a large country.
• Fruit crops usually require inexpensive
labor to be competitive.
Pears (Pyrus spp.)
• Pears probably the second most important
tree fruit crop.
• The pear may have arisen in sw Asia or in
China or both.
• No pears native to the New World.
• Pears usually propagated by grafting.
• Both pears and quinces are more popular in
Europe and the Orient than in the U.S.
Pyrus communis,
pears
The Complete Book of Fruits &
Vegetables, F. Bianchini, F. Corbetta,
M. Pistola, Crown Publishers, New
York, 1973
Fruits from the genus Prunus
• Several important fruits belong to the genus
Prunus.
• These include plums, cherries, peaches, and
apricots.
• The fleshy mesocarp is eaten. The fruits are
drupes.
• Most of this group seems to have arisen in
central or western China.
Prunus cerasus, cherry
cultivars
• These plants have been
cultivated in the Old World for
at least 2000 years.
• There are wild species of
cherries and plums in the New
World as well.
The Complete Book of Fruits &
Vegetables, F. Bianchini, F. Corbetta,
M. Pistola, Crown Publishers, New
York, 1973
Prunus angustifolia,
Chickasaw plum
Prunus armeniaca,
apricots
• Prunes are dried plums. Drying formerly was
the major method of preserving fruit.
Otherwise they would only be available in
season.
• Many grown as ornamentals and not for their
fruits.
• Peaches are the third most important fruit
crop in the U.S. (apples, oranges, peaches).
• Peaches usually propagated by grafting.
• Apricots first brought to Greece from Persia
by Alexander the Great. They were brought to
the New World by the Spanish.
The "Berries" of the fruit trade
• Strawberries, blackberries, raspberries are
not berries.
• Most of the strawberry is the receptacle on
which the ovaries are born.
• Strawberries native to both the Old and New
World. Fragaria virginiana in eastern North
America most common. F. chiloensis from
Chile.
• These two species hybridized in a botanic
garden in Europe about 1750 to produce the
commonly cultivated strawberry today (F.
ananassa).
Strawberries
The Complete Book of Fruits & Vegetables, F.
Bianchini, F. Corbetta, M. Pistola, Crown
Publishers, New York, 1973
Rubus sp.,
flowers and
aggregate fruits
Members of the genus Rubus are
native to both the Old and New World.
Representatives of both are cultivated.
Blueberries and cranberries both belong to the genus Vaccinium
(Ericaceae). This group is native to both North America and Europe/Asia.
Vaccinium angustifolia, lowbush blueberry
Harvesting
blueberries in Maine
Commercial cranberries
Grapes, Vitis vinifera
• One of the most important fruit crops in the
world. Will be discussed as a source of
alcoholic beverages later. Vitis vinifera
(Vitaceae) is the most commonly cultivated
species. Many table grapes produce poor
wine and different grape cultivars are usually
used for beverage production.
• The most important New World grape is V.
lambrusca. Concord and Catawba grapes
belong to this species.
Grapes, Vitis vinifera
The Complete Book of Fruits & Vegetables, F.
Bianchini, F. Corbetta, M. Pistola, Crown Publishers,
New York, 1973
Vineyards in Lausanne
Wild grapes
• Raisins are dried grapes. Again, formerly
drying was one of the major ways of
preserving fruits.
• “Fossils” of grapes known from Europe.
Grapes were cultivated by 5000 B.C. in India
and in S.E. Europe. In North America grapes
widely eaten by the Indians (but not
cultivated).
• Disease and insect pest problems will be
discussed later.
• Grape production in California highly
mechanized.
Olives (Olea europaea)
• Olives have been an important food and
source of oil for more than 5000 years. Olea
europaea (Oleaceae) native to the area at the
east end of the Mediterranean Sea. They still
grow wild there.
• Olive seeds have been found back as far as
3000 B.C.
• Fresh olives are extremely bitter and must be
detoxified.
• Olives processed by drying, salting, and
pickling.
• Only about 1-2% of the olive crop is eaten as
a fruit.
Wild olives from the
Middle East
Temperate nuts
• One seeded, indehiscent fruit, usually quite
hard. In the botanical sense, acorns and
hazelnuts are true nuts.
• Typically high in protein and lipid. Usually
hand harvested.
• Domestication - slow growing and frequently
vegetative reproduction.
• Used in all cultures, but not major in any
today.
• Many nut crops grown on arid, agriculturally
marginal lands where labor is cheap.
• The major nut crops are: walnut (English),
almond, and cashew (discussed under
Tropical Nut Crops). Ranking should consider
both tonnage and dollar value.
• From the archaeological record, it is clear that
many nuts were eaten in the past.
Acorns and hickory nuts
• Acorns and hickory nuts were major
food plants of many American Indian
groups of the eastern U.S. and also of
California.
Acorns, fruits of oaks, Quercus sp.
Fruit of Carya sp. in southern Illinois
• Walnuts, pecans, almonds, chestnuts, filberts
or hazel nuts are native to temperate regions
of the world.
• Pecans are the only common nut to come
from the New World.
• Peanuts are native to the South American
non-center (discussed under Legumes).
• In contrast to the fruits discussed above, nuts
are dry fruits.
• The edible portion is the embryo, which has
enlarged cotyledons.
• Table 3.4, p. 60, nutritional information.
Walnuts and Pecans
• The English walnut (Juglans regia,
Juglandaceae) (native to Iran) is the most
important temperate nut crop.
• In the United States, most walnuts grown in
California. Rich in oil.
• The pecan (Carya illinoensis) is native to
North America. Native to south central U.S.
and Mexico.
• "Paper shell" varieties now often cultivated.
Pecan orchards are common in the South,
e.g., in Texas, Oklahoma, Georgia etc. Some
in Australia and S. Africa.
Fruits of Juglans
regia
Almonds (Prunus amygdalus, Rosaceae)
• Almonds belong to the same genus as the
fruit crops we just discussed.
• The removal of the leathery mesocarp leaves
the seed inside the endocarp.
• The seeds of some cultivars are highly toxic.
Sweet and bitter almonds.
• Almonds originally cultivated as an oilseed
crop and later became a nut crop.
• In the U.S., almonds mostly grown in
California. Grown competitively because of
mechanization.
• High in protein.
Prunus amygdalus, almond
Hazel nuts (Corylus avellana, Corylaceae)
• Hazel nuts native to the Old World. This is the
common cultivated species.
• Other Corylus species occur in the New
World, e.g., Corylus americana.
• Hazel nuts are much more popular in Europe
than here.
• In the U.S., most come from Oregon (about
95%).
• High in oil.
Corylus avellana,
hazel nut