FRUITS

What is a fruit?

Botanically, a fruit is a mature or ripened ovary to include its contents and any adhering accessory structures. This encompasses virtually everything laymen refer to as fruits and nuts and also a number of so-called vegetables such as tomatoes (berry), squash, cucumber, and eggplant and grains such as corn and wheat.

FRUITS (In the commercial sense)

The Rosaceae has many members that are cultivated for their edible fruits

1. Subfamily Pomoideae - fruit a pome
Malus - apple - originated in Old World (Western China)
Pyrus - pear - Old World origin, introduced by English or Spanish
Cydonia - quince

Fleshy part of fruit is floral cup, the wall of the ovary is the thin layer that surrounds core.

Apples are the most important economically, pears are next; quince is used mostly in preserves as it is very tart.

Superior varieties are grafted onto various rootstocks. The number of cultivars available has diminshed greatly.

2. Subfamily Prunoideae - fruit a drupe

All important fruit-producing taxa are in the genus Prunus

Fruit is a drupe which has 3 components
1. Exocarp - skin
2. Mesocarp - fleshy part
3. Endocarp - "pit" containing the seed.

Prunus domestica - plum, drying yields prunes

Prunus avium and P. cerasus - cherries

Prunus persica - peaches, nectarines; nectarines are a hairless mutant of peaches

Prunus armeniaca - apricots, Center of origin - central or western China

Prunus amygdalus - almonds - endocarp and seed only, considered a nut.

Peaches are most important economically in this group and are 3rd overall behind oranges and apples.

3. Subfamily Rosoideae - "false" fruits

1. Fragaria ananassa - strawberry, New World, resulted from a corss between F. virginiana and F. chiloensis in a European garden. Actual fruit is an achene, the fleshy part is derived from the receptacle.

2. Rubus occidentalis - blackberry - North America native, fruit an aggregate formed from several separate ovaries within a single flower.

3. Rubus idaeus - raspberry - Europe, fruit is same as R. occidentalis

Many local species of Rubus grow wild and are collected, quality of fruit is highly variable in wild plants.

Grossulariaceae - Currants and Gooseberries

Ribes nigrum - European black currants

Ribes sativum - red "cherry" currants

Ribes uva-crispa - gooseberries

Used in jams, liquers, pies

Fruit is an accessory berry which is berrylike but is produced from an inferior ovary so it contains accessory structures.

Currants are host to pine blister rust so they cannot be grown in the U.S. where pines are grown commercially.


Ericaceae - Blueberries and Cranberries

Vaccinium corymbosum - blueberries
Vaccinium angustifolium - blueberries

Blueberries prefer acid soil so they are very difficult to grow in this area. However, local growers can get around this problem by grafting cuttings from the above taxa to the rootstocks of the native local Vaccinium, which is adapted to grow in the local soils.

Vaccinium macrocarpon - cranberries
Vaccinium oxycoccus - cranberries

Cranberries are grown in boggy areas and are harvested by flooding the orchards, knocking the berries off the bushes and picking them off the surface of the water.

Vitaceae - Grapes

Vitis vinifera - perennial native to the Mediterranean, used for wines and table grapes

Vitis labrusca - fox grape, from Northeastern U.S., concord and catawba grapes, important for grape juice and jams

Fruit is a berry, raisins are dried grapes

Oleaceae - Olives

Olea europaea - native to the Meditteranean

Fruit is a drupe, mostly used for oil, untreated olives are very bitter.

Nuts are dry fruits where the edible portion is an embryo with enlarged cotyledons.

Juglandaceae - Walnuts and Pecans

Juglans regia - English walnut - walnut of commerce
Juglans nigra - Black walnut - not used to any large degree

Carya illinoinensis - native to Mexico and American Southwest; Breeding has developed thin shells "paper shells"

Fagaceae - Chestnuts

Castanea dentata - American Chestnut - All fruit-bearing trees have been destroyed by blight. Japanese Chestnut, C. crenata, which is resistant to blight is being planted in North America

Corylaceae - Hazelnuts

Corylus avellana - European in origin, also known as filberts or cob nuts; much more widely used in Europe than in U.S.

Almonds (covered under fleshy fruits)

Anacardiaceae - Pistachio

Pistacia vera - Central Asia and Eastern Meditteranean

Fruits are drupes, nut is seed enclosed by endocarp. Member of same family as poison ivy.

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