Blackberry

The blackberry is an edible fruit produced by any of several species in the Rubus genus of the Rosaceae family. The fruit is not a true berry; botanically it is termed an aggregate fruit. The plants typically have biennial canes and perennial roots. Blackberries and raspberries are also called caneberries or brambles. It is a widespread, and well known group of over 375 species, many of which are closely related apomictic microspecies native throughout the temperate northern hemisphere and South America.^[1]

Contents 1 Growth and anatomical description 2 Cultivation and uses 2.1 Commercial cultivars 3 Nutrients and antioxidant qualities 3.1 Nutrient content of seeds 4 Superstition and myths 5 Gallery 6 See also 7 References 8 External links

Growth and anatomical description

Blackberries are perennial plants which typically bear biennial stems ("canes") from the perennial root system.^[2]

In its first year, a new stem, the primocane, grows vigorously to its full length of 3-6 m (in some cases, up to 9 m), arching or trailing along the ground and bearing large palmately compound leaves with five or seven leaflets; it does not produce any flowers. In its second year, the cane becomes a floricane and the stem does not grow longer, but the flower buds break to produce flowering laterals, which bear smaller leaves with three or five leaflets.^[2] First and second year shoots are usually spiny with numerous short curved very sharp thorns (thornless cultivars have been developed purposefully). Recently the University of Arkansas has developed primocane fruiting blackberries that grow and flower on first year growth much as the primocane (also called fall bearing or everbearing) fruiting red raspberries.

Unmanaged mature plants form a tangle of dense arching stems, the branches rooting from the node tip on many species when they reach the ground. Vigorous and growing rapidly in woods, scrub, hillsides and hedgerows, blackberry shrubs tolerate poor soils, readily colonizing wasteland, ditches and vacant lots.^[1][3]

The flowers are produced in late spring and early summer on short racemes on the tips of the flowering laterals.^[2] Each flower is about 2-3 cm in diameter with five white or pale pink petals.^[2] The newly developed primocane fruiting produces flowers and fruits on the new growth.

The drupelets only develop around ovules that are fertilized by the male gamete from a pollen grain. The most likely cause of undeveloped ovules is inadequate pollinator visits.^[4] Even a small change in conditions, such as a rainy day or a day too hot for bees to work after early morning, can reduce the number of bee visits to the flower, thus reducing the quality of the fruit. However, the early flowers typically form more drupelets than the later ones because the early flower buds develop over a longer period during the dormant period. Incomplete drupelet development can also be a symptom of exhausted reserves in the plant's roots, or infection with a virus such as Raspberry bushy dwarf virus.

In botanical terminology, the fruit is not a berry, but an aggregate fruit of numerous drupelets ripening to black or dark purple.

Blackberry leaves are food for certain caterpillars; some grazing mammals, especially deer, are also very fond of the leaves. Caterpillars of the concealer moth Alabonia geoffrella have been found feeding inside dead blackberry shoots.

Cultivation and uses

Primary cultivation takes place in the state of Oregon located in the United States of America. Recorded in 1995 and 2006: 6,180 acres (25.0 km²) to 6,900 acres (28 km²) of blackberries, producing 42.6 to 41.5 million pounds, making Oregon the leading blackberry producer in the world.^[5][6] While Oregon may lead the world in volume of fruit produced, Serbia has tremendous acreage and Mexico has had dramatically increasing acreage and may soon lead the world.

The soft fruit is popular for use in desserts, jams, seedless jellies and sometimes wine. It is often mixed with apples for pies and crumbles.

Good nectar producers, blackberry shrubs bearing flowers yield a medium to dark, fruity honey.

The blackberry is known to contain polyphenol antioxidants, naturally occurring chemicals that can upregulate certain beneficial metabolic processes in mammals. The astringent blackberry root is sometimes used in herbal medicine as a treatment for diarrhea and dysentery.^[7] The related but smaller dewberry can be distinguished by the white, waxy coating on the fruits, which also usually have fewer drupelets. (Rubus caesius) is in its own section (Caesii) within the subgenus Rubus.

In some parts of the world, such as in Australia, Chile, New Zealand and the Pacific Northwest region of North America, some blackberry species, particularly Rubus armeniacus (syn. R. procerus, 'Himalaya') and Rubus laciniatus ('Evergreen') are naturalised and considered an invasive species and a serious weed.^[1]

As there is forensic evidence from the Iron Age Haraldskær Woman that she consumed blackberries some 2500 years ago, it is reasonable to conclude that blackberries have been eaten by humans over thousands of years.

Commercial cultivars

Numerous cultivars have been selected for commercial and amateur cultivation in Europe^[1] and United States.^[8] Since the many species form hybrids easily, there are numerous cultivars with more than one species in their ancestry.

'Marion' (marketed as "marionberry") is an important cultivar that was selected from seedlings from a cross between 'Chehalem' and 'Olallie' (commonly called "olallieberry") berries.^[9] It is claimed to "capture the best attributes of both berries and yields an aromatic bouquet and an intense blackberry flavor". The marionberry was introduced by George F. Waldo of the USDA-ARS in Corvallis, Oregon in 1956. Adapted to Western Oregon, the marionberry is named after Marion County, Oregon, in which it was tested extensively. 'Olallie' in turn is a cross between loganberry and youngberry. 'Marion', 'Chehalem' and 'Olallie' are just three of many trailing blackberry cultivars developed by the United States Department of Agriculture Agricultural Research Service (USDA-ARS) blackberry breeding program at Oregon State University in Corvallis, Oregon.

The most recent cultivars released from this program are the thornless cultivars 'Black Diamond', 'Black Pearl' and 'Nightfall' as well as the very early ripening 'Obsidian' and 'Metolius'. 'Black Diamond' is now the leading cultivar being planted in the Pacific Northwest. Some of the other cultivars from this program are 'Waldo', 'Siskiyou', 'Black Butte', 'Kotata', 'Pacific' and 'Cascade'.^[10]

Trailing blackberries are vigorous, crown forming, require a trellis for support, and are less cold hardy than the erect or semi-erect blackberries. In addition to the U.S. Pacific Northwest, these types do well in similar climates such as the United Kingdom, New Zealand, Chile, and the Mediterranean countries.

Semi-erect, thornless blackberries were first developed at the John Innes Centre in Norwich, UK, and subsequently by the USDA-ARS in Beltsville, Maryland. These are crown forming, very vigorous, and need a trellis for support. Cultivars include 'Black Satin' 'Chester Thornless', 'Dirksen Thornless', 'Hull Thornless', 'Loch Ness', 'Loch Tay', 'Merton Thornless', 'Smoothstem' and 'Triple Crown'. Recently, the cultivar 'Cacanska Bestrna' (also called 'Cacak Thornless') has been developed in Serbia and has been planted on many thousands of hectares there.

The University of Arkansas has developed cultivars of erect blackberries. These types are less vigorous than the semi-erect types and produce new canes from root initials (therefore they spread underground like raspberries). There are thornless and thorny cultivars from this program, including 'Navaho', 'Ouachita', 'Cherokee', 'Apache', 'Arapaho' and 'Kiowa'. They are also responsible for developing the primocane fruiting blackberries such as 'Prime-Jan' and 'Prime-Jim'.

In raspberries, these types are called primocane fruiting, fall fruiting, or everbearing. 'Prime-Jim' and 'Prime-Jan' were released in 2004 and are the first cultivars of primocane fruiting blackberry. They grow much like the other erect cultivars described above, however the canes that emerge in the spring, will flower in mid-summer and fruit in late summer or fall. The fall crop has its highest quality when it ripens in cool mild climate such as in California or the Pacific Northwest.

'Illini Hardy' a semi-erect thorny cultivar introduced by the University of Illinois is cane hardy in zone 5, where traditionally blackberry production has been problematic, since canes often failed to survive the winter.

The blackberry tends to be red during its unripe ("green") phase, leading to an old expression that "blackberries are red when they're green".

In various parts of the United States, wild blackberries are sometimes called "Black-caps", a term more commonly used for black raspberries, Rubus occidentalis.

Blackberry production in Mexico has expanded enormously in the past decade. While once based on the cultivar 'Brazos', an old erect blackberry cultivar developed in Texas in 1959, the Mexican industry is now dominated by the Brazilian 'Tupy' released in the 1990s. 'Tupy' has the erect blackberry 'Comanche' and a "wild Uruguayan blackberr" as parents.^[11] Since there are no native blackberries in Uruguay, the suspicion is that the widely grown 'Boysenberry' is the male parent. In order to produce these blackberries in regions of Mexico where there is no winter chilling to stimulate flower bud development, chemical defoliation and application of growth regulators are used to bring the plants into bloom.

Nutrients and antioxidant qualities

Blackberries are notable for their high nutritional contents of dietary fiber, vitamin C, vitamin K, folic acid - a B vitamin, and the essential mineral, manganese (table).

Nutrients in raw blackberries^[12]

Nutrient	Value per 100 grams	% Daily Value
Energy	43 kcal
Fiber, total dietary	5.3 g	21%
Sugars, total	4.9 g
Calcium, Ca	29 mg	3%
Magnesium, Mg	20 mg	5%
Manganese, Mn	0.6 mg	32%
Copper, Cu	0.2 mg	8%
Potassium, K	162 mg	5%
Sodium, Na	1 mg	0%
Vitamin C, total ascorbic acid	21 mg	35%
Vitamin A, IU	214 IU	4%
Vitamin K, µg	20 µg	25%
Folic acid, µg	36 µg	9%
Carotene, beta	128 µg	ne
Lutein + zeaxanthin	118 µg	ne

ne: Daily Value not established

Blackberries rank highly among fruits for antioxidant strength, particularly due to their dense contents of polyphenolic compounds, such as ellagic acid, tannins, ellagitannins, quercetin, gallic acid, anthocyanins and cyanidins.^[13][14]

Blackberries have an ORAC value (oxygen radical absorbance capacity) of 5347 per 100 grams, including them among the top-ranked ORAC fruits. Another report using a different assay for assessing antioxidant strength placed blackberry at the top of more than 1000 antioxidant foods consumed in the United States.^[15]

Nutrient content of seeds

Blackberries are exceptional among other Rubus berries for their numerous, large seeds not always preferred by consumers. They contain rich amounts of omega-3 (alpha-linolenic acid) and -6 fats (linoleic acid), protein, dietary fiber, carotenoids, ellagitannins and ellagic acid.^[16]

Superstition and myths

Superstition in the UK holds that blackberries should not be picked after Michaelmas (29 September) as the devil has claimed them, having left a mark on the leaves by urinating on them. There is some value behind this legend as after this date wetter and cooler weather often allows the fruit to become infected by various molds such as Botryotinia which give the fruit an unpleasant look and may be toxic.^[17][18]

Gallery

Blackberry bush in late June in UK.	Blackberry bush in late July in Germany.	13 August 2007, Manchester, England. Bramble; in background unripe fruit on second-year side shoots; late flowers from tip-flowering of first-year growth	A wild blackberry vine	Blackberry fruit
Many ripe blackberries	Thorns	Pollinated, developing blackberry		Blackberries
Blackberry bush and blossoms in Perrot State Park, Trempealeau County, Wisconsin

See also

• Black Raspberry, a North American fruit sometimes confused with blackberries.
• Kotata Berry, USDA-ARS release in cooperation with Oregon State University.
• Redberry mite, a common pest of North American blackberry crops.
• List of Lepidoptera that feed on Rubus

References

This article incorporates text from the public domain 1911 edition of The Grocer's Encyclopedia.

External links

• BBC h2g2 article on Blackberries
• Botanical Information from Mark's Fruit Crops, by Mark Rieger
• USDA Plants Classification Report
• From Idea to Supermarket:The Process of Berry Breeding Article on berry breeding including pictures of blackberry emasculation and pollination

Rubus Black raspberry • Blackberry • Bush lawyer • Ceylon raspberry • Dewberry • Hill raspberry • Mysore raspberry • Raspberry • Red raspberry leaf • Rubus subg. Chamaebatus • Swamp dewberry • Thimbleberry • White blackberry • Rubus arcticus • Rubus armeniacus • Rubus azuayensis • Rubus calycinus • Rubus chamaemorus • Rubus cockburnianus • Rubus coreanus • Rubus crataegifolius • Rubus deliciosus • Rubus glaucifolius • Rubus hawaiensis • Rubus hayata-koidzumii • Rubus hispidus • Rubus idaeus • Rubus laciniatus • Rubus laegaardii • Rubus lasiococcus • Rubus leucodermis • Rubus macraei • Rubus moluccanus • Rubus nivalis • Rubus niveus • Rubus occidentalis • Rubus odoratus • Rubus parviflorus • Rubus parvifolius • Rubus pensilvanicus • Rubus phoenicolasius • Rubus probus • Rubus rosifolius • Rubus saxatilis • Rubus sieboldii • Rubus spectabilis • Rubus strigosus • Rubus thibetanus • Rubus trifidus • Rubus ulmifolius • Rubus ursinus