Submitted to:

Dr. J S KANG

Senior Agronomist

Department of Agronomy

Submitted by

Amrik Singh

L-2008-A-1-M

Department of Agronomy

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Scientific classification

Kingdom: Plantae

(unranked): Angiosperms

(unranked): Monocots

(unranked): Commelinids

Order: Poales

Family: Poaceae

Subfamily: Pooideae

Tribe: Triticeae

Genus: Hordeum

Species: H. vulgare

INTRODUCTION2

Barley is a cereal grain derived from the annual grass Hordeum vulgare. It

serves as a major animal feed crop, with smaller amounts used for malting (in beer

and whisky) and in health food. In 2005 ranking of cereal crops in the world,

barley was fourth in quantity produced and in area of cultivation (560,000 km²). It

is still used as a food staple in the Middle East.

It is a member of the grass family. The domesticated form (H. vulgare) is

descended from wild barley (H. spontaneum) and they are inter-fertile. The two

forms are therefore often treated as one species, Hordeum vulgare, divided into

subspecies spontaneum (wild) and subspecies vulgare (domesticated). The main

difference between the two forms is the brittle spike on the seeds of the

spontaneum, which assists dispersal.

Barley is a self-pollinating, diploid species with 14 chromosomes. Wild

barley, Hordeum vulgare subsp. spontaneum, is abundant in grasslands and

woodlands throughout the Fertile Crescent and is abundant in disturbed habitats,

roadsides and orchards. Outside of this region the wild barley is less common and

is usually found in disturbed habitats.

ORIGIN AND HISTORY

Barley was one of the first crops domesticated in the Near East, at the same

time as einkorn and emmer wheat. Wild barley (H. vulgare ssp. spontaneum)

ranges from North Africa and Crete in the west, to Tibet in the east. The earliest

evidence of wild barley in an archaeological context comes from the Epipaleolithic

at Ohalo II at the southern end of the Sea of Galilee. The remains were dated to

about 17000 BC. The earliest domesticated barley occurs at Aceramic Neolithic

sites, in the Near East such as the Pre-Pottery Neolithic B layers of Tell Abu

Hureyra, in Syria. Barley has been grown in the Korean Peninsula since the Early

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Mumun Pottery Period (c. 1500–850 BCE) along with other crops such as millet,

wheat, and legumes.

Barley is believed to have originated in Abyssinia (Ethiopia) and South

East Asia. The cultivated barley of today is believed to have evolved from a wild

two row hordeum that has been classified as H. Spotaneum and is found growing

wild in many areas of south west Asia and northern Africa today.

Barley beer was probably the first drink developed by Neolithic humans.

Barley later on was used as currency. Alongside emmer wheat, Barley was a staple

cereal of ancient Egypt, where it was used to make bread and beer. According to

Deuteronomy 8:8, barley is one of the "Seven Species" of crops that characterize

the fertility of the Promised Land of Canaan, and barley has a prominent role in

the Israelite sacrifices described in the Pentateuch. A religious importance

extended into the Middle Ages in Europe, and saw barley's use in justice, via

alphitomancy and the corsned.

In ancient Greece, the ritual significance of barley possibly dates back to

the earliest stages of the Eleusinian Mysteries. The preparatory kykeon or mixed

drink of the initiates, prepared from barley and herbs, was referred to in the

Homeric hymn to Demeter, who was also called "Barley-mother". The practice

was to dry the barley grouts and roast them before preparing the porridge. This

produces malt that soon ferments and becomes slightly alcoholic.

In medieval Europe, bread made from barley and rye was peasant food,

while wheat products were consumed by the upper classes. Potatoes largely

replaced barley in Eastern Europe in the 19th century.

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Climatic requirements

Ranging from Boreal Moist to Rain through tropical Very Dry Forest Life

Zones, barley is reported to tolerate annual precipitation of 19 to 176 cm, annual

temperature of 4.3 to 27.5°C, and pH of 4.5 to 8.3. Bukantis and Goodman note

that barley has a wider ecological range than any other cereal grain. Barley has a

shorter growing season than wheat or oats and can be grown at higher latitudes.

Some varieties are grown in tropical India, in hot districts of Africa, and as far

north as 700N in Norway. In the United States it is grown in the cooler climates.

Among the cultivars, there are adaptations to almost any ecological situation, but

most do not thrive in the humid tropics. Some forms survive under extreme

conditions and mature in 60–70 days. Due to its ability to ripen at rather high

temperatures, the southern limit for its cultivation is 10°N of Equator. Barley is

not particularly winter-hardy, so is grown as a spring crop. In areas with

comparative mild winters as the Mediterranean and India, it is grown as a winter

crop. Average temperature during growing period is 15.5–17°C, preferably sunny

and moderately rainy. Grown on soils which are too light or otherwise unsuitable

for wheat cultivation; does well on light or sandy loam soil. Highest grades of

barley are grown on fertile deep loam soils with pH of 7–8. Soils lower than pH 6

may induce aluminum toxicity. For malting barleys, soils should not contain too

much nitrogen.

GROWTH AND DEVELOPMENT

The growth cycle of barley has the following divisions: germination,

seedling establishment and leaf production, tillering, stem elongation, pollination,

and kernel development and maturity

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Germination

The minimum temperature for germination of barley is 34 degrees to 36

degrees F (10 - 20C). After the seed takes up moisture, the primary root (radicle)

emerges. The radicle grows downward, providing anchorage and absorbing water

and nutrients, and eventually develops lateral branches. Other roots formed at the

level of the seed make up the seminal root system. These roots become highly

branched and remain active throughout the growing season.

After the radicle emerges from the seed, the first main shoot leaf emerges.

It is enclosed within the coleoptile for protection as it penetrates the soil. As a

result, the seeding depth should not exceed the length that the coleoptile can grow,

usually no more than 3 inches (7.6 cm)

Germinating barley kernels with radicle emergence

Seedling establishment and leaf production

Once the seedling has emerged, the coleoptile ceases elongating and the

first true leaf appears. Then leaves appear about every 3 to 5 days depending on

the variety and conditions.. Another way of quantifying leaf appearance is in terms

of accumulated heat units calculated by summing the number of degrees above 40 6

degrees F for each day*. About 100 heat units accumulate between the appearance

of successive leaves in a medium maturing barley. Eight or nine leaves are usually

formed on the main stem, with later maturing varieties usually forming more

leaves. Emergence of the final leaf, termed the flag leaf, is an important growth

stage for timing the application of certain growth regulators

First true leaf emerging through the coleoptile tip

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Seedling at two-leaf stage

The upper third of a plant at flag leaf emergence

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Tillering

When the seedling has about three leaves, tillers usually begin to emerge.

Ability of barley plants to tiller is an important method of adapting to changing

environmental conditions. When environmental conditions are favorable or if the

plant density is reduced, compensation is possible by producing more tillers.

Under typical cultural conditions for spring barley, tillers emerge during about a 2-

week span with the total number formed depending on the variety and

environmental conditions. Deep seeding and high seeding rates usually decrease

the number of tillers formed per plant. There may be more tillers formed when

early season temperatures are low, when the plant population is low, or when the

soil nitrogen level is high. Some tillers initiate roots, contributing to the nodal root

system. About four weeks following crop emergence, some of the previously

formed tillers begin to die without forming a head. The extent to which this

premature tiller death occurs varies depending on the environmental conditions

and the variety. Under poor or stressed growing conditions, plants respond by

forming fewer tillers or by displaying more premature tiller death.

Barley plant at early tillering showing a tiller

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Stem elongation

Until jointing, the plant apex or growing point is below the soil surface

where it is protected somewhat from frost, hail, or other mechanical damage.

Between 3 and 4 weeks after plant emergence, the upper internodes of the stem

begins to elongate, moving the growing point above the soil surface. The head also

begins to grow rapidly, although it is still too small to readily detect through the

surrounding leaf sheaths. During the "boot" stage, the head becomes prominent

within the flag leaf sheath

Boot stage in barley

Pollination flowering

Pollination usually takes place in barley just before or during head

emergence from the boot. Pollination begins in the central portion of the head and 10

proceeds toward the tip and base. This event occurs 6 to 7 weeks after crop

emergence. Since pollen formation is sensitive to stress, water deficits and high

temperatures at this time will decrease the number of kernels that form and may

reduce yields. These yield reductions can be diminished by planting early so that

pollination and early grain filling is completed before late season stresses occur.

Kernel development and maturity

Once head emergence and pollination have occurred, kernels begin to

develop. The length of the barley kernel is established first, followed by its width.

This helps explain why thin barley developed under stress conditions is usually as

long as normal grain, but is narrower. Figure 11 shows the physical changes as a

kernel develops. The first period of kernel development, designated the "watery

ripe" and "milk" stages, lasts about 10 days. Although the kernels do not gain

much weight during this phase, it is extremely important because it determines the

number of cells that will subsequently be used for storing starch. Kernels crushed

in this stage initially yield a watery substance which later becomes milky. Kernels

that are storing starch and growing rapidly are characterized by a white semi-solid

consistency termed "soft dough." This period usually lasts about 10 days following

the milk stage. Finally, as the kernel approaches maturity and begins losing water

rapidly, its consistency becomes more solid, termed "hard dough." This is when

the kernel also loses its green color.

When kernel moisture has decreased to about 30 to 40 percent, it has

reached physiological maturity and will not accumulate additional dry matter. The

final yield potential has been established at this time. An easily identified field

indicator of physiological maturity is 100 percent loss of green color from the

glumes and peduncle. Although the moisture content of the grain is still too high

for direct combining, it can be swathed and windrowed. When kernel moisture has

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decreased to 13 to 14 percent, the barley kernel is ready for combining and

threshing.

Kernel development

Physiological maturity in barley

USES of BARLEY

Algicide

Barley straw, in England, is placed in mesh bags and floated in fish ponds

or water gardens to help reduce algal growth without harming pond plants and

animals. Barley straw has not been approved by the EPA for use as a pesticide and

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its effectiveness as an algaecide in ponds has produced mixed results during

university testing in the US and England.

Animal feed

Half of the United States' barley production is used as an animal feed. [21]

Barley is an important feed grain in many areas of the world not typically suited

for maize production, especially in northern climates. Barley is the principal feed

grain in Canada, Europe, and in the northern United States.

Alcoholic beverages

A large part of the remainder is used for malting, for which barley is the

best suited grain. It is a key ingredient in beer and whisky production. Two-row

barley is traditionally used in German and English beers. Six-row barley was

traditionally used in US beers, but both varieties are in common usage now.

Distilled from green beer, whisky has been made from barley in Ireland and

Scotland, while other countries have utilized more diverse sources of alcohol; such

as the more common corn, rye and molasses in the USA. The grain name may be

applied to the alcohol if it constitutes 51% or more of the ingredients.

Non-alcoholic drinks such as barley water [5] and barley tea (called mugicha

in Japan), have been made by boiling barley in water. Barley wine was an

alcoholic drink made in the 1700s, prepared from recipes of ancient Greek origin.

It was prepared by boiling barley in water, the water from the barley was then

mixed with white wine, and other ingredients like borage, lemon and sugar were

added

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Food

Barley contains all eight essential amino acids. According to a recent study,

eating whole grain barley can regulate blood sugar for up to 10 hours after

consumption compared to white or even whole-grain wheat, which has a similar

glycemic index. Barley can also be used as a coffee substitute.

Hulled barley (or covered barley) is eaten after removing the inedible,

fibrous outer hull. Once removed, it is called dehulled barley (or pot barley or

scotch barley). Considered a whole grain, dehulled barley still has its bran and

germ making it a nutritious and popular health food. Pearl barley (or pearled

barley) is dehulled barley which has been steam processed further to remove the

bran. It may be polished, a process known as "pearling". Dehulled or pearl barley

may be processed into a variety of barley products, including flour, flakes similar

to oatmeal, and grits.

Barley-meal, a wholemeal barley flour which is lighter than wheatmeal but

darker in colour, is used in porridge and gruel in Scotland. Barley-meal gruel is

known as Sawiq in the Arab world. With a long history of cultivation in the

Middle East, barley is used in a wide range of traditional Arabic, Kurdish, Persian,

and Turkish foodstuffs including kashkak, kashk and murri. Barley soup is

traditionally eaten during Ramadan in Saudi Arabia. It is also used in soups and

stews in Eastern Europe. In Africa, where it is a traditional food plant, it has the

potential to improve nutrition, boost food security, foster rural development and

support sustainable land care.

The six row variety bere is cultivated in Orkney, Shetland, Caithness and

the Western Isles in the Scottish Highlands and islands. The grain is used to make

beremeal, used locally in bread, biscuits, and the traditional beremeal bannock.

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