Rice is intimately involved in the culture as well as
the food ways and economy of many Societies.
Rice is considered a gift of the gods, and it is treated
with reverence, and its cultivation is tied to elaborate rituals.
Chinese myth, by contrast, tells of rice being a gift
of animals rather than of gods.
Tradition holds that "the precious things are not pearls
and jade but the five grains", of which rice is first.
Though sufficient food is produced on global basis to
feed everyone, the pains of hunger continue to be a common experience
of many people in the world today especially in the developing countries
and under developed countries because of the rapid population growth.
Among the major cereals, rice is primarily staple food
for more than 2 billion people in Asia and hundreds of millions of people
in Africa and in Latin America.
Rice contains a large amount of starch, some proteins,
minerals and vitamins like E and B.
From our ancient scripts it is learnt that Indians knew
rice before the present era.
According to some earlier workers like Decandolle (1886)
and Watt (1862) the rice cultivation was originated in the South India.
Some other workers like Vavillov suggested that India
and Burma are centers of origin of cultivated rice.
The origins of rice have been debated for some time,
but the plant is of such antiquity that the precise time and place of
its first development will perhaps never be known.
It is certain, however, that The sub-species Indica
is mostly grown in India while in few pockets of Sikkim and in Himalayan
regions where cold climate exists the Japonica varieties are grown.
The classification of rice cultivated in India is as
follows,
Botanical Name:Oryzae sativa L
Family:
Gramineae
Species: Oryzae
Genus :
Sativa
Sub-species: Indica
Domestication of rice ranks as one of the most important
developments in history, for this grain has fed more people over a longer
period of time than has any other crop.
The earliest settlements might well have been near
the edge of the uplands, but on gently rolling topography and close
to small rivers that provided a reliable water supply.
The earliest agriculture was probable focused on plants
that reproduced vegetatively, but the seeds of easily shattering varieties
of wold rice such Oryja fatua may have found their way to the gardens
at an early date.
If these assumptions are correct, then domestication
most likely took place in the area of Korat or in some sheltered basin
area of northern Thailand, in one of the longitudinal valleys of Myanmar's
Shan Upland, in southwestern China, or in Assam.
Cultivated rices belong to two species, O.sativa and
O.glaberrima, of the two, O. sativa is by far the more widely utilized.
O. sativa is a complex group composed of two forms endemic
to Africa but not cultivated, and a third from, O. rufipogon, having
distinctive partitions into South Asian, Chinese, New Guinean, Australian,
and American forms.
The subdivision of O. sativa into these seven forms began
long ago and came about largely as a result of major tectonic events
and world wide climatic changes.
It is postulated, based on measurements by electrophoresis,
that the Australian form of O.sativa began to diverge from the main
forms about 15 million years ago.
At that time, during the Miocene, the Asian portion of
Gondwanaland collided with the Australia/New Guinea portion, creating
a land bridge across which O. sativa migrated.
Once the blocks separated, the Australian form was free
to follow an evolutionary path somewhat different from the followed
by the O.sativa on the mainland.
Divergence between the South Asian and Chinese forms,
the ancestors of what are commonly referred to today as indica and japonica
(or sinica) types, is believed to have commenced 2-3 million years ago.
At that time, migration of fauna across the proto-Himalaya
was still possible, and with the animals went wild rice.
The climate was suitable for rice even in what today
is Central Asia, and north China had almost ideal conditions.
Botanical evidence concerning the distribution of cultivated
species is based chiefly on the range and habitat of wold species that
are believed to have contributed to the cultivated forms.
The greatest variety of such rices is found in the zone
of monsoonal rainfall extending from eastern India through Myanmar,
Thailand, Laos, Northern Vietnam, and into southern China.
This diversity of species, including those considered
by may to have been involved in the original domestication process,
lends support to the argument for mainland southeast Asia as the heartland
of rice cultivation.
The earliest and most convincing archeological evidence
for domestication of rice in Southeast Asia was discovered by Wilhelm
G. Solheim II in 1966.
Piottery shards bearing the imprint of both grains and
husks of O.Sativa were discovered at Non Nok tha in the Korat area of
Thailand.
These remains have been confirmed by 14C and thermoluminescence
testing as dating from at least 4000 B.C.
Rice, an annual grass belongs to the genus Oryzae. There
are about twenty three species out of which only two species have been
known of their commercial value being used for cultivation.
These two species are Oryzae sativa (Asian rice) and
Oryzae glaberrima (African rice). The Oryzae sativa is the most commonly
grown species through out the world today while Oryzae glaberrima is
grown only in South Africa.
In Asia Oryzae sativa is differentiated into three sub
species based on geographical conditions viz., Indicia, Japonica and
Javanica.
Indica refers to the tropical and sub tropical varieties
grown throughout South and Southeast Asia and Southern China.
The variety Japonica is grown in temperate areas of Japan,
China and Korea, while Javanica varieties are grown along side of indicas
in Indonesia .
From an early beginning somewhere in the Asian arc, the
process of diffusion has carried. Rice in all directions until today
it is cultivated on every continent exceptAntarctica.
In this early hearth area, rice was grown in forest
clearing under a system of shifting cultivation. The crop was grown
by direct seeding and without standing water.
Rice was grown on "farms" under conditions only slightly
different from those to which wild rice was subject. A similar but independent
pattern of the incorporation of wild rices into an agricultural system
may well have taken place in one or more locations in Africa at approximately
the same time.
It was in china that the processes of puddling soil and
transplanting seedlings were likely refined. Both operations became
integral pats of rice farming and remain very widely practiced to this
day.
Transplanting, like puddling, provides the farmer with
the ability to better accommodate the rice crop to a finite water supply
by shortening the field duration (since seedlings are grown separately,
and a higher density) and adjusting the planting calendar.
With the development of puddling and transplanting, rice
became truly domesticated. In China, the history of rice valleys and
low-lying areas is longer that its history as a dryland crop.
In southeast Asia, by contrast, rice was originally produced
under dryland conditions in the uplands, and only recently did it come
to occupy the vast river deltas.
Migrant peoples from South china or perhaps northern
Vietnam carried the traditions of wetland rice cultivation to the Philippines
during the second millennium B.C. and deutero-Malays carried the practice
to Indonesia about 1500 B.c From china or Korea, the crop was introduced
to Japan no later than 100 B.C.
Movement to western India and to Sri Lanka was also accomplished
very early. The crop may well have been introduced to Greece and neighboring
areas of the Mediterranean by the returning members of Alexander the
Great 's expedition to India ca. 344-324 B.C. From a centre in Greece
and Sicily, rice spread gradually throughout the southern portions of
Europe and to a few locations in North Africa.
Interestingly enough, medical geographers in the 16th
century played an important role in limiting the adoption of rice as
a major crop in the Mediterranean area.
During the 16th and early 17th centuries, malaria was
a major disease in southern Europe, and it was believed to be spread
by the bad air (hence the origin of the name ) of swampy areas.
Major drainage projects were undertaken in southern
Italy, and wetland rice cultivation was discouraged in some regions.
In fact, it was actually forbidden on the outskirts of
a number of large towns. Such measures were a significant barrier to
the diffusion of rice in Europe.
Carbon dioxide has long been the prime suspect for the
green house effect and warming up of earth , but it is now known that,
methane traps 20 times more energy.
Its agreed that methane concentrations are increasing
at the rate of approximately 1% yr.
A major methane source, perhaps even the largest of all,
is flooded riceland. Not only do methane-producing bacteria thrive in
such an environment, but rice plants themselves act as gas vents, putting
greater-than-expected concentrations into the atmosphere.
The problem is, of course, magnified by the extension
of rice area, by the expansion of irrigation facilities, and especially
by the enlargement of double-cropped rice areas.
Rice fields are suspected of putting 115 million t of
methane into the atmosphere each year. This is at least equal to the
total production from all of the world's natural swamps and wetlands.
Is it possible that agricultural intensification is hastening environmental
degradation?
As a result of Europe's great Age of Exploration, new
lands to the west became available for exploitation.
Rice cultivation was introduced to the New World by early
European settlers. The Portugeuse carried it to Brazil, and the Spanish
introduced its cultivation to several locations in Central and South
America. The first record for North America dates from 168.
The crop may well have been carried to that area by slaves
brought from Madagascar. Early in the 18th century, rice spread to Louisiana,
but not until the 20th century was it produced in California's Sacramento
Valley.
The introduction in the latter area corresponded
almost exactly with the timing of the first successful crop in Australia's
New South Wales.
History
