African rice: Oryza glaberrima

Africa rice: Oryza glaberrima

 A variety of Oryza glaberrima
Classification of Africa rice (Oryza glaberrima)
Kingdom  Plantae – Plants
Subkingdom  Tracheobionta – Vascular plants
Superdivision  Spermatophyta – Seed plants
Division  Magnoliophyta – Flowering plants
Class  Liliopsida – Monocotyledons
Subclass  Commelinidae
Order  Cyperales
Family  Poaceae – Grass family
Genus  Oryza L. – rice
Species  Oryza glaberrima Steud. – African rice


An Africa rice grain
A kind of Africa white rice
Oryza glaberrima, commonly known as African rice, is a domesticated  rice  species. African rice is believed to have been domesticated 2,000-3,000 years ago in the inland delta of the Upper Niger river, in what is now Mali. Its wild ancestor, which still grows wild in Africa, is Oryza barthii.
Oryza barthii is a wild rice grows in sub-Saharan Africa. It grows in deep water, seasonally flooded land, stagnant water, and slowly flowing water or pools. It is the progenitor of cultivated Oryza glaberrima, an African rice.
The Oryza glaberrima species is grown in West Africa, and shows several negative characteristics with respect to the Asian rice species O. sativa, such as shattering, brittle grain and poor milling quality. More importantly, it consistently shows lower yields than O. sativa, but African rice often shows more tolerance to fluctuations in water depth, iron toxicity, infertile soils, severe climatic conditions and human neglect, and exhibits better resistance to various pests and diseases, such as nematodes, rice yellow mottle virus and the parasitic plants Striga.
The African species of rice (O. glaberrima) was cultivated long before Europeans arrived in the continent.
At the present time, O. glaberrima is being replaced everywhere in West Africa by the Asian species, introduced into the continent by the Portuguese as early as the middle of the 16th century.
Some West African farmers, including the Jola of southern Senegal, still grow African rice for use in ritual contexts.
Recent agronomic advances now allow for gene transfer between the two species, thus creating hybrids that are better adapted, and higher yielding under adverse conditions, than either parent species.
There are only two species of cultivated rice in the world: Oryza glaberrima, or African rice, and Oryza sativa, or Asian rice. The two species of rice have recently been crossed, producing a promising hybrid.
Scientist from the Africa Rice Center managed to cross-breed African rice with Asian rice varieties to produce a interspecific cultivar called NERICA, which is an acronym for "New Rice for Africa".


Ancient History of the O. glaberrima Species

The rice of Africa (O. glaberrima) has a long and noteworthy history.
Native to sub-Saharan Africa, O. glaberrima is thought to have been domesticated from the wild ancestor Oryza barthii (formerly known as Oryza brevilugata) by peoples living in the floodplains at the bend of the Niger River some 2,000–3,000 years ago.
The two strains of O. sativa (O. japonica and O.indica) were domesticated  independently, both probably in China. It is also possible that Asian rice was domesticated in tropical Asia south of China, but evidence for this possibility is still lacking.
O. glaberrima was first domesticated in the Inland Delta of the Upper Niger River, in what is today Mali, ≈2,000 or 3,000 years ago. The species spread to two secondary centers of diversification, one in the coast of Gambia, Casamance, and Guinea Bissau, the other in the Guinea forest between Sierra Leone and the western Ivory Coast.
O. glaberrima was selected for at several different localities within the vast forest and savanna areas, where the wild ancestor species O. barthii grew and was harvested by ancient hunting–gathering human populations.
Whether one or several centers of African rice domestication existed, the fact remains that African rice was first cultivated many centuries before the first Europeans arrived on the West African coast.
The early Colonial history of O. glaberrima begins when the first Portuguese reached the West African coast and witnessed the cultivation of rice in the floodplains and marshes of the Upper Guinea Coast. In their accounts, spanning the second half of the 15th century and all of the 16th century, they mentioned the vast fields planted in rice by the local inhabitants and emphasized the important role this cereal played in the native diet.
To summarize, the Jola and their neighbors were certainly growing wet rice and using intensive techniques, such as diking to retain rainwater and transplanting, at the time they first encountered the Europeans.

Differences Between O. glaberrima and O. sativa

Slight morphological differences separate the two species of rice.
Generally speaking, African rice has small grains that are pear-shaped and have a red bran and an olive-to-black seedcoat, straight panicles that are simply branched, and short, rounded ligules. However, some Asian rice types also have pear-shaped grains with a red bran, and some African types have pointed ligules.
Other ecological characteristics of the two species may more important from the point of view of human selection potential. African O. glaberrima varieties have certain negative features with respect to the Asian O. sativa: the seed scatters easily, the grain is brittle and difficult to mill, and, most importantly, the yields are lower.
But the O. glaberrima types also offer distinct advantages: the plants have luxurious wide leaves that shade out weeds and the species is more resistant than its Asian cousin to diseases and pests.
Moreover, African rice is better at tolerating fluctuations in water depth, iron toxicity, infertile soils, severe climates, and human neglect. Some O. glaberrima types also mature faster than Asian types, making them important as emergency food. These characteristics have made it worthwhile to attempt to cross both species, a feat that that has recently met with considerable success.
Tragically, food production in sub-Saharan Africa is diminishing by 1% a year. Per capita food production in 1966–1968 averaged 119 kg per person per year. By 1982–1984, it had fallen to 98 kg per person per year, and by 1993 to 91 kg per person per year In 1999 it climbed slightly to 94 kg per person per year. As early as the end of the 1960s, population growth was outstripping the annual growth of agricultural production. Thus from 1965 to 1973, population grew by 2.7%, whereas agriculture grew by 2.4%; this relationship was 2.9% to 1.1% from 1973 to 1980, and 3.0% to 2.1% from 1980 to 1990 “Africa is moving rapidly toward a third decade of declining food production and increasing population growth”.
In the 1960s, many African farmers were producing enough rice to feed themselves. Since then, yearly imports have increased 8-fold to 4 million metric tons .
The situation in Senegal illustrates clearly this shift from self-sufficiency to dependence on the market. Before independence, Senegal was importing rice from Southeast Asia, and later Mali. But this rice was destined for the cities; most rural rice-producing areas like Lower Casamance were largely self-sufficient. Rice imports for Senegal increased steadily, from 100,000 tons in the early 1960s, to ≈300,000 tons in the early 1980s.
 In the 1992–1993 marketing year, the cereal import requirements for rice was 400,000 tons, or ≈57% of all cereal imports. This amount increased to >557,000 in 1998. The broken rice that is imported is sold to wholesalers in Dakar and other regions, but clandestine trade is very important, with Gambian rice being found in all markets in great quantity.

The Distribution of O. glaberrima.

In West Africa, rice is grown as the main staple crop by 10–15 million people living in societies that are distributed along the coast, from the Casamance in Senegal to the bend of the Bandama River in the Ivory Coast. In addition, rice is an important but not a dominant crop in the drier savanna zones from the Senegal River to Lake Chad. Rice is also grown today as a commercial crop in Ghana and Nigeria.
In the coastal area, where rice is a dominant subsistence crop, isolated pockets of O. glaberrima cultivation remain in Guinea Bissau, Guinea, Sierra Leone, and in the Casamance region of southern Senegal, the zone we are concerned with here.
Everywhere, however, O. glaberrima types are fast being replaced by the higher yielding O. sativa varieties. This phenomenon is documented below with respect to the Jola peoples of Casamance, who some decades ago planted numerous varieties of African rice but no longer do so. The discussion that follows documents the O. glaberrima types that Jola cultivated in the 1960s, the reasons why they were abandoned, and the cultural context in which they still survive.
Important regional differences exist in the gender division of labor, the dominance of upland versus floodplain cultivation, the ratio of transplanted to direct-seeded rice, and the role played by secondary and commercial crops. But everywhere in the Jola area, rice is the dominant subsistence crop. It is grown all over the countryside, in tidal zones recovered from the mangrove vegetation, inland freshwater valleys, and low plateaus. It is also cultivated in peri-urban zones around secondary cities such as Ziguinchor, the capital of the Casamance, and Bignona, a town north of the Casamance River.
The rice samples collected were then identified in 1966 by R. Portères, the renowned rice expert, who divided the sample into the two species and named their various subspecies and types.
In summary, 6 of 19 varieties, or nearly one-third of the rice that was grown in 1965 by the inhabitants of the Jipalom community, belonged to the African rice (O. glaberrima) species. Interviews with the elderly ladies of the community confirmed that in the not-too distant past they grew many more African rice varieties.
Without the slightest hesitation they could name at least ten O. glaberrima varieties that were no longer planted. It is also quite probable that further south, in the more intensive rice-growing zone south of the Casamance River, the Jola were growing an even higher number of O. glaberrima varieties than in Jipalom in the 1960s.
To this day, African rice varieties are known in Jipalom under the general terms “ajola” (from the Jola, their ethnic label), or “ecasay” (from Casamance), whereas types of the introduced Asian species are known as “amanding” rices, to indicate that they were brought in by the Manding peoples, a nation of traders with which the Jola have had protracted interactions through the centuries.
In Jipalom, it is the women who select the rice seed; it is they, and not the men, who can distinguish the different varieties
The cultural aspects that dominate Jola women's choice of which varieties to plant have to do with their taste, the ease with which they are pounded (or milled), and how they respond to cooking.
A Jola can usually tell the general region from which a particular variety comes, and how long it has been stored, by its taste. Rice varieties from the southern Jola area tend to be “sweeter” tasting, except when they have been stored for a long time in granaries placed on the ceiling of the cooking huts; rice thus stored acquires a smoky taste. Jola women also prefer longer-grained rice, which is easier to pound, and nonglutinous varieties that they say are easier to cook.
Curiously, they also reject the long-grained rice that United States aid agencies give to the Senegalese government to distribute in times of need. They say it has a “strange” taste, perhaps because it is milled by machine, and they are not used to it. In short, the preferences and patterns that the Jola articulate with respect to their preferred rice varieties reflect a wide range of reasoning, from ecological or environmental to cultural and, as we shall see, religious.

Old Varieties Disappear and New Ones Are Introduced

In the late 1960s, and for several ensuing decades, many sub-Saharan African countries, including Senegal, entered a drought-ridden period. This meteorological disaster was not confined to the dry zones of northern Senegal. It was acutely felt even in the wetter, more tropical region of Lower Casamance to the south. In Bignona, a town close to the Jipalom community, rainfall for the month of June 1968 was only one-third that of previous years.
August and September, crucial months when the rain-fed fields had to be tilled before transplanting, received <200 mm of rain each, compared with >500 mm the year before.
In fact, the mean precipitation for Bignona in the years 1968–1977 was insufficient, with 1,056.33 mm of rain, compared with 1,436.41 mm for the years 1958–1967. But drought years were not always in consecutive years. Whereas 1969 and 1970 had a satisfactory precipitation, 1971 and especially 1972 were deficit years. Rain gauges set up in the community of Sindian, very near to Jipalom, registered <1,000 mm in 14 of 20 years between 1973 and 1993. In 1980, the situation had been catastrophic, with 676 mm of rainfall falling in the entire year. Insofar as rice cultivation was concerned, the situation certainly qualified as an agricultural drought, when plants suffered seriously from lack of moisture.
Conditions improved somewhat in the years after 1993. For example, precipitation in the Sindian area was 1,310 mm in 1994 and 1,435 mm in 1999. But the mean precipitation all over the Lower Casamance during the last decades has been several hundred millimeters below what it had been in the decades preceding the late 1960s.
One of the marked changes brought about by the rainfall deficit was the loss of many of the old rice varieties as new, fast-growing types were introduced by extension agents from national research centers such as DERBAC (Projet de Developpement Rural de la Casamance), and foreign development schemes such as the Dutch-financed ILACO (International Land Development Consultants) project.
Thus, in 1989, only 13 varieties of rice were being grown in Jipalom, compared with 19 in 1965–1966. Of the 1989 varieties, three were old O. sativa varieties that had been around before, and the rest were new, fast-ripening O. sativa varieties that had been introduced in the preceding years. The inhabitants could name at least seven of the old O. sativa varieties that had been abandoned.
Interestingly, only 2% or 15% of the varieties grown belonged to the African O. glaberrima species. Therefore, there had been a notable loss of diversity in the rice varieties being grown twenty years after the drought began.
The loss of diversity was very marked in the agricultural year 1999–2000. In that year, only nine varieties of O. sativa were being grown in the village, and only one variety of the O. glaberrima species.
Although some African types mature rapidly, their relatively low yields and difficulty in pounding or milling discouraged farmers from growing them.

African O. glaberrima Varieties Survive in Ritual Context

In communities north of the Casamance River, such as Jipalom, the inhabitants converted to Islam beginning in the 1930s. South of the river, however, in the wetter, more intensive rice-growing regions west of Oussouye, in the lands located at the entrance of the Casamance River, the majority of the inhabitants have remained practitioners of the traditional awasena religion (from kawasen, to pour palm wine libations at the shrines).
 Here, traditions relate that the supreme deity, the rain “god” known as Emitai, gave “Diola rice” (O. glaberrima) to the ancestors. This rice carried a life-giving power that explained the ultimate origins of the land that Emitai had bestowed upon the inhabitants. For this reason, some varieties of O. glaberrima should always be planted, to preserve the link to the ancestors, and to Emitai, who sends rain.
This marshy terrain is crisscrossed by marigotsthat create small islands where the people live and cultivate their rice fields. Because many of the fields are bathed by brackish water, the inhabitants like to grow the glaberrima species, which is tolerant of salt-saturated soils. The main function of the ejonkin rice is ritual, to propitiate the rain-shrine called Husurah.
This important shrine must be propitiated with African rice; varieties of the Asian species cannot be used. Small quantities of cooked rice belonging to any O. glaberrima species, in this instance ejonkin, must be placed each year around the shrine to ask for abundant rains. The participants in the ritual, however, often eat cooked rice belonging to O. sativa varieties. Thus, what is eaten is kept separate from what is required in sacred rituals.
Moreover, it is said that O. glaberrima varieties are difficult to thresh using one's feet because grains are arranged in a row on the spine. And they are difficult to pound (i.e., mill) because the red bran cannot be easily removed, and are slow to cook.
It is doubtful, however, that in former days, those who grew and cooked rice found it necessary to remove the bran, or to boil the rice for a short period.
In any case, African rice is said be “heavier” on the stomach and hence better at quenching hunger. It also makes a good flour that is more aromatic and tastes better than the flour made from theO. sativa species. As a flour it can be consumed as a drink, as porridge, cooked as dumplings, or grilled over hot cinders.
To summarize, the ancient species of African rice survives in pockets of Lower Casamance, where the Jola employ it in sacred rites. This is a common occurrence. All over the world, old “traditional” cultivars are used in ceremonies to propitiate the spirits, for the link between crops and the ancestors is a fundamental pillar of most agrarian societies. The Mende peoples of Sierra Leone, for example, use African rice, soaked in palm oil, as a major component of their ritual sacrifices to the ancestor .

c- NERICA: The new rice for Africa

The new varieties, named “New Rice for Africa” (hence NERICA), are a cross between O. glaberrima and O. sativa. They combine the hardiness of the African species with the productivity of the Asian species. Scientists at the West African Rice Development Association (WARDA) succeeded in crossing the two species by employing embryo rescue techniques that ensure the crosses are fertile and mature successfully due to high levels of hybrid vigor .
 In doing so, they used seeds of African rice varieties that local farmers, many of them women from Guinea, grew in their fields, and incorporated them into gene banks. The farmers, in turn, provided information to the scientists about the traits that they most valued in the new hybrids.
NERICA varieties shade out weeds, are resistant to pests and droughts, grow in poor soils, and mature 30–50 days earlier than traditional varieties. Moreover, they produce 400 grains per plant (as opposed to 75–100 in the older varieties), contain 2% more proteins and, as a bonus, are said to taste like African rice.
The high productivity conferred on the NERICA strains by their Asian parents means that yields can be increased from the previous 1 ton per hectare to 1.5 tons without major inputs. With fertilizers and good care yields can double or even triple. Thus, the new rice holds great promise for a region in desperate need of decreasing hunger and increasing food security.
The enormous scientific efforts that produced NERICA will result in a “Green Revolution” in which nearly 1.7 million West African farmers will benefit from increased food security. It will help their countries save millions of dollars in rice imports. The basis for this success story is to be found in those West African farmers who continued to grow the ancient O. glaberrima varieties of rice despite the introduction of the new Asian species. Their knowledge, expertise, and continued adherence to their traditional rice provided the basis for experiments that resulted in the creation of a promising new hybrid. Thus, both cultural and ecological variables entered significantly into these developments.
1-Họ Hòa thảo – Wikipedia tiếng Việt-ọ_Hòa_thảo.
2-Poaceae - Wikipedia, the free encyclopedia .
5-Poaceae (Gramineae) - .

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