Cassava (Manihot esculenta)

Description

Cassava, a perennial shrub, produces a high yield of tuberous roots in 6 months to 3 years after planting.

Originating in Central and South America, cassava spread rapidly and arrived on the west coast of Africa via the Gulf of Benin and the River Congo at the end of the sixteenth century and on the east coast via the Reunion Island, Madagascar, and Zanzibar at the end of the eighteenth century. The crop then spread inland from both sides. By the early 1800s cassava arrived in India, but controlled breeding did not begin until the 1920s.

Today, peasant farmers mostly grow cassava. For many of these farmers, it is the primary staple. They also use it as a cash crop to produce industrial starches, tapioca, and livestock feeds. Cassava adapts to elevations ranging from sea level to 2000 meters. It has the ability to withstand poor environmental conditions, such as low rainfall and infertile soil.

Statistics

World production for 2004 was estimated at 204,819,995 metric tons.
Production in Asia during the same period was 60,492,789 metric tons and in Africa 108,974,574 metric tons.

Area harvested in 2004:
World: 18,051,574 hectares
Brazil: 1,754,875 hectares
Congo: 1,842,559 hectares
Indonesia: 1,255,805 hectares
Nigeria: 3,531,000 hectares
Mozambque: 1,068,500 hectares

How is Cassava Used? What is its Nutritional Value?

Cassava provides a major source of calories for poor families, because of its high starch content. With minimum maintenance, the farmers can dig up the starchy root of the cassava and eat it 6 months to 3 years after planting. Thus, people can cultivate cassava during times of war or natural disaster when no other food is available. In Africa, people also eat the leaves of the cassava as a green vegetable, which provide a cheap and rich source of protein and vitamins A and B. In Southeast Asia and Latin America, cassava has also taken on an economic role. Various industries use it as a binding agent, because it is an inexpensive source of starch. Cassava starch is used in the production of paper and textiles and as monosodium glutamate (MSG), an important flavoring agent in Asian cooking. In Africa, cassava is beginning to be used in partial substitution for wheat flour, thus providing income to resource-poor farmers and saving foreign exchange for national governments.

Center's Work on Cassava:

Scientists at two CGIAR research centers IITA and CIAT have developed elite varieties of cassava with improved qualities. IITA has discovered spontaneous polyploids in cassava, which are characterized by enormous vigor and variation in form and structure. Selections from triploids "super cassava" have doubled the yields of existing improved varieties with normal chromosome numbers.

IITA has also introduced to Africa a wider genetic base for cassava improvement, focusing on materials with resistance to mites, mealybugs, cassava bacterial blight, tolerance to drought, low cyanogen potential, and good cooking quality. IITA manages two root crops research networks in eastern and southern Africa focusing on cassava (the East African Root Crops Research Network and the Southern Africa Root Crops Research Network) to take new agricultural technologies right down to the farmers. It has assisted with identifying, evaluating, and shipping natural enemies to control the cassava mealybug and cassava green mite.

Together, IITA and CIAT launched a famous biological control campaign of the mealybug and are cooperating with the International Fund for Agricultural Development in the formulation of a global development strategy for cassava.

Sources:

FAOSTAT. PRODSTAT.

Technical Advisory Committee: CGIAR Priorities and Strategies for Resource Allocation during 1998-2000.
April 1997.

Evolution of Crop Plants.
N.W. Simmonds. 1979.

25 Years of Food and Agriculture Improvement in Developing Countries.
CGIAR Secretariat.