Sep 5, 2012

Cassava News 102

FOOD CROPS Cassava News 102 (Tin Mới Cây Sắn)
KM419 Cassava Variety, Photo by NgocphuongNam
FAO   Agriculture   Cassava : An Overview

Why cassava?

Cassava (Manihot esculenta Crantz) is the third most important source of calories in the tropics, after rice and maize. Millions of people depend on cassava in Africa, Asia and Latin America. It is grown by poor farmers, many of them women, often on marginal land. For those people and their families, cassava is vital for both food security and income generation.
But cassava is often seen as a poor cousin in the world's family of staple crops. While admirably tolerant to drought and productive on poor soils, this hardy tropical root seems unsuited to modern farming. First, it is usually propagated vegetatively from stem cuttings that do not store well and are costly to cut and handle. Vegetative reproduction also means the rate of multiplication of new, improved varieties is slow, retarding their adoption. Harvesting cassava is labour-intensive, and its roots are bulky and highly perishable.
Little wonder, therefore, that cassava is usually grown by poor farmers in marginal areas - and even there, it faces increasing competition as cereals are further improved to adapt them to local conditions. In fact, far less research and development have been devoted to cassava than to rice, maize and wheat. This lack of scientific interest has contributed to highly uneven cultivation and processing methods, and cassava products that often are of poor quality.
The Global Cassava Development Strategy, launched in Rome in 2000, seeks to change all that. At a forum at FAO headquarters, some 80 agricultural experts from 22 countries were asked whether cassava had the potential not only to meet the food security needs of the estimated 500 million farmers who grow it, but to provide a key to rural industrial development and higher incomes for producers, processors and traders.
The forum's conclusion: cassava could become the raw material base for an array of processed products that will effectively increase demand for cassava and contribute to agricultural transformation and economic growth in developing countries.

Global Cassava Development Strategy


FAO's rationale for developing a Global Cassava Development Strategy is the belief that the crop will contribute to the economic development of cassava producers and processers and the well-being of numerous disadvantaged communities and individuals around the world.
The broad agro-ecological adaptability of cassava, and its ability to produce reasonable yields where most crops cannot, make it the basis for food security at household level and an important source of dietary energy. The crop is an essential part of the diet of more than half a billion people and provides a livelihood for millions of farmers, processors and traders worldwide.
Despite its importance as a staple crop and industrial raw material, and its contribution to fighting hunger and poverty in developing countries, cassava has often been neglected in agricultural development policies and has received considerably less emphasis in genetic improvement and biotechnology than most other major food crops.
The Global Strategy is the result of the visionary efforts, dating from 1996, of a number of individuals and institutions that have spurred renewed interest in cassava and its links to the development process. The revival of interest in cassava can be traced back to May 1996, when a meeting called by the International Fund for Agricultural Development (IFAD) decided to form a Task Force to spearhead the development of a strategy for cassava.
The goal of the Task Force was to realize the shared vision for cassava and move it closer to action and reality. In 1998, international experts prepared a Global Cassava Development Strategy (GCDS) document. The GCDS was officially endorsed by stakeholders at a Validation Forum held at the headquarters of Food and Agriculture Organization of the United Nations (FAO) in Rome in April 2000. An implementation plan was also adopted.
A coordination group composed of representatives of the organizations playing an active role in the development and endorsement of the Strategy will be responsible for the facilitation of the coordination of the Strategy.


The Implementation Plan draws on the principles outlined in the strategy document and takes into consideration the priorities established by representatives of the public and private sectors during the various consultation meetings held in Africa, Asia and Latin America and the Caribbean. The Plan also reflects the discussions and conclusions reached by the participants in the GCDS Validation Forum.
It was agreed at the Forum that FAO, in its position as an international organization, supported by a large number of Member Governments, has a key facilitation role to play in the implementation of the Strategy. In the first place, FAO will publish the report of the Validation Forum using funds made available by IFAD. FAO will also be responsible for the maintenance, updating and enhancement of the GCDS Web site, which is already accessible through FAO's Web page. It was acknowledged, however, that commitments were also required from other organizations to assist in promoting and coordinating the implementation of the Strategy.


To facilitate the implementation of the Strategy at global, regional and national levels, coordination was essential to avoid duplication, promote cooperative activities and ensure that benefits of the strategy could be shared widely. A coordination group was therefore created by representatives of organizations that played an active role in the development of the Strategy.
The Coordination Group on the Global Cassava Development Strategy is composed mainly of representatives of organizations that played an active role in the development of the Strategy. There are three categories for membership of the Group:
  • Representatives of the organizations that played an active role in the development and endorsement of the Strategy (IFAD, FAO, CIAT, CIRAD, IITA, NRI).
  • Representatives of Agricultural Research Organizations (AROs) and advanced laboratories, National Agricultural Research System (NARS), development organizations and private sector.
  • Representatives of financing and donor agencies.
The Group has the power to broaden its constituency and co-opt other members whenever necessary. The secretariat for the Group is located at the Crop and Grassland Service (AGPC) of FAO, Rome, Italy. The objective of the Group is to promote the Strategy and promote cassava by stimulating its production, processing, utilization and marketing. Coordination basically involves the following:
  • Making available all documentation related to the GCDS.
  • A careful monitoring of cassava research and development efforts.
  • Coordination of efforts of regional networks to optimize cross-fertilization and economies of scale.
  • Provision of advice for the implementation of the GDCS at national and regional levels.
  • Responding to outside demand of information on cassava.
  • Contact us

Research and development

GCDS provides information on strategic research and development activities undertaken by its partners in areas related to genetic improvement and biotechnology, improved production systems, post-harvest and processing, environmental considerations, institutional development and policy research. GCDS also focuses on supporting the development of action plans on global cassava improvement, global cassava post harvest and global cassava marketing. In addition, GCDS provides information on some key national, regional and global projects on cassava research and development.

Genetic improvement and biotechnology

GCDS suggests that genetic improvement of cassava be related to the use of cassava. Thus the "best" cassava is no longer the highest yielding cassava, or the cassava with the greatest resistance, unless it is the "best" cassava to use for the production of a specific product.
Conventional breeding efforts have attempted to address many of the constraints facing cassava productivity, but with limited success. Progress has been slow, because of the crop's complex genetic makeup, which makes it difficult to breed efficiently. Biotechnology provides new tools for overcoming some of the problems that hindered cassava improvement. New technologies have the potential to make cassava much more productive, nutritious and profitable to grow.

Cassava genetic resources

With the increasing importance worldwide of cassava for human consumption, animal feed and industrial applications, there will be an increasing need for a wide range of genetic resources (e.g. cassava germplasm, wild Manihot and related species) to develop cultivars having specific characteristics and for adaptation to different ecologies. To this end cassava biodiversity deserves international support and cooperation in its collection, conservation, study and use.
Conserving, maintaining and safe duplication of cassava genetic resources using a combination of available conservation methods will facilitate the:
  • safeguarding of important cassava-related germplasm from loss due to environment degradation;
  • study of relatedness of the species of the Manihot genus;
  • availability of a germplasm pool for screening for potential important agronomic traits (i.e. disease resistance, post-harvest characteristics, nutritional qualities, apomixis);
  • availability of a source of genes for transfer of beneficial traits to farmer-preferred cassava cultivars.
There are some gaps in the existing ex situ collection, with respect to the representation of genetic diversity from many geographical areas. Few collections of wild relatives of cassava have been assembled and conserved in ex situ genebanks.
Due to the destruction of natural habits where wild relatives of cassava are growing and also due to the trend in the abandonment of old traditional cassava cultivars by farmers adopting improved varieties, there is a need to collect the cassava biodiversity not represented in the existing collections for ex situ conservation. Concurrently, germplasm characterization using agrobotanical descriptors and molecular markers should be intensified to assist in the selection of core collections and the elimination of duplicates, thus increasing the efficiency of germplasm management and its use.
Appropriate strategies for in situ or on-farm conservation of cassava genetic resources should be developed and encouraged to complement ex situ conservation. Policies governing the areas for the conservation of cassava biodiversity and its use and access should be well articulated to ensure that the genetic resources are accessible to the users. GCDS will support the effort to reduce varietal and genetic resources erosion, develop better tools and harmonize protocols and methodologies for characterization of cassava genetic diversity. 


Most publications are available electronically in full-text in either html or pdf format.

The strategy

The Global Cassava Development Strategy and Implementation Plan (FAO/IFAD, 2001)


The world cassava economy - facts, trends and outlook (FAO, 2000)

Regional/country studies


A review of cassava in Africa with country case studies on Nigeria, Ghana, the United Republic of Tanzania, Uganda and Benin (FAO/IFAD, 2005)


A review of cassava in Asia with country case studies on Thailand and Viet Nam (FAO/IFAD, 2001)

Latin America/Caribbean

A review of cassava in Latin America and the Caribbean with country case studies on Brazil and Colombia (FAO/IFAD, 2004)


Strategic environmental assessment - the impact of cassava production and processing on the environment and biodiversity (FAO, 2001)


Global cassava market study (FAO, 2004)

FAO has a key facilitation role to play in the implementation of the Strategy


The secretariat of the Global Cassava Development Strategy Coordination Group is located in the Crop and Grassland Service (AGPC) of FAO, Rome, Italy. Contact:
NeBambi Lutaladio
Agricultural Officer (Root and Tubers)
Crop and Grassland Service
Food and Agriculture Organization of the United Nations
Viale delle Terme di Caracalla
00153 Rome, Italy
tel.: (39) 0657054233

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