Cassava

New Potential for a Neglected Crop

James H. Cock

• Publisher: CRC Press
• Year: 2019
• eBook ISBN: 9780429724855
• Edition: 1
• Topic: Biological Sciences
• Subtopic: Biology
• Index: Biological Sciences

In this book, the author brings together the latest information on improved strains, modem production systems, better processing methods, innovations in storage and marketing, and the prospects for using cassava to produce fuel alcohol.

1
Cassava: The plant and its importance

Cassava is a starchy root crop that is grown almost entirely within the tropics. Although it is one of the most important food crops in tropical countries (see Table 1), it is little known elsewhere, and within the tropics, it is often considered to be a low-grade subsistence crop.

World production

In the 1979-1981 period, world production of cassava was about 120 million tons annually. Since the cassava root is about 65 percent water, that production level yields about 42 million tons of dry matter, which is equivalent, in energy terms, to 40 to 50 million tons of grain. Because much of the cassava grown is produced by small farmers in marginal agricultural areas and because most of it does not enter commercial marketing channels, it is difficult to obtain data on production. Food and Agriculture Organization (FAO) statistics are the best available guide to global production; however errors in the estimates for individual countries can be quite large. FAO figures for Brazilian production, for example, are much greater than estimates obtained from data in Brazil's agricultural census. From 1960 to 1980, world output of cassava rose at about the same rate as population. Almost all the gain has been due to expansion in planted area; yields have changed little.

Africa, though it has slightly more than half the world's cassava land, produces only 37 percent of the world crop. FAO estimates

Table 1
Staple crops as sources of calories in human diets in the tropics and worldwide (in billion kcal/day)

Crop	Tropics	World
Rice	924	2043
Sugar (cane and beet)	311	926
Maize	307	600
Cassava	172	178
Sorghum	147	208
Millet	128	204
Wheat	< 100^a	1877
Potato	54	434
Banana	32	44
Plantain	30	30
Sweet potato	30	208

Source: FAO, Food balance sheets 1975-1977 average (Rome, 1980).

^a Excluding Brazil, Mexico, and India, as the major wheat production zones of those countries are outside the tropics.

show that yields have been nearly constant at 6.4 t/ha in recent years, but between 1969-1971 and 1980, plantings increased from 5.8 million hectares to 7.3 million hectares, and annual production climbed from 39.4 million tons to 46.5 million tons. Zaire, Nigeria, and Tanzania are the major African cassava producers. Average yields in those countries range from 9 t/ha in Nigeria to less than 5 t/ha in Tanzania (see Table 2).

Asia accounts for only 27 percent of the world cassava area, but it produces 37 percent of the crop. Yields vary from less than 8 t/ha in Vietnam to over 16 t/ha in India. Increasing Asian output during the last 20 years has been due mainly to expansion in Thailand. Production in Thailand grew from less than 1 million tons in 1957 to 4 million tons in 1972 to an estimated 17.9 million tons in 1981. The second largest producer in Asia is Indonesia, which harvests over 13 million tons annually. Its land area in cassava had declined slightly in recent years, but gains in yields, which now average about 9.6 t/ha, have more than compensated for that decline. Another important

Table 2
Cassava production in Africa, Asia, and the Americas and selected countries, 1979-1981 average

	Area (million ha)	Yield (t/ha)	Production (million tons)
Africa	7.32	6.4	46.44
Zaire	1.82	6.8	12.40
Nigeria	1.18	9.2	10.83
Tanzania	0.94	4.9	4.60
Mozambique	0.60	4.6	2.78
Angola	0.13	14.2	1.85
Ghana	0.23	8.0	1.80
Madagascar	0.28	6.0	1.67
Uganda	0.41	3.4	1.39
Burundi	0.08	15.4	1.18
Cameroon	0.23	4.3	1.00
Central African Republic	0.33	3.0	0.99
Ivory Coast	0.22	3.5	0.75
Kenya	0.08	7.9	0.64
Congo	0.08	6.6	0.53
Togo	0.03	16.2	0.45
Asia	3.80	11.6	43.97
Thailand	1.00	14.4	14.54
Indonesia	1.42	9.6	13.67
India	0.35	16.7	5.90
Vietnam	0.46	7.3	3.38
China	0.24	13.0	3.06
Philippines	0.20	11.5	2.28
Sri Lanka	0.06	9.5	0.52
Malaysia	0.04	10.1	0.37
South America	2.55	11.7	29.90
Brazil	2.07	11.8	24.47
Colombia	0.21	9.8	2.07
Paraguay	0.13	14.9	1.97
Peru	0.03	11.4	0.40
Venezuela	0.04	9.5	0.36
Bolivia	0.02	12.4	0.22
Central America and the Caribbean	0.15	6.0	0.90

Source: FAO, Production yearbook (Rome, 1981).

Asian producer is India. Production has expanded markedly over the last few years in southwestern India, the primary growing area, due to increases in yields, which now are 16 to 17 t/ha. These high yields have been achieved despite soils that are very acid and infertile.

In the Western Hemisphere, Brazil dominates the production of cassava, accounting for four-fifths of the cassava in Latin America and one-fifth of world production. Cassava is grown throughout Brazil—in the hot, humid jungle of the Amazon basin, in the dry areas of t...

Table of contents

• Cover
• Half Title
• Series Page
• Title
• Copyright
• Contents
• List of Tables
• List of Figures
• Foreword
• Preface
• Introduction
• 1. Cassava: The plant and its importance
• 2. Food, feed, and industrial uses
• 3. Cassava production
• 4. Components of a new technology
• 5. New developments in post-harvest technology
• 6. Some case histories of cassava development
• 7. Development of national programs
• Appendix 1: Estimation of production costs of cassava and competitiveness with other energy sources
• Appendix 2: Where to get technical assistance and information on cassava
• Bibliography
• Index
• About the Book and Author