ABSTRACT
Cassava (Manihot esculenta Crantz) is one of the most important cal orie-producing crops in the tropics. It is efficient in carbohydrate pro
duction, adapted to a wide range of environments, and tolerant to drought and acid soils (Jones, 1959; Rogers and Appan, 1970; Kawano et al., 1978; Cock, 1982). Throughout the tropics, small farmers grow cassava in areas with poorer soils using traditional methods of cultiva tion. The major portion of the economic product, the root, is consumed as human food after varying degrees of processing. An estimated 70 million people obtain more than 2100 J d-1(500 Kcal/d) from cassava, and more than 500 million people consume more than 420 J d~'(100 Kcal/d) in the form of cassava throughout the tropics (Cock, 1985a). More recently it has been used increasingly for animal feed and indus trial starch and is becoming an important source of cash income to a large number of small farmers (Lynam, 1986; Bottema and Henry, 1992).
