Cassava is a perennial woody shrub with an edible root, which grows in tropical and subtropical areas of the world. Cassava originated from tropical America and was first introduced into Africa in the Congo basin by the Portuguese around 1558. Today, it is a dietary staple in much of tropical Africa.
It is rich in carbohydrates, calcium, vitamins B and C, and essential minerals. However, nutrient composition differs according to variety and age of the harvested crop, and soil conditions, climate, and other environmental factors during cultivation.
Apart from food, cassava is very versatile and its derivatives and starch are applicable in many types of products such as foods, confectionery, sweeteners, glues, plywood, textiles, paper, biodegradable products, monosodium glutamate, and drugs. Cassava chips and pellets are used in animal feed and alcohol production.
Cassava production depends on a supply of quality stem cuttings. The multiplication rate of planting materials is very low compared to grain crops, which are propagated by true seeds. In addition, cassava stem cuttings are bulky and highly perishable as they dry up within a few days.
Many varieties contain a substance called cyanide that can make the crop toxic if inadequately processed. Various processing methods, such as grating, sun drying, and fermenting, are used to reduce the cyanide content.
Disease and constraints
IITA's biological control program resulted in a 95% reduction in cassava mealybug damage and a 50% reduction in damage caused by the cassava green mite.
Post-harvest strategies include the development of effective and simple machines and tools that reduce processing time and labor, and production losses. With these machines, losses can be reduced by 50% and labor by 75%.
During the past three decades, IITA has trained more than 9000 researchers and technicians in ten African countries in processing and in new uses for high quality cassava flour (HQCF). As a result, the private sector in Madagascar, Nigeria, Tanzania, and Uganda have begun using HQCF as a raw material for processing secondary products such as biscuits and noodles.
SciDevNet: Cassava varieties show promise against deadly diseases
12 September 2016
“The environment where cassava is grown varies greatly in soil fertility and altitude,” says Edward Kanju, a cassava breeder with the International Institute of Tropical Agriculture (IITA) in Dar-es-Salaam, Tanzania, in an interview with SciDev.Net last month (9 August). “We aim to identify the best suitable varieties for specific environments.” Read more.