ABSTRACT
Irrigated agriculture has a long history in Asia and many farmers are familiar with it. Consequently, sequential cropping systems are often adopted relatively quickly after irrigation is introduced. Because output under sequential cropping is far greater than under mono-cropping, irrigation is often economically feasible in Asia. In Africa there is considerable scope for increasing agricultural productivity by opening up new land and increasing the yield of present rainfed agriculture. Irrigation has, therefore, often proved to be only marginally economical in Africa. The cropping calendar and the calendar of social events are often closely interlinked. When intensive multiple cropping systems are introduced, extra crops should normally be raised which interferes with local customs and may lead to social tensions. Like other development initiatives, attempts to develop multiple cropping will only succeed if the local socio-economic conditions and constraints are taken fully into account.
