ABSTRACT
Low soil fertility and poor soil structure, poor seed, water shortages, extreme temperatures, lack of access to inputs and markets-all limit the capacity of the small farmer in the tropics and subtropics to produce food. The factors that limit food production on the world’s small farms are virtually unlimited in number and variety. National averages in Asia are often less than 3 hectares, as in the Philippines; or between 1 and 2 hectares, as in Bangladesh. Faced with the multiple limitations, each a formidable problem, agricultural development programs inevitably tend to concentrate their efforts on those few factors that seem most crucial to crop production and easiest to improve. The analysis of farming systems properly begins with the identification of significant interactions: of people with plants, plants with animals, plants with other plants. The aim of the process is to identify situations in which existing farm resources are inefficiently used.
