THE STUDY OF AGRONOMIC PRACTICES AND MAIZE VARIETIES APPROPRIATE TO THE CIRCUMSTANCES OF SMALL FARMERS IN HIGHLAND ECUADOR.

摘要

An interdisciplinary team study was made to determine the practicality and value of acquiring detailed farming systems information as part of a program to develop agricultural innovations for small farmers in an area development project. This thesis reports on agronomic aspects and is based on complementary use of anthropological methods and field experiments on farms.;Experiments showed that earlier topping could reduce maize grain yield by 20% but produced fodder of a higher quality that was needed to supplement other forage sources on farms too small to produce specialist forage crops. An innovation based on early detasselling raised fodder protein content and should benefit specifically the group of farmers least favored by most current research. Differences found among introduced varieties of maize in their stover yield and tolerance to local defoliation practices would affect their adoption by different groups of small farmers.;Although socio-economic differences among small farmers needed to be taken into account in designing technology, conventional experiments precluded the active participation of all but the most favored farmers. A series of modifications made during a two-year period to the conduct of agronomic research changed the character of the program from one solely organized according to agronomists' perceptions to one in which representative small farmers could contribute their technical knowledge and in which existing farming systems were respected. Special features were the use of many single-replication sites superimposed on farmers' crops and the establishment of an informal, collaborative relationship between farmers and researchers who contributed their distinct skills to the design, testing and evaluation of innovations.;A study of maize variety adaptation and response to fertilizers showed that this organization of experiments also successfully sampled the wide range of environmental and cropping system variation that existed within the major ecological zones used for area stratification. For example, an introduced early maize variety responded well to the use of fertilizer only on deep, moist soils sheltered from the prevailing wind, and yielded as well as the late-maturing local variety only where sandy soils and drought curtailed the growing season.;Farmers' production practices were generally shown to be rational and to be more finely adapted to small-scale ecological variation than had been suspected from an agroeconomic survey by questionnaire. Small farmers' production strategies also varied according to access to resources, with important implications for the development of appropriate innovations. Resource-poor farmers were more interested in restoring crop yields to former levels, particularly by controlling pests and diseases, than in raising yield potentials through the use of fertilizer-responsive varieties. This group also made more use of interactions between crop and animal enterprises, for example earlier topping of maize plants for green fodder.;A study of the feasibility of extending the practice of double cropping by introducing early crop varieties suggested that subsistence farmers would prefer adding an early pea variety in sequence with their late maize crop. The alternative of changing to an early maize variety would usually reduce total production of maize, but could be acceptable to more commercially oriented farmers.