Analysis of local limitations to maize yield under tropical conditions

Abstract

A method for the diagnosis of yield limitation in maize was tested. The test was based on a survey carried out in west Burkina-Faso, with a total of 437 farmers, over a period of 3 years. Data on weather, soil, farm, maize (cultural practices, and, on two plots per field, components of yield) were recorded. The diagnosis is based on analysis of yield components, compared with their potential values. 'Realisation indices' for different phases of growth are defined to quantify local stresses, and to locate them in relation to time. A treatment is proposed which allows us to distinguish long-lasting stresses (such as fertility) from transient or random stresses. In our conditions, long-lasting stresses appeared to be the most frequent. They result more from cultural practices than from environmental factors. The intensity of the random stresses also appeared to depend on cropping techniques. The method provided a satisfactory analysis of the different types of situations encountered in the survey. The diagnosis is limited by data available on the abiotic factors which are sources of stress.