Trial design and analysis for onfarm adaptive research: a 1988 maize trial in the Mono Province of Benin

On-farm Adaptive Research (OFAR) In an alftsol area In Southern Benin (Mono Province) started in 1986 with the introduction of a collaborative project of the Direction de la Recherche Agronomique (DRA) of Benin, the Royal Tropical Institute (KIT) Amsterdam, and the International Institute of Tropical Agriculture (IlTA) Nigeria. Major constraints to agricultural development are: • declining soil fertility caused by shorter fallows: • reduction in average farm size because of the Increase in rural population: • low resource productivity in food crop production due to the predominant use of manual labor (seasonal shortages) and the non-utilization of inputs such as fertilizers and pesticides; and • low risk-bearing capacity of farmers who are confronted with highly variable incomes from agriculture. The principal aim of the OFAR project was to intensify crop production through the introduction of new crop technologies while maintaining and/or improving the sustainability of agriculture. Initial on-farm testing and adaptation of technologies focused on the introduction of new plant material (maize, cowpea, groundnut), row planting, higher plant densities, and the application of chemical fertilizers. The results of 1986 and 1987 trials showed that the replacement of the first season local variety with the improved TZSR-W variety was economically viable. It out yielded the local variety at about 700 kg/ha, which was sufficient to cover the additional seed cost. Although farmers were impressed by this yield increase, they had doubts about the storage quality of the cobs. This observation was confirmed by results of a storage trial showing storage losses about twice as high as those in the local maize variety. The same trials indicated a significant fertilizer response to maize. but given the existing maize/fertilizer price rati, the application of fertilizer was for most farmers not economically attractive. However, when fertilizer application was combined with the improved variety, the overall package was economically viable