Scientific Evidence and the Smallholder Farmer: Conservation Agriculture Research, Inference Space and Quality of Science.

Systematic reviews (SR) with statistical meta-analysis are the standard of practice for translating science into evidence-based management and policy in many disciplines. To date, agriculture has been slow to adopt the methodology despite a long-standing commitment to Extension education founded on recommendation derivation from the latest research. Some have questioned the applicability of the approach when site-, soil- and culture-specific considerations for a given farmer/farm are likely to differ in one or more key ways from those of the empirical studies contributing to a SR synthesis. Such concerns are greatest for smallholder farmers as the preponderance of published research on a topic is likely to have occurred in the context of intensive agriculture in developed countries where investment in agronomic research has been a persistent priority. This presentation focuses on the question of inference space, how it is characterized, and how SR can be used to improve both the general quality of science and its relevance to smallholder farmers. The discussion will draw on a recently-completed case study of the impacts of conservation agriculture on yields of staple crops in sub-Saharan Africa and South Asia. Additional insights emerging from completed and ongoing reviews of two CGIAR Research Programs will be integrated. The CGIAR programs typify trends in research for development and pursue evidence-based sustainable or “ecological” intensification as their core strategy for reducing yield gaps on smallholder farms. The major premise of the strategy is that single, panacea interventions that are universal in efficacy do not exist; both the entry points for interventions and the interventions themselves will be unique and must be locally tailored to optimize outcomes. The role of SR in a knowledge translation framework for achieving sustainable intensification goals will be analyzed and lessons-learned on various aspects of quality of science will be presented.