The ‘‘system of rice intensification’’ (SRI) that evolved in the 1980s and 1990s in Madagascar
permits resource-limited farmers to realise yields of up to 15 t of paddy/hectare on
infertile soils, with greatly reduced rates of irrigation and without external inputs. This paper
reviews the plant physiological and bio-ecological factors associated with agronomic practices
that could explain the extraordinary yields in terms of synergies resulting from the judicious
management of the major crop production factors: time, space, water, plant nutrients and
labour. The findings underscore the importance of integrated and interdisciplinary research,
combining strategic and adaptive (on-farm participatory) approaches that explore and link
bio-physical and socio-economic factors in crop production. Such approaches would permit
to unlock currently untapped production potentials of rice and other major cereal grain crops,
without extra costs to farmers or to the environment.