Fantastic yields in the system of rice intensification: fact or fallacy?

The combination of natural resources, genes, weather and management systems largely determines maximum crop yields. Recently, one of those elements was portrayed as the key to releasing hitherto unrecognized, but significant, untapped growth potential in rice. That element, the system of rice intensification (SRI), is an unconventional management system developed in Madagascar, where it was reported to increase rice yields to 'fantastic' levels. To investigate the general potency of the SRI, we conducted experiments in three locations in China comparing yields in conventional and SRI management systems. In addition, we used a theoretical model to predict maximum yields and compared those with reported yields for various locations, including China and Madagascar. Our results imply that the SRI has no inherent advantage over the conventional system and that the original reports of extraordinary high yields are likely to be the consequence of error. (C) 2004 Elsevier B.V. All rights reserved.