With the dissolution of the agricultural projects that the Rockefeller Foundation (RF) was leading in China in 1940, it is in Mexico that a new testing ground for development programs based on the dissemination of new agronomic knowledge opens up. Science is seen as a key vector of progress, meant to replace the more political and social dimensions of the reforms needed to transform rural societies. The Mexican State sees, in turn, the possibility of accelerating the emergence of a modern science that would allow the depoliticization of the agrarian reform for technical solutions. In this perspective, Mexico has been a cradle of experimentation of the principles of the Green Revolution, hosting the Mexican Agricultural Program (MAP). It focused on the dissemination of high-yielding varieties and the coordination of extensive variety collection campaigns and breeding. We will review the results of this program through the scientific debates around the idea that poverty in rural areas was mainly due to the lack of technical knowledge. Today the failure of spreading innovations, like hybrid maize or GMOs, is still stigmatized. For some, it is a sign of an irrational attachment to certain habits, for others a laudable expression of political resistance against a modernization imposed from above. While remaining attentive to the political dimension underlying the idea of knowledge and technology transfer, we want to highlight other aspects. On the one hand, we identify more pragmatic reasons that motivate farmers’ choices; on the other hand, we show that scientific approaches were more contrasted than unanimous in the scientific and technical course undertaken in Mexico during the MAP years.