This work questions the means of production of scientific knowledge by non-scientific authors through the analysis of the development of agronomic experiences performed in agricultural exploitations instead of experimental stations. It attempts to demonstrate that the objection to scientific practices may be developed within industrial models of extensive farming themselves. To that end, the idea is to follow the career and commitment of certain researches who have contributed -at farmers' request in Argentina and France and in connection with no-till farming technology- to the construction and promotion of agronomic experimentation devices alternative to the confined station model. This type of cooperation responds to personal initiatives, to the expression of professional careers and identities developed at the interface between science and extension. The chosen cases reflect the recurring tensions and debates that encourage agronomic research in many countries concerning the means of arranging the diversity of occupations and missions these imply among institutions and within its core.