Abstract
Given a degree 1 cohomology class u on a closed manifold M, we define a Novikov fundamental group associated with u, generalizing the usual fundamental group in the same spirit as Novikov homology generalizes Morse homology to the case of non exact 1-forms. As an application, lower bounds for the minimal number of indexes 1 and 2 critical points of Morse closed 1-forms are obtained, that are different in nature from those derived from the Novikov homology. [GRAPHICS]