We show that at the onset of a cyclic fold bifurcation, a birhythmic medium
composed of glycolytic oscillators displays turbulent dynamics. By computing
the largest Lyapunov exponent, the spatial correlation function, and the
average transient lifetime, we classify it as a weak turbulence with transient
nature. Virtual heterogeneities generating unstable fast oscillations are the
mechanism of the transient turbulence. In the presence of wavenumber
instability, unstable oscillations can be reinjected leading to stationary
turbulence. We also find similar turbulence in a cell cycle model. These
findings suggest that weak turbulence may be universal in biochemical
birhythmic media exhibiting cyclic fold bifurcations.Comment: 14 pages 10 figure