Turbulent transport of a heliotron/torsatron is investigated near the radius where the pitch of the magnetic field line is minimum or maximum. The current diffusive interchange mode turbulence is analysed. The curvature of the pitch of the magnetic field line dictates the level of the turbulence and the turbulent transport. The enhanced turbulence and the suppression of the pressure gradient are shown to occur in the vicinity of the radius where the magnetic shear vanishes. The dependence of the nonlinear decorrelation rate of the turbulence on the pressure gradient is found to be independent of the magnitude of the shear, γNL ≃ G01/2 (G0 being the normalized pressure gradient multiplied by the gradient of the magnetic field).
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