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This article presents a calculation of the mean electromotive force arisingfrom general small-scale magnetohydrodynamical turbulence, within the frameworkof the second-order correlation approximation. With the goal of improvingunderstanding of the accretion disk dynamo, effects arising through small-scalemagnetic fluctuations, velocity gradients, density and turbulencestratification, and rotation, are included. The primary result, whichsupplements numerical findings, is that an off-diagonal turbulent resistivitydue to magnetic fluctuations can produce large-scale dynamo action -- themagnetic analogue of the "shear-current" effect. In addition, consideration of$\alpha$ effects in the stratified regions of disks gives the puzzling resultthat there is no strong prediction for a sign of $\alpha$, since the effectsdue to kinetic and magnetic fluctuations, as well as those due to shear androtation, are each of opposing signs and tend to cancel each other.

Electromotive force due to magnetohydrodynamic fluctuations in sheared rotating turbulence