  In this work we present an analysis of flavor violating effects mediated by
color sextet scalars, which arise naturally in left-right symmetric gauge
theories based on SU(2)_L \times SU(2)_R \times SU(4)_C group. The sextets,
denoted here by \Delta_{dd}, Delta_{ud} and \Delta_{uu}, couple to
right--handed quarks. We delineate the constraints on these couplings arising
from meson--anti-meson transitions and flavor changing weak decays. The sextet
\Delta_{uu} mediates D^{0}-\bar{D}^{0} mixing via tree-level and box diagrams,
and also mediates D --> K pi, pi pi decays. The sextets \Delta_{ud} and
\Delta_{dd} mediate B_{d}^{0}-\bar{B}_{d}^{0}, B_{s}^{0}-\bar{B}_{s}^{0} and
K^{0}-\bar{K}^{0} mixings as well as rare B and D meson decays. Our analysis
shows that for coupling strengths of order 10^{-2}, the current experimental
data requires the mass of these color sextets to exceed several TeV. These
bounds are stronger than those obtained from direct LHC searches.
