Light colored scalars and the up quarks phenomenology

A colored weak singlet scalar can accommodate the 2σ disagreement of the measured forward-backward asymmetry from the Standard model prediction in the production at the Tevatron. Such colored scalars appear in a class of grand unified theories. Their couplings to up quarks can be fully constrained using oscillation observables, as well as di-jet and single top production measurements at the Tevatron. After making predictions for the flavour changing neutral current transitions in the charm and top quark sectors, we discuss the impact of these constraints on the texture of the up-quark mass matrix within a class of grand unified models.