Automorphisms and forms of toric quotients of homogeneous spaces

We compute the automorphism group of the quotient of a generalized Grassmannian $G/P$ by the action of a maximal torus of the semisimple group $G$. We classify the twisted forms of such quotients, that is, varieties isomorphic to these quotients over an algebraic closure of the base field. It is proved that all such forms are unirational.
Bibliography: 20 titles.