  We discuss transformation of p-adic pseudodifferential operators (in the
one-dimensional and multidimensional cases) with respect to p-adic maps which
correspond to automorphisms of the tree of balls in the corresponding p-adic
spaces.
  In the dimension one we find a rule of transformation for pseudodifferential
operators. In particular we find the formula of pseudodifferentiation of a
composite function with respect to the Vladimirov p-adic fractional
differentiation operator. We describe the frame of wavelets for the group of
parabolic automorphisms of the tree of balls in the p-adic field.
  In many dimensions we introduce the group of mod p-affine transformations,
the family of pseudodifferential operators corresponding to
pseudodifferentiation along vector fields on the tree of balls in p-adic
miltidimensional space and obtain a rule of transformation of the introduced
pseudodifferential operators with respect to mod p-affine transformations.
