Hybrid excitations of the QCD string with quarks

The model for consituent glue is presented starting from the perturbation theory in nonperturbative QCD vacuum. The Green function is constructed for a system containing a qq pair and a gluon propagating in the vacuum background field, and the Hamiltonian approach to the problem is formulated. The masses of lowest qqg hybrids with light quarks are evaluated, and the implication of the results for the spectroscopy of exotic states is discussed.