Abstract. We introduce common generalization of (double) Schubert, Grothendieck, Demazure, dual and stable Grothendieck polynomials, and Di Francesco-Zinn-Justin polynomials. Our approach is based on the study of algebraic and combinatorial properties of the reduced rectangular plactic algebra and associated Cauchy kernels.Key words: plactic monoid and reduced plactic algebras; nilCoxeter and idCoxeter algebras; Schubert, β-Grothendieck, key and (double) key-Grothendieck, and Di FrancescoZinn-Justin polynomials; Cauchy's type kernels and symmetric, totally symmetric plane partitions, and alternating sign matrices; noncrossing Dyck paths and (rectangular) Schubert polynomials; multi-parameter deformations of Genocchi numbers of the first and the second types; Gandhi-Dumont polynomials and (staircase) Schubert polynomials; double affine nilCoxeter algebras