Plants having increased tolerance to herbicides

A plant or plant part comprising a polynucleotide encoding a mutated cellulose synthase (CESA) polypeptide, wherein the expression of said polynucleotide confers to the plant or plant part tolerance to CESA-inhibiting herbicides, wherein the mutated CESA polypeptide comprises on or more of the following motifs:

• i) Motif 1a:
• (SEQ ID NO:
• 78)
• [V/I][A/V]G[V/I/F][S/T][Y/D/N/A]A[V/I/L][N/S/G]
• [S/N]G[Y/F/E][Q/D/G/E/H][S/A]WG[P/A]L[F/M/L]G
• [K/R][L/V][F/L]F,
• wherein the amino acid at position 5, 16, and/or 17, within said motif is substituted by any other amino acid;
• ii) Motif 2a:
• (SEQ ID NO:
• 81)
• [V/L/I]W[S/A][V/A/I]LL[A/S]S[I/F/V][F/L][S/T]
• [L/V][L/M/V/I]WV[R/K][I/V][N/D]PF,
• wherein the amino acid at position 8 and/or 11 within said motif is substituted by any other amino acid.