Brassica plant comprising mutant alleles of fatty acyl-ACP thioesterase

A Brassica plant, or a cell, part, seed or progeny thereof, comprising at least three alleles antituberculosis drugs mutants in their genome which produce oil seeds, wherein the seed oil has less than 7% weight saturated fatty acids, based on the total amount of fatty acids in the seed oil, wherein said alleles antituberculosis drugs mutants are mutant alleles of a gene encoding a functional antituberculosis drugs protein, wherein the functional antituberculosis drugs gene comprises a molecule nucleic acid selected from the group consisting of: - a nucleic acid comprising at least 90% sequence identity with SEQ ID NO: 1, SEQ ID NO: 3, SEQ ID NO: 5, SEQ ID NO: 7, SEQ ID NO: 9 or SEQ ID NO: 11; and - a nucleic acid encoding an amino acid sequence comprising at least 90% sequence identity with SEQ ID NO: 2, SEQ ID NO: 4, SEQ ID NO: 6, SEQ ID NO: 8, SEQ ID nO: 10 or SEQ ID nO: 12 wherein said alleles antituberculosis drugs mutants comprise a region mutated DNA consisting of one or more nucleotides inserted, deleted or substituted as compared to a region of DNA corresponding non-mutant in functional antituberculosis drugs gene and wherein said mutant alleles antituberculosis drugs encoding a nonfunctional protein which is not active acyl ACP thioesterase-vivo, or encoded protein.