A chemically-inducible plant gene expression cassette comprising
    a first promoter operatively linked to the alcR regulator sequence obtainable from Aspergillus nidulans which encodes the AlcR regulator protein, and
    an inducible promoter operatively linked to a target gene, the inducible promoter being activated by the regulator protein in the presence of an effective exogenous inducer whereby application of the inducer causes expression of the target gene.

A method for controlling plant gene expression comprising
    transforming a plant cell with a chemically-inducible plant gene expression cassette which has
        a first promoter operatively linked to the alcR regulator sequence obtainable from Aspergillus nidulans which encodes the AlcR regulator protein, and
        an inducible promoter operatively linked to a target gene, the inducible promoter being activated by the regulator protein in the presence of an effective exogenous inducer whereby application of the inducer causes expression of the target gene.

A chimeric promoter comprising
    an upstream region containing a promoter regulatory sequence obtainable from the alcA gene promoter of Aspergillus nidulans and
    a downstream region containing a transcription initiation sequence, characterised in that said upstream and downstream regions are heterologous, the promoter is chemically inducible and the transcription initiation sequence is obtainable from the core promoter region of a promoter which is active in plant cells.

A plant cell which contains stably integrated into its genome a gene expression cassette, said gene expression cassette comprising
    a first promoter operatively linked to a sequence comprising an alcR coding sequence from Aspergillus nidulans and which encodes an ALCR regulator protein, and
    an inducible promoter from an ALCR-activatable gene, which gene is the alcA gene from Aspergillus nidulans, operatively linked to a target gene, said inducible promoter being activated by the ALCR regulator protein in the presence of an alcohol and/or ketone inducer, so that application of a sufficient amount of a suitable inducer causes expression of the target gene.

A method for controlling plant gene expression comprising
    transforming a plant cell with a chemically-inducible gene expression cassette which has
        a first promoter operatively linked to a sequence comprising an alcR coding sequence from Aspergillus nidulans, and which encodes an ALCR regulator protein, and
        an inducible promoter from an ALCR-activatable gene, which gene is the alcA gene from Aspergillus nidulans, operatively linked to a target gene, said inducible promoter being activated by the ALCR regulator protein in the presence of an alcohol and/or ketone inducer, so that application of a sufficient amount of a suitable inducer causes expression of the target gene.

A plant cell containing a chimeric promoter operatively linked to a target gene, said chimeric promoter comprising
    an upstream region containing a promoter from an ALCR-activatable alcA gene from Aspergillus nidulans and     a downstream region containing a transcription initiation sequence, wherein the upstream region and the downstream region are heterologous and the chimeric promoter is inducible by an alcohol and/or ketone, so that application of a sufficient amount of a suitable inducer, in the presence of the ALCR regulator protein encoded by the alcR gene from Aspergillus nidulans, causes expression of the target gene.