A method and system is provided for generating excreted gene products in a plant which includes generating a nucleic acid fusion construct comprising a phylloplanin promoter and a selected non-phylloplanin nucleic acid sequence whose transcription product is to be expressed and delivered to an aerial surface of a plant. The method includes transfecting plant cells with the nucleic acid fusion construct and allowing the plant cells to express the non-phylloplanin nucleic acid sequence transcription product which is then excreted from the plant cells to the aerial surfaces.