The invention relates to a method of controlling or combating microbial organism by applying an antimicrobial peptide to the microbial organisms, wherein said antimicrobial peptide derived from Lilium ‘Stargazer’ glycine-rich protein 1. In addition, the present invention provides an antimicrobial composition comprising an antimicrobial peptide of the invention, an additional biocidal agent and pharmaceutically acceptable vehicles, excipients, diluents, and adjuvants.