The “omics” technologies—genomics, transcriptomics, proteomics, and metabolomics—are at the forefront of discovery in modern plant science and systems biology. In contrast to the rather static genome, however, the metabolome and the products measured in it are very dynamic. In science, metabolome refers to the totality of all small molecules, also known as metabolites, in a biological cell, tissue or organism. Their concentration generally fluctuates greatly, both spatially and temporally.