Results revealed a significant 51% reduction in patchouli alcohol content in CLSD-infected leaves, which was correlated with a 94% decrease in expression of the patchoulol synthase (PTS)-encoding gene (p < 0.01) and a 79% reduction in farnesyl pyrophosphate synthase (FPPS)-encoding gene expression (p < 0.05), both critical for terpenoid biosynthesis. The gene discussed is FDPS; the disease is craniolenticulosutural dysplasia.