Involved in the biosynthesis of homoterpenes, attractants of herbivores parasitoids and predators (e.g. predatory mites and parasitoid wasps) (PubMed:21334702). Catalyzes the conversion of the C20 (E,E)-geranyllinalool to C16-homoterpene 4,8,12-trimethyltrideca-1,3,7,11-tetraene (TMTT) of the C15 (E)-nerolidol to C11-homoterpene (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT); these volatile compounds are produced upon insect herbivore attack and emitted from flowers and vegetative tissues during herbivore feeding (PubMed:21088219). Required during resistance responses to the fungus Alternaria brassicae (PubMed:29271603). Prevents oviposition of the phloem-feeding insect cabbage whitefly (Aleyrodes proletella) (PubMed:26699853). (3S,6E)-nerolidol + O2 + reduced [NADPH--hemoprotein reductase] = (3E)-4,8-dimethylnona-1,3,7-triene + but-3-en-2-one + H(+) + 2 H2O + oxidized [NADPH--hemoprotein reductase] (6E,10E)-geranyllinalool + O2 + reduced [NADPH--hemoprotein reductase] = (3E,7E)-4,8,12-trimethyltrideca 1,3,7,11-tetraene + but-3-en-2-one + H(+) + 2 H2O + oxidized [NADPH--hemoprotein reductase] Secondary metabolite biosynthesis; terpenoid biosynthesis. Expressed in stems, flower peduncles, receptacle of developing and mature flowers and in stigma of mature opening flower buds. By wounding, upon insect feeding, by the fungal elicitor alamethicin and infection with the bacterial pathogen Pseudomonas syringae DC3000 (PubMed:21088219). Induced by the biosynthetic intermediate 8-hydroxy-7-keto-d-cadinene (C234), especially in synergy with the bacterial pathogen P.syringae pv. maculicola (Psm) (PubMed:30967019). No visible phenotype under normal growth conditions, but loss of TMTT production after alamethicin elicitation (PubMed:21088219). Enhanced susceptibility to the fungus Alternaria brassicae (PubMed:29271603). Increased oviposition rate of the phloem-feeding insect cabbage whitefly (Aleyrodes proletella) (PubMed:26699853). Belongs to the cytochrome P450 family.