Cleaves the arabidiol side chain at C15 to form 14-apo-arabidiol and a side-chain fragment (PubMed:23570231, PubMed:25724638). Involved in the biosynthesis of the volatile homoterpene (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT) in roots. Involved in the production of DMNT by degrading the triterpene arabidiol. May be involved in the defense again the fungal root pathogen Pythium irregulare by producing DMNT (PubMed:25724638). Expressed in root stele, root cortex, root epidermis, root pericycle of the root hair zone, and quiescent center at the root meristematic zone. Induced by jasmonate. Belongs to the cytochrome P450 family.