Involved in the biosynthesis of the anti-fungal toxins colneleic acid and colnelenic acid. Can use (9S,10E,12Z)-9-hydroperoxy-10,12-octadecadienoic acid (9-HPOD) and (10E,12Z,15Z)-(9S)-9-hydroperoxyoctadeca-10,12,15-trienoic acid (9-HPOT) as substrates but has a very low activity with the corresponding 13-hydroperoxides. (9S)-hydroperoxy-(10E,12Z)-octadecadienoate = colneleate + H2O kcat is 890 sec(-1) for (9S,10E,12Z)-9-hydroperoxy-10,12-octadecadienoic acid. kcat is 500 sec(-1) for (10E,12Z,15Z)-(9S)-9-hydroperoxyoctadeca-10,12,15-trienoic acid. Expressed in roots. Detected in stems, but not in flower buds, petioles, cotyledons or leaves. Belongs to the cytochrome P450 family. 9-divinyl ether synthase subfamily.