Cytochrome P450 metabolizing both 13- and 9-hydroperoxides of linoleic and linolenic acids, but with a marked preference for 9-hydroperoxy fatty acids (PubMed:12351632, PubMed:18780387). Has no activity toward 13S-hydroperoxy-9(Z),11(E),15(Z)-octadecatrienoic acid (13-HPOT) (PubMed:18780387). Catalyzes not only the synthesis of allene oxide, but also its hydrolysis and cyclization (PubMed:18780387). The first step is the synthesis of (12Z)-9,10-epoxyoctadeca-10,12-dienoic acid (9,10-EOD) and the final products are (9R)-alpha-ketol and the racemic cis-10-oxo-11-phytoenoic acid (PubMed:18780387). The cyclase activity possesses regiospecificity and (9Z)-12,13-epoxyoctadeca-9,11-dienoic acid (12,13-EOD) is significantly less efficient as a substrate for cyclopentenone production than 9,10-EOD (PubMed:18780387). Has no hydroperoxide lyase activity (PubMed:12351632). May play a defensive role against soil-borne pests that affect roots or juvenile tissues as they emerge from the germinating seed (PubMed:12351632). (13S)-hydroperoxy-(9Z,11E,15Z)-octadecatrienoate = (9Z,13S,15Z)-12,13-epoxyoctadeca-9,11,15-trienoate + H2O (9Z,13S,15Z)-12,13-epoxyoctadeca-9,11,15-trienoate = (10Z,15Z)-12-oxophytodienoate kcat is 820 sec(-1) with 9-HPOD as substrate. kcat is 236 sec(-1) with 9-HPOT as substrate. kcat is 99 sec(-1) with 13-HPOD as substrate. kcat is 21 sec(-1) with 13-HPOT as substrate. Expressed in roots. Not detected in aerial tissues, including cotyledons, leaves, stems and flower buds. Expressed early after seed germination, when the radical has just emerged from the seed coat. Not induced in wounded or jasmonate-treated leaves. Belongs to the cytochrome P450 family.