Plant lipoxygenases may be involved in a number of diverse aspects of plant physiology including growth and development, pest resistance, and senescence or responses to wounding. May contribute to cell death during the hypersensitive response (HR) by the massive production of free fatty acid hydroperoxides. Catalyzes the hydroperoxidation of lipids containing a cis,cis-1,4-pentadiene structure. (9Z,12Z)-octadecadienoate + O2 = (9S)-hydroperoxy-(10E,12Z)-octadecadienoate Binds 1 Fe cation per subunit. Iron is tightly bound. Lipid metabolism; oxylipin biosynthesis. Monomer. Not detected in leaves, stems, flowers, roots, tubers and stolons during normal growth and development. Up-regulated within 6 hours after pathogen infection, ethylene or jasmonate treatments. Not induced by wounding. Belongs to the lipoxygenase family.