Involved in the formation of (E)-beta-farnesene and (3E)-4,8-dimethyl-1,3,7-nonatriene, key signal molecules in induced plant defense mediated by the attraction of enemies of herbivores (PubMed:12481088). In the presence of geranyl diphosphate, catalyzes the formation of the acyclic monoterpens (3R)-linalool and geraniol (PubMed:12481088). However, the in vitro rate of sesquiterpene formation is about four times higher than the rate of monoterpene formation (PubMed:12481088). Mediates the conversion of ent-copalyl diphosphate into ent-kaurene, thus having probably a role in gibberellin biosynthesis (PubMed:26620527). (2E,6E)-farnesyl diphosphate = (E)-beta-farnesene + diphosphate (2E,6E)-farnesyl diphosphate + H2O = (3R,6E)-nerolidol + diphosphate (2E,6E)-farnesyl diphosphate + H2O = (2E,6E)-farnesol + diphosphate (2E)-geranyl diphosphate + H2O = (2E)-geraniol + diphosphate (2E)-geranyl diphosphate + H2O = (R)-linalool + diphosphate ent-copalyl diphosphate = diphosphate + ent-kaur-16-ene Binds 3 Mg(2+) or Mn(2+) ions per subunit. Optimum pH is 7.0. Optimum temperature is between 30 and 37 degrees Celsius. Secondary metabolite biosynthesis; terpenoid biosynthesis. Plant hormone biosynthesis; gibberellin biosynthesis. Monomer. Expressed in leaves and sheath tissues. Not detected in roots. By herbivory, wounding or elicitor treatments in young leaves of cv. B73, but not of cv. Delprim (PubMed:12481088). Induced transiently by F.graminearum and combination of jasmonic acid (JA) and ethephon (EP), an ethylene precursor (PubMed:26620527). The Asp-Asp-Xaa-Xaa-Asp/Glu (DDXXD/E) motif is important for the catalytic activity, presumably through binding to Mg(2+). Belongs to the terpene synthase family.