Monoterpene synthase catalyzing the production of (-)-alpha-pinene, beta-phellandrene and beta-myrcene as the major products. Unable to use farnesyl diphosphate as substrate. Exclusively expressed in the fruit of wild strawberries. Not detected in cultivated varieties. (2E)-geranyl diphosphate = (1S,5S)-alpha-pinene + diphosphate Binds 3 Mg(2+) or Mn(2+) ions per subunit. Secondary metabolite biosynthesis; terpenoid biosynthesis. Expressed in ripe fruits and roots. Not detected in vegetative tissues. Expressed during fruit ripening. 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. Tpsa subfamily.