The enzyme from Zea mays, variety B73, gives mainly 7-epi-sesquithujene with (S)-beta-bisabolene and traces of other sesquiterpenoids, cf. EC 4.2.3.55 (S)-beta-bisabolene synthase. It requires Mg2+ or Mn2+. The product ratio is dependent on which metal ion is present. 7-epi-Sesquithujene is an attractant for the emerald ash borer beetle.
The variability of sesquiterpenes emitted from two Zea mays cultivars is controlled by allelic variation of two terpene synthase genes encoding stereoselective multiple product enzymes.