Laboratory cultures
Shoots from a previously isolated clone of a S. caninervisherbarium specimen from southern Nevada, U.S.A. (Stark NV-107,USA, Nevada, Clark County, Newberry Mts, Christmas Tree Pass; UNLV) were cultivated in a growth chamber set to an 18-hour photoperiod (18 °C light, 12 °C dark), at ~30 µmol m-2s-1 PAR in order to compare pigment and antioxidant profiles of field and laboratory-grown plants. Cultures of a single genotype were grown from fragments on 1.2% agar made with an inorganic nutrient solution (Hoagland & Arnon 1950).