Amo 1618 and sterol biosynthesis in tissues and sub-cellular fractions of tobacco seedlings

Amo 1618 inhibited the incorporation of MVA-2-¹⁴C] into sterols (in particular the 4-desmethylsterols) and promoted its accumulation in squalene-2,-3epoxide in intact seedlings, tissues from treated seedlings, and sub-cellular, membraneous fractions of treated 21-day-old tobacco seedlings. The stem tissues appeared to have a greater sterol requirement (on a per gram fresh weight basis) than leaf tissues and incorporation of radioactivity into stem sterols was more susceptible to inhibition by Amo 1618 than incorporation into leaf tissue.