The molecular target site of clomazone has recently
been determined. With clomazone, carotenoid synthesis
is inhibited, but no intermediates in the carotenoidcommitted
portion of the pathway accumulate (5,6).
Synthesis of the derivatives of GGPP (gibberellic acid,
phytol, carotenoids) is inhibited by clomazone (5–8).
However, the synthesis of certain sesquiterpenoids and
triterpenoids is not inhibited (9). Until recently, there was
no credible report of the effect of clomazone on any enzyme
of the terpenoid pathway (10–12). This was due to the
fact that clomazone is a proherbicide and that the proper
enzyme had not been tested.
