Intact olive callus cultures were used to investigate any possible eff
ects which dimethoate, a commonly used organophosphorus insecticide in
olive agriculture, may have on lipid synthesis. Dimethoate was applie
d to the surface of callus cultures and the incorporation of radioacti
vity from [C-14]acetate into acyl lipids monitored. The effect of the
insecticide depended very much on its concentration. High levels (up t
o 500 mu M) resulted in overall inhibition of lipid synthesis and in c
hanged patterns of both lipid class and fatty acid labelling. At 10 mu
M on the other hand, dimethoate had relatively little effect on norma
l labelling patterns except for a reduction in incorporation into unsa
turated fatty acids. The possible relevance of these findings to the a
gricultural use of dimethoate are discussed. (C) 1998 Elsevier Science
Ltd. All rights reserved.