M. Sidari et al., EFFECT OF IMAZAMETHABENZ-METHYL ON NITRATE UPTAKE IN WHEAT (TRITICUM-DURUM L.), Journal of agricultural and food chemistry, 46(7), 1998, pp. 2800-2803
The effect of the herbicide imazamethabenz-methyl (IMZM), a mixture of
the two isomers methyl hylethyl)-5-oxo-1H-imidazol-2-yl]-4-methylbenz
oate (para isomer) and methyl hylethyl)-5-oxa-1H-imidazol-2-yl]-5-meth
ylbenzoate (meta isomer), on the uptake of nitrate by wheat grown hydr
oponically was studied. IMZM stimulates the nitrate uptake in both ''i
nduced'' (NO3--pretreated) and ''uninduced'' (NO3--starved) seedlings,
most likely as a response to a plant stress. The decrease in acetohyd
roxy acid synthase (AHAS; EC 4.1.3.18) activity and in protein content
of IMZM-treated roots supports this hypothesis. The presence of valin
e, leucine, isoleucine, and IMZM prevents the effects of the herbicide
treatment in both induced and uninduced plants. The addition of IMZM
to humic acid enhances the nitrate uptake, although to a lower extent
than with the herbicide alone. Possible traces of imazamethabenz acid
(IMZA) in growing units do not seem to be responsible for the greater
N demand observed.