R. Gimenezespinosa et R. Deprado, ABSORPTION, TRANSLOCATION AND METABOLISM OF PYRIDATE IN CHICKPEA (CICER-ARIETINUM), Australian journal of plant physiology, 25(1), 1998, pp. 105-110
This work studied the tolerance mechanisms of chickpea (Cicer arietinu
m L.) to pyridate, a post-emergence herbicide used in other crops such
as maize, peanut and wheat. Foliar absorption of pyridate in chickpea
was limited and occurred mainly during the first 24 h after treatment
. Over 83% of the herbicide absorbed remained in the treated leaf 72 h
after treatment. Twelve hours after herbicide treatment, 50% of the t
otal herbicide applied was converted to CL9673-N-Gly, an intermediate
metabolite essential in the activation of the pyridazine ring for foll
owing conjugations. The N-glycoside was conjugated to form more-polar
metabolites, C1 and C2: C1 was identified as CL9673-N-Gly-glutathione;
and C2 was identified as CL9673-N-Gly-cysteine. C1 appeared 3 h after
treatment and reached a maximum of around 40% of recovered radioactiv
ity 72 h later, while C2 appeared 24 h after treatment and reached a m
aximum of 10% 72 h later. Chickpea glutathione transferases do not see
m to be involved in the formation of C1, thus the final amount of this
conjugate mainly depends on the amount of N-glycoside formation in vi
vo.