The metabolism of atrazine was investigated in resistant com 
(Zea mays L.) and sorghum (Sorghum vulgare Pers.), in intermediately 
susceptible pea (Pisum sativum L.), and in highly susceptible wheat 
(Triticum vulgare Vill.) and soybean (Glycine max Meril.). Results of 
these studies showed that two pathways for atrazine metabolism existed. 
All higher plants studied were able to metabolize atrazine by N-dealkyla- 
tion of either of the two alkylamine groups. In addition to this, those 
plants containing benzoxazinone (Corm and wheat) were also able to de- 
toxify atrazine by hydrolysis in the 2-position and formation of hydroxy- 
atrazine (1292, 1293, 1294, 1295, 1297). In corm, atrazine metabolism 
yielded the desethyl 2-hydroxy and desisopropyl 2-hydroxy atrazine analogs 
as well as the 2-hydroxyatrazine (1748). In the leaves of corn and sorghun, 
two sulfur compounds have also been found and identified as: S-(4-ethyl- 
amino-6-isopropylamino-2-s-triazino) glutathione and y-glutamyl-S-(4-ethyl- 
amino-6-isopropylamino-2-s-triazino)cysteine. Both compounds form rapidly 
in leaf discs incubated with atrazine. An enzyme system has been isolated 
from corm and sorghum leaves which catalyzes the formation of metabolite 
from atrazine and glutathione (1759). The hydroxyatrazine was also observed 
in cotton (Gossypium hirsutum L.) (122 ). 
Hydroxyatrazine was detected as a degradation product after perfusion of 
soils with atrazine (32, 614, 615, 616). Hydrolysis was apparently largely 
responsible for the degradation. The rate of hydrolysis to form hydroxy- 
atrazine in aqueous systems, or in systems containing sterilized soil, was 
first-order (31). Side chain and ring cleavage occurred in solution 
culture studies (1771). On montmorillonite, chemical degradation occurred. 
NMR and infrared studies showed that the hydrolytic degradation product was 
predominantly the keto form of the protonated hydroxy analog (1590). 
clio, production from ring-labeled atrazine by microorganisms has been 
observed (7, 349). The fungus, F. roseum, metabolized atrazine to hydroxy- 
atrazine (309). Penicillium cyclopium, P. frequentans, P. purpurogenum, 
Aspergillus niger, A. repens, Ceyhalosporium acre monium and Cladosporium 
herbarum also decomposed atrazine (984). 
With Fenton's reagent, atrazine underwent side chain hydroxylation 
(1676). 
$Ht 
+H + | 
“> 
& hd ‘? | ——> nly ¢: Co ~CH, welt — 
~CH, 
H 
S19 
