amitrole. Vegetative parts formed stable complexes with the parent com- 
pound, whereas young reproductive organs cleaved the ring structure of 
amitrole and incorporated the carbon into common biochemical compounds 
such as glucose, sucrose, fructose, and other compounds (Shimabukuro and 
Linck, 1965). Bean plants also transferred large quantities of cl4 from 
serine-U-c!4 to 3-amino-1,2,4-triazolyl-l-alanine (3-ATAL) in both light and 
dark studies. Carbon from alenine-U-c glyoxalate-u-c!*, and formate-c!4 
also entered 3-ATAL but the percentage of conversion was far greater for 
serine. Yeast (Saccharomyces cerevisiae) did not form 3-ATAL from 3-AT in 
72 hours of incubation. 
Toxicity of amitrole has been correlated with chemical analyses and 
it was found that biological response is proportional to the amount re- 
coverable from soils (Frederick, 1961; Sund, 1956). Studies have shown that 
amitrole not only partakes in the soil's base exchange system but that it 
also tends to form complexes with metals (Day et al., 1959, 1961; Castel- 
franco, 1960; Ercegovich and Frear, 1964; Naylor, 1964). 
The major metabolic product formed from amitrole by microbiological 
activity was carbon dioxide. At least thirteen additional unidentified 
compounds were also formed (Ashton, 1963; Riepma, 1962). E. coli converted 
3-ATA into a metabolite, 3-amino-1,2,4-triazolyl alanine. This was incor- 
porated into cellular protein (Williams et al., 1965). Studies with yeast 
showed that imidazolegiycerol phosphate accumulated, presumably because of 
histidine biosynthesis inhibition (Hilton and Kearney, 1965; Klopotowski 
and Hulanicka, 1963; Weyter and Broquist, 1960). 
28 
