Picloram (Tordon) [4-Amino~-3,5,6-trichloropicolinic acid] 
Carboxy-labeled picloram was applied to cotton plants and the 
metabolism studied. Only labeled C0, was identified as a metabolite. 
Hydrolysis with 6 N-HCl of unextractable radioactivity indicated that 
about 3% of the tordon was probably combined with terminal amino groups 
of protein in the cotton plant (971, 972). 
Wheat seedlings were grown in soil treated with picloram. Analysis 
of plant material indicated the presence of oxalic acid, 4-amino-3,5- 
dichloro-6-hydroxypicolinic acid, unchanged picloram and lipids hydroly- 
zable to all three acids and 4-amino-2,3,5-trichloropyridine (1199, 1201). 
Attempts to isolate organisms that could utilize picloram as a 
good energy source were unsuccessful. However, a number of organisms 
were found capable of degrading this herbicide if a supplementary energy 
source were made available (1533). 
Bacillus cereus 
Bacillus subtilis 
Nocardi opaca (ATCC-4276) 
Agrobacterium radiobacter (ATCC-4718) 
Arthrobacter globiformis (ATCC-8010) 
Flavobacterium aquatile (ATCC-11947) 
Aspergillus niger (ATCC-6275) 
Aspergillus terreus 
Botrytis alii 
Penicillium digitatum 
Trichoderma lignorum 
Saccharomyces cerevisiae 
Helminthosporium pedicellatum 
Degradation studies of picloram in soil were conducted. 
t = 0.693/,, 
1/2 
In Regina heavy clay, at 25°C and at moisture holding capacity, "1p - 
68 +10 days (569). 
Picloram was degraded rapidly by short wave ultraviolet light but 
slowly by sunlight (986). 
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