Metabolism and translocation of 3-amino-1,2,4-triazole in Pinus pinea

Metabolism of 3-amino-1,2,4-triazole was studied in 28-day-old seedlings of Pinus pinea injected with 5-14C-labelled 3-amino-1,2,4-triazole into the hypocotyl or tip of one of the 13 cotyledons. The seedlings were allowed to metabolize the labelled triazole for a period of 4, 14, or 21 days and were harvested and separated into cotyledons, apex, hypocotyl, and roots. The label upon extraction from the various parts was partially purified through a Dowex 50 W-8 resin exchange column and eluted with NH4OH and water for thin-layer chromatography. The radioautographs showed several metabolites including unmetabolized amitrole in all parts after 4 days of metabolism. Two of the slower running metabolites correspond to 'unknown I' orX1 and X3 previously reported in Pinus ponderosa and Abies concolor and the two faster running metabolites have not been reported before. The metabolism of amitrole seems to occur in both hypocotyl and cotyledons (sites of injection) and the metabolites, as well as unmetabolized, fr...