Uptake of Triticonazole,during Imbibition,by Wheat Caryopses after Seed Treatment

The uptake of ¹⁴C-labelled triticonazole by wheat caryopses during imbibition was investigated. The uptake from an aqueous solution appeared to be driven by mass flow rather than by accumulation in seed lipids. During treatment with a liquid seed-dressing preparation of triticonazole, c. 1 μg triticonazole per caryopsis (2·4% of applied triticonazole) entered the seed. During germination in soil, another c. 1 μg triticonazole per caryopsis entered the seed in 24 h. In killed seeds, no penetration was observed between 24 h and 72 h after the beginning of imbibition. After seed treatment and imbibition in soil, triticonazole appeared to be located in the seed coats and embryo, but not in endosperm; experiments suggested that the testa acted as a barrier. Under our conditions, the pathway from seed coats to shoots was not an important route for triticonazole uptake by the shoots. © 1997 SCI.