Uptake and Translocation of Terbacil in Strawberry (Fragaria×ananassa) and Goldenrod (Solidago fistulosa)

Abstract

Terbacil (3 -tert- butyl - 5 - chloro - 6 - methyluracil) uptake by roots and translocation were evaluated as possible bases of tolerance in two species, strawberry (Fragaria×ananassaDuchesne 'Sunrise’ and ‘Guardian’) and goldenrod (Solidago fistulosaMiller). Tolerance of goldenrod to terbacil was at least five-fold that of strawberry. Strawberry was at least four - fold more tolerant than highly terbacil - sensitive cucumber (Cucumis sativusL. ‘Chipper’). Guardian, a reported susceptible strawberry cultivar, was as tolerant to terbacil as the tolerant cultivar, Sunrise. Distribution of14C within the plant, but not uptake of label through roots, was found to be correlated to relative tolerance to terbacil when the roots of intact plants of all species were exposed for various time periods to a nutrient solution containing 2 -14C terbacil. The observed distribution patterns suggest that tolerance to terbacil in strawberry and goldenrod is at least partially attributable to the restricted translocation of root - absorbed herbicide. The greater tolerance of goldenrod than strawberry to terbacil was apparently unrelated to the restriction of herbicide to root tissue.