TRANSPORT AND ACCUMULATION OF PACLOBUTRAZOL IN PEACH SEEDLINGS

Peach seedlings were grown for 9 days in nutrient solutions containing 100 ppb of ¹⁴C-paclobutrazol.
Paclobutrazol (PBZ) was readily taken up and transported throughout the plants.
Total ¹⁴C activity was distributed predominantly between roots and leaves.
However, the concentration of ¹⁴C activity (¹⁴C dpm mg^-1 fresh wt) was highest in leaves and relatively uniform throughout the remainder of the plant.
This pattern is consistent with the idea that PBZ is transported via the xylem.
Additionally, microautoradiographs of the transport tissues showed that ¹⁴C activity was associated exclusively with the xylem.

Though relatively stable in the nutrient solution, ¹⁴C-PBZ breakdown was rapid in the plants.
Breakdown of ¹⁴C-PBZ was highest in the most physiologically active areas of the plant, the leaves and the young stem.

VI International Symposium on Growth Regulators in Fruit Production

J.D. Early, G.C. Martin

https://doi.org/10.17660/ActaHortic.1989.239.6