Phosphorus, copper and zinc supply levels influence growth and nutrition of a young Populus trichocarpa (Torr. & Gray) × P. deltoides (Bartr. ex Marsh) hybrid
Author: van den Driessche, R.
Source: New Forests, Volume 19, Number 2, March 2000 , pp. 143-157(15)
Abstract:Growth and nutrient responses of a P. trichocarpa × P. deltoides hybrid to phosphorus (P), copper (Cu) and zinc (Zn) were examined in a 4P × 3Cu × 3Zn factorial experiment conducted in an unheated greenhouse from 20 May until 25 August, 1997. Increase of growth medium P concentration from 37 to 356 mg kg^-1 resulted in a mean increase in tree dry weight of 53%, and increase of P concentration from 37 to 500 mg kg^-1 was associated with a stem volume increase of 47%. Increase from 0 to 0.32 µM Cu in solution applied thrice weekly was associated with a 61% increase in tree dry weight and a 59% increase in stem volume. There was also a smaller increase in stem volume (9.4%) resulting from increase in concentration of Zn from 0 to 0.31 µM in nutrient solution. Mean minimal leaf concentrations for satisfactory stem growth were found to be 2.5 g kg^-1 P, 2.4 mg kg^-1 Cu and 74 mg kg^-1Zn. Visual deficiency symptoms were associated with mean leaf P concentrations below 1.6 g kg^-1, and Cu concentrations below 1.7 mg kg^-1. Increase in leaf P concentration was associated with decreases in leaf Cu and Zn concentrations, and high leaf Zn appeared to compensate in some degree for low leaf Cu. Total plant dry weight was satisfactorily predicted by stem volume (r^2 = 0.85), but not by mean leaf weight or area.
Document Type: Regular Paper
Affiliations: Department of Biology, University of Victoria, P.O. Box 3020, Victoria, B.C. V8W 3N5, Canada
Publication date: 2000-03-01