Study on comprehensive judgement of drought resistance ability of white poplar hybrid clones.
The 20 hybrids studied originated from the double-cross (Populus tomentosa × P. bolleana [P. alba var. pyramidalis]) × (P. alba × P. tremula). Dehydration tolerance, osmotic adjustment, growth and physiological performance were investigated under water stress conditions. Significant differences were observed between the clones for all the parameters. Plant height, single leaf area, photosynthetic and transpiration rates, rate of leaf water loss and osmotic adjustment ability were suggested as criteria for selecting drought resistant clones. The 10 most resistant clones are indicated.