%0 Research article
%T Can physiological and anatomical characters be used for selecting high yielding hybrid aspen clones?
%A Yu, Qibin
%D 2001
%J Silva Fennica
%V 35
%N 2
%R doi:10.14214/sf.591
%U https://silvafennica.fi/article/591
%X Stomatal, CO2 exchange parameters and several leaf and growth traits  were recorded in a five-year-old hybrid aspen clone trial. The field  trial consisted of four aspen hybrid clones (Populus tremula L. x  P.  tremuloides Michx.) and one local Populus tremula seedling source. The  mean estimated height of hybrid aspen clones was 1.6 times higher than  for P. tremula. Similarly, basal diameter was 1.5 times and breast  diameter 1.8 times higher in the hybrids. Differences were observed for  physiological and growth traits among hybrid clones and P. tremula, but,  only stomatal characters of hybrid clones differed significantly from  those in P. tremula. Hybrid clones had larger guard cells (22.9 mm) than  P. tremula (19.2 mm), whereas P. tremula had a higher stomatal density  (211.3/mm2) than the hybrid clones (164.4/mm2). Among four hybrid  clones, net photosynthesis was strongly correlated with foliar nitrogen.  Height correlated significantly with foliar nitrogen, but negatively  with leaf fresh weight, leaf dry weight and stomatal density. The  results suggested that yield components could be controlled by many  genes, specific to each clone. No single gas exchange or morphological  variable can provide a reliable indicator of yield potential.