Abstract:

  Isoperoxidases of 26 species and 2 varieties, belonging to 5 sections of Populus,

were analysed by means of polyacrylamide gel slab electrophoresis. Experimental

evidences indicate that the zymograms of petioles are stable.  Whole anodal isozymes

may be divided into 5 groups; a.b.c.d.e.  Every species of Populus shared the c group

isozymes. The b group is limited within the section Leuce, and only in this section, the

a group enzymes are absent.  The d group is very complicated, and fully expressed the

species-specificity.  Base on their specific zymograms, it is easy to distinguish one

species from the others, sometimes, we can characterize the varieties, even some clones.

It seems that, in the course of morphological evolution of Populus, the divergence of

their isoperoxidases also occurred.