Seed germination of woody and shrubby introduced species

Abstract

The article presents the research results of seed germination of woody and shrubby introduced species. Depending on the depth of dormancy, the studied plant species were divided into 3 groups. The first group includes plants with the absence of dormancy or with a short dormancy; the seeds of these species do not need stratification. The second group includes plants whose seeds are in a state of a rather long intermediate physiological dormancy; they need cold stratification. The organic dormancy period of plant seeds of the second group is different – from 25 to 160 days. As a rule, these are plants with a well-formed seed bud. The physiological dormancy of the seed bud and the inhibitory effect of its covers can be an obstacle to its formation. The third group includes plants whose seeds may not germinate for several years. As a rule, the seeds of these plants are in a state of a deep physiological or morphophysiological dormancy; multi-stage stratification is recommended for their germination. The introduced species of the third group are the most difficult to study since their seeds can belong to different variants of deep dormancy, which combines the physiological immaturity of different structures of the seed bud with the incomplete morphological maturity and exogenous dormancy.