Ontogenetic structure of cenopopulations of Allium pskemense (Amaryllidaceae) in Uzbekistan

Many plants of the Allium genus are economically valuable as vegetables. For example, Asian countries are the largest producers of Allium pskemense B. Fedtsch. Ontogenetic spectrum – a sensitive population indicator of changes in the environment – has been noted as useful in recording the age condition of plants. The study focused on the ontogenetic structure of five cenopopulations of A. pskemense, revealing that the examined cenopopulations growing in different ecological-coenotic environmental conditions are normal, and mainly incomplete, i.e. do not include all age groups. Their ontogenetic spectrum was left-sided, and only the coenotic populations 2, 4, 5 coincided with the characteristic spectrum. Depending on ecological-phytocoenotic living conditions, density of individuals in the studied communities ranged 1.75 to 4.50 ind./m2, whereas the ecological density was within 2.00 to 5.29 ind./m2. The research determined that the ontogenetic spectrum shifted to the centered type temporarily due to the uneven processes of the development. Similarities of biological features (long mature generative condition, prevalence of mode of reproduction by seeds, low viability of young individuals) of individuals of this species in various locations, type of cenopopulation, characteristic actual ontogenetic spectra indicate stable conditions for the studied CPs in forbs-Ziziphora-shrub (cenopopulation 5) communities in Uzbekistan.