Morphological and genetics analysis of Stachys sylvatica (Lamiaceae) coenopopulations in the mountains of South Siberia

Abstract

Stachys sylvatica is Tertiary nemoral relict from the Sout Siberian mountains. Modification and genetic variability of 11 Stachys sylvatica populations from South Siberian mountains were studied. Investigations revealed that S. sylvatica grew in coniferous (spruce, pine, Siberian stone pine, fir, and mixed forests), aspen, linden forests and floodplain habitats. Climatic area of the species is limited to an annual precipitation of 500–1250 mm, effective heat sum 1600–2050 ºC and altitude from 150 to 700 m a.s.l. In the study of the state of the S. sylvatica coenopopulations we determined the population size, projective cover, evaluated the morphological variability of vegetative and genera­tive characteristics. To establish the significance of differences between the average values of the same characters we used ANOVA. It was revealed that most of the morphometric characters had medium and high level of variability. The genetic variability of species we detected by RAF-PCR method (Randomly Amplified DNA Fingerprinting). The analysis of genetic variation of the S. sylvatica coenopopulations showed that the studied species was characterized by a very high level of intra-population polymorphism. The maximum level of genetic variability was observed in the population growing on the border of the species area. Gene pools of all studied coenopopulations have a satisfactory condition and can be reproduced by itself. All studied coenopopulations of Stachys sylvatica are poorly differenti­ated and do not show the tendency to the formation of new taxa. Moreover, a similar genetic structure we have seen in the coenopopulations growing not only in different parts of the area, but also in communities radically different in environmental and phytocenotic conditions. With increasing of anthropogenic impact on coenopopulations we have observed an increase of the size of the generative organs of Stachys sylvatica. The separation of individuals on a geographical basis was revealed based on the analysis of morphological characters of S. sylvatica. Investigations revealed that Stachys sylvatica had wide ecological amplitude and significant variability in the stressed environmental conditions (compared to other nemoral (Tertiary) relicts). It is characterized by a high level of intrapopulation genetic variability and low degree of population differentiation.