Juniperus communis is widespread species on the territory of Russia. High ecological plasticity, polymorphism and adaptation allow growing this species in different ecological conditions and getting at times very important biocenotic value in vegetative communities.

Last decades many researchers mark the reduction of the areas of this species, dying off adult plants, poor seed resumption. Therefore the studying of natural populations of juniper is rather actually. Such researches help to estimate species state in the nature and to reveal processes of morphogenesis and adaptation proceeding in populations.

In the present work the results of studying of variability of morphological signs and correlation structure of 25 natural populations of a Juniper common (J.communis L.), growing on territory of Siberia, Mountain Altai and the Far East are stated. The analysis of the received results has revealed that the signs of vegetative organs vary, as a rule, on middle level, or on high one less often. The signs of generative organs are low variable, irrespective of a growth place. The levels of endogenous and individual variability of signs (especially signs of vegetative organs) depend on features of growth conditions. In severe conditions some decrease of level endogenous variability, but increase in the individual is observed.

The strong correlation of parameters cones and seeds is established. Its relationships are more often middle or strong. The signs of vegetative organs correlate less (the relationships are weak or middle) in comparison with generative one.

The length of needles and the length of annual growth of shoots decrease in the north and in the mountains. The width of needles increases at increasing height above sea level. The sign of generative organs decrease with advancement to the north. The signs of vegetative organs correlate with the sum of positive temperatures, in the frost-free period, mid-annual temperature. Generative organs depend on climatic parameters in lesser degree.

The studying of correlation structure of populations has shown that it dependences on the growth place of individuals. The number of statistically reliable relationships between the investigated signs in different populations is unequally and also depends on parameters of a climate and height above sea level. There, the quantity of reliable relationships increases in unfavorable conditions where plants have constant stress.

Thus, it is established that the correlation of signs, especially in generative sphere increase when growth conditions worsen. On the other hand, some decrease endogenous, but increase in individual variability of investigated signs is observed in such conditions. It promotes successful adaptation of plants to growth conditions and the independence of their organs of environment factors. It confirms works of other researchers (Rostova, 2002; Shemberg, 1987).

The literature:

1. Rostova N.S. Correlation: structure and variability. SPb., 2002. 307 p.

2. Shemberg M. A. Variability of morphological signs and structure of populations of a Betula microphylla // Bil. Glav. botan. Sada, 1987. 146. P. 36-43.

Note. Abstracts are published in author's edition