Interspecific hybridization as a factor reticulate evolution of 5-needle pines from North and East Asia
Diversity structure of 5-needles pines from North and East Asia was studied with classical (anatomical, morphological) and cur-rent (molecular genetic) traits. By set of traits P. pumila and P. koraiensis was intermediate between P. sibirica and P. parviflora, P. sibirica and P. Armandii, respectively. It's allow to suggest that stone pines (subsection Cembrae) are not natural group of species having monophyletic origin but they with some species from white pines (subsection Strobi) form integrated phylogenetic system resulted from reticulate evolution, namely alternation divergence caused by climate and interspecific hybridization. Current genetic interaction between species was studied by way of example P. sibirica and P. pumila in the Transbaikalia. Natural hybrids (up to 5 individuals per ha) are occurred throughout the hybrid zone (Hamar-Daban, Hentey-Chikoyskoe highland Stanove highland). By set of morphological and physiological traits the most of hybrids are intermediate between species. Due to some unbalancing of morpho-logical and physiological adaptation hybrids have reduced resistance in comparison with species, but they are able to active vegeta-tive propagation and occupy relatively free ecological niche in the second tree layer. Fertility of hybrids is significantly less (in the 2-3 times) than that of parental species, but portion of hybrid embryo resulted from pollination by hybrid pollen is higher than portion of hybrid pollen in the total pollen pool of population. Sufficient viability and fertility of natural hybrids between P. sibirica and P. pumila and their aptitude to cross among themselves permit to consider hybrids as a promising evolutional new formation that can result in novel species.