Hypothesis of genetic integration of Pinus sylvestris L. populations in the valley of Ob river

Abstract

Verification results of one corollary of developing theory of the authors about the coniferous hydrochory (Sannikov, Sannikova, 2007) – a hypothesis of genetic integration of Scots pine Pinus sylvestris L. populations in the direction of rivers flow – have been cited. The average genetic Nei`s distance (Nei, 1978; 0.0024 ± 0.0015) between the 8 adjacent P. sylvestris populations on the transect along all the Ob valley (Lake Teletskoje–Barnaul–Tomsk–Surgut–Khanty-Mansiisk–Geologicheskii–Berezovo–Synja), that is twice time less as between the 14 populations on the Ob`s watersheds with the adjacent rivers (Yenisei, Irtysh, Pur, Konda, Tavda, Nadym) (0.0049 ± 0.0009), has been determined on the basis of comparative allozyme analysis (Nei, 1978; 0.0024 ± 0.0015). Corresponding average gradient of the genetic distances between the population located along the Ob river-bed is also 70 % less (0.66 ± 0.43), than on the transects directed across the watersheds (1.40 ± 0.43). Probably, a lesser genetic distance and its gradients, which revealed between the Scots pine populations along river-bed Ob in comparison with ones on the transects directed across the watersheds, depended on greater rate of its seed hydrochory (up to 800 km/1000 yr) in comparison with the anemochory on the watersheds. As a whole, a hypothesis about more speed (prioritic) hydrochoric dispersal and relative genetic integration of Scots pine populations along the rivers flow in comparison with anemochoric dispersal on the watersheds has been corroborated on the basis of results generalization of the present and preceded research.

Keywords

• Pinus sylvestris
• population
• hydrochory
• genetic distance
• differentiation
• integration
• watershed
• river Ob
• valley