The transfer effect of southern populations of scots pine (Pinus sylvestris L.) on climatic conditions of Lithuania

Abstract

The objective of our study was to assess the quantitative and qualitative traits of southern Scots pine populations and compare these traits with the local populations tested in two field tests in Kazlų Rūda (central Lithuania) and in Venta (north-eastern Lithuania). In total, we measured ca. 3 000 trees in these two tests: (a) direct population transfer (Kazlų Rūda, tree age 45) and (b) test of interpopulation hybrids (Kazlų Rūda, age 25). The results showed that the direct introduction of southern populations of Scots pine into Lithuania would give a negative effect (low survival, inferior stem quality). Apparently, the effect of relatively warmer winters is not strong enough to give an adaptive advantage for the southern over local populations. The cold spells in winter could still be a limiting factor and serious threat to sound development of the southern origins of Scots pine transferred to Lithuania. Transfer of populations from near north (Pskov, Novgorod regions) would give a positive effect on stem straightness, but would slightly reduce wood yield. Therefore, in the absence of a serious threat for adaptedness or no demand for supreme quality timber, we would not recommend the direct introduction of these northerly populations as well. However, the hybridisation field test revealed a superior survival, stem quality and wood yield of hybrids obtained by mating southern mother-trees with the local male parents. Therefore, at present, the introduction of southern genes via admixing southern genotypes in local breeding populations is a better approach than the direct introduction.