PRE-SOWING SEED TREATMENT WITH PHYSICAL STRESSORS INDUCES CHANGES IN AMOUNT OF SECONDARY METABOLITES IN NEEDLES OF PICEA ABIES SEEDLINGS

Tree resistance to pathogens is related to the general viability of trees, their growth energy, and ability to synthesize and to mobilize secondary metabolites (SMs), usually phenolic compounds, in tissues. The total phenolic content (TPC) in Norway spruce needles was determined during two vegetation seasons in order to compare the chemical background and ability of different Norway spruce half-sib families to synthesize TPC in response to seed treatment with physical stressors: cold plasma for 1 and 2 min (CP1, CP2) and electromagnetic field for 2 min (EMF2). TPC in seedling needles significantly differed between affected and control groups, but differences were stronger exerted during the first year of vegetation. In the first vegetation season, the strongest positive effects on TPC synthesis were induced by EMF2 treatment in 463 and 577 half-sib families, by CP1 treatment − in 457 half-sib family and by CP2 treatment − in 541 half-sib family; in the second vegetation season strongest effects were detected in CP1 treated 457 half-sib family and in CP2 treated 548 and 477 half-sib families. The half-sib families of Picea abies with higher TPC induced by seed treatment with different physical stressors could be more resistant to pathogens and diseases. The variance component of family for TPC variated from 14±10 % till 17±11 %, and was significant. The interaction of genotype and environment on TPC was as high as 49 ± 20%

Genetics of Dispersal

Dispersal is a process of central importance for the ecological and evolutionary dynamics of populations and communities, because of its diverse consequences for gene flow and demography. It is subject to evolutionary change, which begs the question, what is the genetic basis of this potentially complex trait? To address this question, we (i) review the empirical literature on the genetic basis of dispersal, (ii) explore how theoretical investigations of the evolution of dispersal have represented the genetics of dispersal, and (iii) discuss how the genetic basis of dispersal influences theoretical predictions of the evolution of dispersal and potential consequences. Dispersal has a detectable genetic basis in many organisms, from bacteria to plants and animals. Generally, there is evidence for significant genetic variation for dispersal or dispersal-related phenotypes or evidence for the micro-evolution of dispersal in natural populations. Dispersal is typically the outcome of several interacting traits, and this complexity is reflected in its genetic architecture: while some genes of moderate to large effect can influence certain aspects of dispersal, dispersal traits are typically polygenic. Correlations among dispersal traits as well as between dispersal traits and other traits under selection are common, and the genetic basis of dispersal can be highly environment-dependent. By contrast, models have historically considered a highly simplified genetic architecture of dispersal. It is only recently that models have started to consider multiple loci influencing dispersal, as well as non-additive effects such as dominance and epistasis, showing that the genetic basis of dispersal can influence evolutionary rates and outcomes, especially under non-equilibrium conditions. For example, the number of loci controlling dispersal can influence projected rates of dispersal evolution during range shifts and corresponding demographic impacts. Incorporating more realism in the genetic architecture of dispersal is thus necessary to enable models to move beyond the purely theoretical towards making more useful predictions of evolutionary and ecological dynamics under current and future environmental conditions. To inform these advances, empirical studies need to answer outstanding questions concerning whether specific genes underlie dispersal variation, the genetic architecture of context-dependent dispersal phenotypes and behaviours, and correlations among dispersal and other traits.Peer reviewe

Life history traits and broadleaved tree genetics

Most broadleaved tree species play a minor role in Scandinavian and Baltic forestry, therefore little information on metric trait variation exists so far. The Forestry Convention signed by many European countries requires that gene conservation programs have to be developed for broadleaved tree species. Studies of within- and among-population genetic variation are of great importance for gene conservation strategy and the design of gene conservation and long-term breeding programmes. Our hypothesis is that life history traits influence the among- and within-population genetic variation. Three experiments, with different sets of species included in each, were conducted in Sweden. We have selected populations of Quercus robur, Fagus sylvatica, Fraxinus excelsior, Acer platanoides, Primus avium, Prunus padus, Sorbus aucuparia and Alnus glutinosa from across their range of distribution in Sweden. A complementary study of progenies of Lithuanian Quercus robur populations was done in a Lithuanian experiment. Open pollinated families were studied in all experiments, covering ages 2-6. Except for bud flushing, there was no clear evidence for increased within-population variation for climax compared to pioneer species in the traits studied. Substantial gene flow may occur even in intermediate and insect pollinated species. The largest within-population variation estimates, regardless of species, occurred for bud flushing. A strong parent-offspring relationship was revealed for bud flushing in Quercus robur, which indicates the presence of assortative mating in the populations. In addition, strong and stable genetic correlations across years in all species suggest high juvenile-mature correlations for this trait. The genetic parameters of populations from our experiments showed that northern and southern populations are equally good for gene conservation purposes

Pedunculate and Sessile Mixed Oak Forest Regeneration Process in Lithuania

Pedunculate and sessile oak species are sympatric. These oaks hybridize with one another, and this process influences the development of undergrowth. The purpose of this study was to determine how different oak species influence the forest regeneration process. For this purpose, the forest was divided into eight transects of 300 m and 100 m widths, distinguished into temporary plots of 10 m in diameter covering the whole territory of the forest. The distribution of oak undergrowth was calculated by four oak height groups, determining the composition of the first storey, covering of underbrush and herbaceous plant, and forest site. We determined that the spread of oak differed depending on the first storey tree species and underbrush. Grass cover was the biggest influence on the sessile oak. The impurity of sessile oak in oak stands had a positive impact on the development of undergrowth, since the entire undergrowth develops faster than separate components of the undergrowth

Spread intensity and invasiveness of sycamore maple (Acer pseudoplatanus L.) in Lithuanian forests

The primary objectives of this study were to estimate seedling abundance, spread intensity, and invasiveness of sycamore maple (Acer pseudoplatanus L.) in Lithuanian forests. The species was introduced to Lithuania in 1802, and since then has subsequently become gradually invasive. Seedling understory abundance, colonization and dispersal were investigated in six forest blocks covering the principal sycamore distribution areas in southwestern Lithuania. Seedlings height and densities in the undestory were evaluated, and seedlings assigned to four height groups. Species invasiveness was estimated applying the Pest Plant Prioritization Process (PPPP), based on the Analytic Hierarchy Process (AHP) method. Results showed the average spread distance from the parent tree was 257 m, with a mean seedling number per hectare of 2064. Sycamore maple invasive score was 0.6426 (range: 0-1), the current relative to potential distribution rating was 0.57, and the social, environmental, and economic impact score was 0.1682. Such values were used to assess the Pest Plant Score for sycamore maple, obtaining a value (0.3537) lower than expectations (0.5). Results indicated that the species exhibits invasive properties and a rapid spread in the study area. Some implications of the above results in view of the upcoming climate change and the use of sycamore maple in Lithuanian forest plantations are discussed

Leaf morphological variation of sessile oak (Quercus petraea, (Matt.) Liebl.) and pedunculate oak (Quercus robur, L.) in Lithuania

Leaf morphology was assessed in Pajiesys and Seirijai field trials of oaks. Oaks in these trials are the progenies of oak trees (Quercus genus) that grow in the Trakas forest of Seirijai district of Alytus forest enterprise of Lithuania. The aim of the study was to determine the number of hybrid trees between the progenies of the Trakas forest in Pajiesys and Seirijai field trials. 251 oaks belonging to 40 half-sib families were sampled. Twenty three leaf morphological variables were measured on each of 5 leaves collected from each tree and analysed by principal component analysis (PCA) and discriminant analysis (DA). The study concluded that Q. robur and Q. petraea leaves are most clearly identified by six morphological traits. Discriminant function of two traits for oak species separation was proposed. The study has also revealed a high degree of interspecific hybridization in field trials. Study results were compared with earlier reports about hybridization occurring in mixed oak stands in other parts of EuropeLietuvos agrarinių ir miškų mokslų centro filialas Miškų institutasVytauto Didžiojo universitetasŽemės ūkio akademij

EUFORGEN 12-sis vykdomojo komiteto susirinkimas

Vytauto Didžiojo universitetasŽemės ūkio akademij

Reikia tęstinės Miško genofondo išsaugojimo ir selekcijos plėtros programos

Vytauto Didžiojo universitetasŽemės ūkio akademij

Genetic and environmental factors impact on scots pine (Pinus sylvestris L.) wood hardness

Tyrimai atlikti Lietuvos pušies populiacijų palikuonių 1983 metų serijos keturiuose bandomuosiuose želdiniuose. Kiekvienuose želdiniuose auga 140 pusiausibų šeimų iš septynių Lietuvos populiacijų. Matuotos 30 metų amžiaus pušys. Buvo matuojamas ar vertinamas stiebo skersmuo, medienos kietumas, šeimų išlikimas. Medienos kietumas matuotas prietaisu Pilodyn 6J. Vidutinis Pilodyn prietaiso adatos smigimo į pušies medieną gylis buvo 19,3 mm. Vidutinis skirtumas tarp pušies šeimų vidurkių buvo 4,5 mm, o tarp bandomųjų želdinių – 3,1 mm. Nustatytas individualus medienos kietumo paveldėjimo koeficientas buvo 0,30, o šeimos – 0,65. Šeimos ir pakartojimo želdiniuose sąveika buvo reikšminga (variacijos komponentas siekė 11,0± 0,9 %) ir stipresnė nei šeimos ir želdinių sąveika, kuri siekė 7,1± 0,7 %. Nustatyta, kad tik šeimos efektas medienos kietumui buvo statistiškai patikimas. Nepaisant nemažų želdinių ir pakartojimų (blokų) variacijos komponentų dėl didelių paklaidų šie efektai nebuvo statistiškai patikimi. Populiacijos įtaka buvo nereikšminga. Kiečiausia mediena buvo mažiausio skalsumo medyne derlingesnėje augavietėje140 Scots pine halfsib families from 7 Lithuanian populations were tested at age 30 in series of four field trials established in 1983. Stem diameter, wood hardness, family survival were studied. Wood hardness was tested by using Pilodyn 6J. Mean value of Pilodyn pin penetration for pine families was 19.3 mm. The average difference between family mean estimates was 4.5 mm, between the sites – 3.1 mm. Individual heritability for wood hardness was 0.30, family heritability – 0.65. Family and block interaction in this trait was significant (variance component was 11.0± 0.9 %) and stroger than family x site interaction (7.1± 0.7 %). Only family effect for wood hardness was significant. Site and block effects even being large but due to its standard errors were not significant. Population effect was not significant as well. The hardest wood was estimated in less dense stand growing in richer soilVytauto Didžiojo universitetasŽemės ūkio akademij