Genetic differentiation of Allium sibiricum L. populations in Poland based on their morphological and molecular markers

<em>Allium sibiricum</em> is one of the rarest plant species in the Sudetes and Carpathians. Inter simple sequence repeat DNA (ISSR) and morphological analyses were conducted to study the biogeographical relationships between geographically disjunctive populations of <em>A. sibiricum</em> in the Carpathians and Sudetes. The results clearly differentiated the Carpathian and Sudetes populations, but also showed a relatively high level of genetic similarity in specimens within certain groups of the Sudetes and Carpathian populations. The plants collected in the Karkonosze probably belong to a mountain form of <em>A. schoenoprasum</em> morphotype C which inhabits natural sites there. In contrast, the study found morphologically and genetically different plants inhabiting Pilsko Mt in the Carpathians. The plants from the Carpathians were present in scattered sites probably due to the activity of Vlach shepherds and the formation of large pastures. The species enlarged its local range due to this type of anthropopressure and likely hybridized with the cultivated <em>Allium</em> plants introduced by the shepherds. This may indicate that the populations on Pilsko Mt are of a partly anthropogenic character.

Molecular variance and population structure of lentil (Lens culinarisMedik.) landraces from Mediterranean countries as revealed by simple sequence repeat DNA markers: implications for conservation and use

The Mediterranean region has a rich history of domestication and cultivation of lentil (Lens culinarisMedik.). Landraces have been grown and repeatedly selected by local farmers under different agro-environments. Characterization of molecular variation and genetic differentiation helps to ensure enhanced valorization, conservation and use of these genetic resources. Nineteen Simple Sequence Repeat DNA markers were used for molecular variance analysis (AMOVA) and population structure assessment underlying 74 lentil landraces from four Mediterranean countries: Morocco, Italy, Greece and Turkey. Based on AMOVA, presence of population structure and genetic differentiation at different levels were evidenced. Genetic diversity among Turkish landraces was higher than that of other countries. These landraces were more homogeneous as shown by low genetic differentiation among individuals within each landrace. Whereas Moroccan landraces followed by Italian and Greek provenances showed higher diversity and differentiation among individuals within landraces. The wide genetic variability of these landraces could help to better adaptation to biotic and abiotic stresses. Moreover, they could provide useful alleles related to adaptive traits for breeding purposes. Based on structure analysis, we obtained indications of possible presence of two major gene pools: a northern gene pool composed of Turkish, Italian and Greek landraces, and a southern gene pool composed of Moroccan landraces. Our results could be of interest when designing future diversity studies, collection missions, conservation and core collection construction strategies on Mediterranean lentil landraces.

Distribution of white spruce lateral fine roots as affected by the presence of trembling aspen: root mapping using simple sequence repeat DNA profiling

Mixedwood forests of white spruce ( Picea glauca (Moench) Voss) and trembling aspen ( Populus tremuloides Michx.) may possess ecological advantages over monospecific white spruce stands. Belowground competition may be reduced through vertically stratified roots; facilitation of growth may occur in upper soil layers through nutrient-rich trembling aspen litterfall. These effects may incentivize white spruce to preferentially exploit upper soil layers in mixedwood stands, resulting in wider root systems. This research contrasted white spruce fine root (diameter <2 mm) distributions in organic layers of white spruce and mixedwood stands. Research occurred at the Fallingsnow Ecosystem Project site in northwestern Ontario. Eighteen plots represented mixedwood and pure white spruce stands. Trees were mapped; foliage and root samples were collected. Roots were separated by species and scanned to determine length. Simple sequence repeat DNA profiles were determined for all white spruce trees and for 45 white spruce root fragments per plot. Root and tree DNA profiles were matched; corresponding distances were calculated. Most (80%) root fragments were within 3.2 m of tree stems. Root prevalence decreased rapidly with distance. Organic layer pH was significantly less acidic in mixedwood plots, but only in one block. A subtle significant trend towards wider root distributions occurred in mixedwood stands.