Grapevine Diversity and Genetic Relationships in Northeast Portugal Old Vineyards

More than 100 grapevine varieties are registered as suitable for wine production in “Douro” and “Trás-os-Montes” Protected Designations of Origin regions; however, only a few are actually used for winemaking. The identification of varieties cultivated in past times can be an important step to take advantage of all the potential of these regions grape biodiversity. The conservation of the vanishing genetic resources boosts greater product diversification, and it can be considered strategic in the valorisation of these wine regions. Hence, one goal of the present study was to prospect and characterise, through molecular markers, 310 plants of 11 old vineyards that constitute a broad representation of the grape genetic patrimony of “Douro” and “Trás-os-Montes” wine regions; 280 samples, grouped into 52 distinct known varieties, were identified through comparison of their genetic profiles generated via 6 nuclear SSR and 43 informative SNP loci amplification; the remaining 30 samples, accounting for 13 different genotypes, did not match with any profile in the consulted databases and were considered as new genotypes. This study also aimed at evaluating the population structure among the 65 non-redundant genotypes identified, which were grouped into two ancestral genetic groups. The mean probability of identity values of 0.072 and 0.510 (for the 6 SSR and 226 SNP sets, respectively) were determined. Minor differences were observed between frequencies of chlorotypes A and D within the non-redundant genotypes studied. Twenty-seven pedigrees were confirmed and nine new trios were established. Ancestors of eight genotypes remain unknown.

Genetic Evidence of Stable Northward Extension of Pinus Thunbergii Forests in the Democratic People’s Republic Korea

Japanese black pine with high salt tolerance may be an important constitutive element sustaining terrestrial ecosystem by playing a role of windbreak forests in coastal areas. Korean peninsula would be a notable region in clarifying distribution shift in Pinus species as it has northern distribution limit of Japanese black pine in Asia. Our main object was to verify genetic evidence of stable northward extension of P.thunbergii populations in D. P. R. Korea. We investigated genetic background of 9 populations existing in Korean peninsula using nuclear SSR markers in relation to shifts in climate factors such as temperature and precipitation. Higher genetic diversity in east group (AR=10.7~19.5) and west group (AR=10.3~10.7) compared to north group (AR=6.7~8.8) was found. When number of putative clusters (K) = 2, whole individuals were divided into west group and north-east group, and when K=3, north-east group can be separated into north group and east group. Phylogeographic relationship verified by means of nSSR markers suggest that substantial increment of air temperature in D. P. R. Korea allowed stable anthropogenic transfer of P.thunbergii forests and that artificial afforestation may bring rapid establishment of forest ecosystem owing to climate change.

Developing and Testing Molecular Markers in Cannabis sativa (Hemp) for Their Use in Variety and Dioecy Assessments

Cannabis sativa (2n = 2x = 20) is a popular species belonging to the Cannabaceae family. Despite its use for medical, recreational, and industrial purposes as well as its long history, the genetic research on this species is in its infancy due to the legal implications and the prohibition campaigns. The recent legalization of Cannabis in many countries along with the use of genomics boosted the approaches aimed at marker-assisted selection, germplasm management, genetic discrimination, and authentication of cultivars. Nonetheless, the exploitation of molecular markers for the development of commercial varieties through marker-assisted breeding schemes is still rare. The present study aimed to develop an informative panel of simple sequence repeat markers to be used for the genotyping of high breeding value C. sativa lines. Starting from 41 nuclear SSR designated by in silico analyses, we selected 20 highly polymorphic and discriminant loci that were tested in 104 individuals belonging to 11 distinct hemp varieties. The selected markers were successful in accessing homozygosity, genetic uniformity, and genetic variation within and among varieties. Population structure analysis identified eight genetic groups, clustering individuals based on sexual behaviors (dioecious and monoecious) and geographical origins. Overall, this study provides important tools for the genetic characterization, authentication, conservation of biodiversity, genetic improvement and traceability of this increasingly important plant species.

How the Virtual Thinning Can Help to Control the Changing of Genetic Structure in Scots Pine Stands?

The work detailed here in the context of the above project sought to determine changes in the gene pool (at the DNA level) in a stand of Scots pine (Pinus sylvestris L.), under the influence of various kinds of forest-tending cuts. The experimental area on which the research was focused is located in Poland’s Ostrów Mazowiecka Forest District. Genetic structure was specified using five nuclear SSR sequences and six chloroplast SSR loci, while the five thinning variants trialled were sanitation cutting, low thinning of 30% intensity, schematic thinning, selective thinning and destructive lumbering. The control variant was left untreated. It was virtual rather than real-life thinning that was pursued, using the ForestSimulator BWINPro program. Changes in the structure of the stand after a further 10 years were also simulated. The different thinning variants were shown to cause change in the gene pool and level of genetic diversity of trees in the study area. In terms of maintaining genetic variability in the stand, the least-favourable method proved to be thinning from below. Destructive selection cutting was in turn most beneficial in terms of the preservation of genetic structure, with the reduction in rare alleles being more limited than in any other analysed variant. It was with the selective thinning variant that the final number of trees, stand structure and level of genetic variation resembled the situation in the control most closely. This suggests that selective thinning provides for a rather accurate replication of processes occurring in nature.

Multiple founder events explain the genetic diversity and structure of the model allopolyploid grass Brachypodium hybridum in the Iberian Peninsula hotspot

Background and Aims It is accepted that contemporary allopolyploid species have originated recurrently, but very few cases have been documented using multiple natural formations of the same species. To extend our knowledge, we have investigated the multiple origins, genetic variation, and structure of the allotetraploid grass Brachypodium hybridum with respect to its progenitor diploid species B. distachyon (D genome) and B. stacei (S genome). For this, our primary focus is the Iberian Peninsula, an evolutionary hotspot for the genus Brachypodium. Methods We analysed 342 B. hybridum individuals from 36 populations using 10 nuclear SSR loci and two plastid loci. The B. hybridum genetic profiles were compared with those previously reported for B. stacei and B. distachyon. In addition, phylogenetic analysis of the plastid data was performed for a reduced subset of individuals. Key Results The nuclear SSR genetic analysis detected medium to high genetic diversity, with a strong south-to-north genetic structure cline, and a high selfing rate in B. hybridum. Comparative genetic analysis showed a close relatedness of current B. hybridum D allelic profiles with those of B. distachyon, but a lack of similarity with those of B. stacei, suggesting another B. stacei source for the B. hybridum S alleles. Plastid analysis detected three different bidirectional allopolyploidization events: two involved distinct B. distachyon-like ancestors and one involved a B. stacei-like ancestor. The Southeastern (SE) Iberian Peninsula B. hybridum populations were more genetically diverse and could have originated from at least two hybridization events whereas Northeaster-Northwestern (NE-NW) Iberian Peninsula B. hybridum populations were less diverse and may have derived from at least one hybridization event. Conclusions The genetic and evolutionary evidence support the plausible in situ origin of the SE and northern Iberian Peninsula B. hybridum allopolyploids from their respective local B. distachyon and unknown B. stacei ancestors. The untapped multiple origins and genetic variation detected in these B. hybridum populations opens the way to future evolutionary analysis of allopolyploid formation and genomic dominance and expression in the B. hybridum – B. distachyon – B. stacei grass model complex.