© iForest -Biogeosciences and Forestry © SISEF http://www.sisef.it/iforest/ 324 iForest (2015) 8: 324-332 Citation: Curtu AL, Craciunesc I, Enescu CM, Vidalis A, Sofletea N, 2015. Fine-scale spatial genetic structure in a multi-oak-species (Quercus spp.) forest. iForest 8: 324-332 [online 2014-09-05]Patterns of fine-scale spatial distribution of multilocus genotypes can provide valuable insights into the biology of forest tree species. Here we tested for the existence of spatial genetic structure (SGS) in a four-oak-species forest with contrasting species abundances and hybridization rates. A total of 483 adult trees were mapped over 8.6 ha and genotyped using 10 highly polymorphic genomic regions. A weak but significant SGS was observed in each of the four oak species, with Quercus frainetto, the species with the lowest density in the sampling plot, exhibiting the strongest SGS. The values of the Sp statistic were 0.0033, 0.0035, 0.0042, and 0.0098 for Q. petraea, Q. robur, Q. pubescens, and Q. frainetto, respectively. The spatial correlogram of the total population was significantly different when hybrids were removed from the analysis, which suggests that hybridization influenced the SGS. Interspecific SGSs were significantly correlated with the rates of hybridization. Implications of the obtained results for the conservation and management of forest genetic resources are discussed. iForest 8: 324-332 325 © SISEF http://www.sisef.it/iforest/ iForest 8: 324-332 329 © SISEF http://www.sisef.it/iforest/

In Europe, most of the alpine timberline ecotone has been altered by human activities and climate change. Hence, mountain forests are of the highest conservation interest. Here, we screened 25 populations of Swiss stone pine (Pinus cembra L.) from the Carpathians and the Alps, using a set of ten microsatellite primers to assess the relative conservation value of populations sampled in Polish and Slovak Tatra National Parks, where potential extinction risk is the highest within the Carpathian range. Although endangered, with small and fragmented populations, P. cembra in the Tatra Mts. shows high levels of allelic richness (AR = 5.0) and observed heterozygosity (H o = 0.554). Our results suggest that anthropogenic habitat fragmentation has had little impact on DNA variation of Swiss stone pine in the Tatra Mts. However, the effects of changing conditions on the genetic structure may occur with a substantial time delay due to the long life span of P. cembra. Moreover, inbreeding depression may occur in the next generations, since we found inbreeding (F IS = 0.063) and elevated coancestry coefficient (h = 0.062) in all populations. Also a shallow pattern of genetic differentiation between populations was found, indicating recent fragmentation of a common gene pool that formerly occupied a larger range. Therefore, the Tatra Mts. can be considered as a single conservation unit. Based on our results, we suggest possible conservation activities for Swiss stone pine both in Poland and Slovakia.

2-Morpholine-4ylethyl-3 H -1,2,4-triazole-3-ones (2a, 2b) were obtained from the condensation between the corresponding ethoxycarbonylhydrazones and 2-morpholinoethanamine. 2a was converted to acetohydrazide (4) via the formation of an ester derivative (3). Treatment of 2a and 2b with several aryl sulfonyl chlorides afforded the corresponding 2-arylsulfonyl-1,2,4-triazole-3-ones (5a-c and 6). The reaction of hydrazide (4) with benzyl iso-and benzyl isothiocyanate produced the corresponding carboxamide (8a) and carbothioamide (8b). The basic treatment of 8b yielded 5-mercapto-4 H -1,2,4-triazol-3yl)methyl]-2,4-dihydro-3 H -1,2,4-triazol-3-one (10). The synthesis of 1,3-thiazol-2(3 H) -ylidene-1,2,4-triazol-1-ylacetohydrazide (11) and 1,3-oxazole-2(3 H) -ylidene-1,2,4-triazole-1-yl)acetohydrazide ( 9) derivatives was performed from the reaction of 8a and 8b with substituted phenacyl bromides.All the newly synthesized compounds were screened for their antimicrobial activities and some of them were found to possess good or moderate antimicrobial activity.

Landscape genetics is increasingly being used in landscape planning for biodiversity conservation by assessing habitat connectivity and identifying landscape barriers, using intraspecific genetic data and quantification of landscape heterogeneity to statistically test the link between genetic variation and landscape variability. In this study we used genetic data to understand how landscape features and environmental factors influence demographic connectedness in Europe’s largest brown bear population and to assist in mitigating planned infrastructure development in Romania. Model-based clustering inferred one large and continuous bear population across the Carpathians suggesting that suitable bear habitat has not become sufficiently fragmented to restrict movement of individuals. However, at a finer scale, large rivers, often located alongside large roads with heavy traffic, were found to restrict gene flow significantly, while eastern facing slopes promoted genetic exchange. Since the proposed highway infrastructure development threatens to fragment regions of the Carpathians where brown bears occur, we develop a decision support tool based on models that assess the landscape configuration needed for brown bear conservation using wildlife corridor parameters. Critical brown bear corridors were identified through spatial mapping and connectivity models, which may be negatively influenced by infrastructure development and which therefore require mitigation. We recommend that current and proposed infrastructure developments incorporate these findings into their design and where possible avoid construction measures that may further fragment Romania’s brown bear population or include mitigation measures where alternative routes are not feasible.

To cite this version:Alexandru Curtu, Sofletea, Alin Toader, Mihai Enescu. Leaf morphological and genetic differentiation between Quercus robur L. and its closest relative, the drought-tolerant Quercus pedunculiflora

Little is known about genetic differences among Quercus frainetto and Q. pubescens, two species of section Dascia Kotschy (subgenus Lepidobalanus, white oaks) that reach in Romania the margins of their natural distribution range. A set of genomic SSRs (simple sequence repeats) and EST (expressed sequence tags)-SSRs was used to estimate the genetic differentiation among four natural populations of the two species. Q. pubescens had higher values of genetic diversity than Q. frainetto, although the differences were not significant. Two out of seven marker-loci, QrZAG112 and QpZAG110, displayed very high FST values. Averaged across loci, the genetic differentiation was high and significant (FST = 0.067). Genetic distances were much higher among species than among populations within species. A Bayesian analysis indicated that two is the most appropriate number of genetic clusters. Using a blind procedure (i.e. based on multilocus genotypes only) the vast majority of sampled individuals (90%) could be assigned to the cluster corresponding to their phenotypes. When information about sampling localities was introduced in the assignment test, all individual trees were correctly classified. The higher degree of admixture in Q. frainetto as compared to Q. pubescens may be explained by different rates of introgressive hybridization.

Small, isolated populations are more vulnerable to natural disturbances and loss of genetic diversity. Scots pine, an abundant tree species in the boreal forest of Eurasia, has a scattered natural distribution across Eastern and Southern Carpathian Mountains, where only a few relict populations still exist. We estimated genetic diversity and spatial genetic structure in Scots pine on the basis of microsatellite nuclear markers (nSSR) data. We found a relatively high level of genetic diversity (He = 0.697) within populations and no evidence of recent bottlenecks. Genetic diversity was lower in peat bog populations, as compared to populations that grow on rocky slopes or acidic soils and nutrient-poor sites. Population genetic structure was weak, and genetic discontinuities among populations were detected. Spatial genetic structure (SGS) was observed in nearly all Scots pine populations. The strength of SGS, quantified by Sp statistics, varied greatly among populations, ranging from 0.0011 to 0.0207, with an average of 0.01. Our study highlights that Eastern and Southern Carpathian populations still possess high within-population diversity in spite of the recent fragmentation and reduction of the Scots pine natural distribution range. We discuss the importance of spatial patterns of genetic diversity for developing strategies of conservation and sustainable use of Scots pine genetic resources in the Carpathian region.

Populations located at the periphery of the species' distribution range may play an important role in the context of climate change. These peripheral populations may contain specific adaptations as a result of extreme environmental conditions. The aim of this paper was to assess within population genetic diversity and among population differentiation in one of the most important forest tree species in Europe, European beech (Fagus sylvatica), at the eastern margins of its natural range. We analysed four peripheral, isolated populations and five core populations from the continuous natural range along the Carpathian Mountains using a set of microsatellite markers. Higher levels of genetic diversity as measured by allelic richness (7.34 vs. 6.50) and observed heterozygosity (0.71 vs. 0.59) were detected in core populations than in peripheral ones. Population differentiation was slightly higher among peripheral populations than among core, Carpathian populations. There was strong evidence of bottleneck effects in two out of the four peripheral, isolated populations. Both core, Carpathian populations and peripheral, lowlands populations share the same chloroplast haplotype suggesting a common geographical origin from the putative Moravian refuge area. Past long distance founding events with material from the Carpathian mountain chain might explain the occurrence of small, isolated beech populations towards the steppe in the south-east of Romania. Our genetic data may contribute to a better understanding of the evolutionary history of the remnants of beech scattered occurrences at the eastern margins of species' distribution range.