Genetic Relationships and Reproductive Traits of Romanian Populations of Silver Fir (Abies alba): Implications for the Sustainable Management of Local Populations

Abstract

Assessment of the diversity of reproductive traits and genetic variation is of great relevance to the conservation of genetic resources and management of silver fir (Abies alba) populations. We have evaluated reproductive characteristics associated with female cones and seed morphology, as well as seed germination after subjecting seeds to five storage methods, in nine Romanian populations of A. alba. The genetic diversity of the populations was assessed with 12 polymorphic simple sequence repeat (SSR) markers. We detected significant differences between populations for all reproductive traits and considerable differences in seed germination and storage methods; seed storage in wet sand was the method resulting in the highest germination in all populations. Genomic SSRs (gSSRs) were more informative on average than expressed sequence tag SSRs (EST-SSRs) in the populations studied. The nine populations were genetically diverse, with an average number of alleles (N) per SSR locus between 3.50 and 4.83. The observed heterozygosity (Ho) in the nine populations was always lower than the expected heterozygosity (He), which resulted in values of the inbreeding coefficient (Fis) between 0.261 and 0.709. Genetic distances between populations ranged between 0.077 and 0.410. The cluster analysis based on genetic distances did not group accessions according to their geographical proximity, and despite a positive trend, the correlation between geographic and genetic distances was non-significant. The results of an analysis of molecular variance (AMOVA) revealed that only 9.1% of the total molecular variance is attributable to differences between populations. This low degree of genetic differentiation between populations is confirmed by the intermingling of individuals of different populations in a principal coordinate analysis (PCoA). We found evidence of a positive relationship between He and germination, as well as a negative one between Fis and germination, suggesting that populations with low diversity and high consanguinity may have a reduced fitness and long-term viability. The results are relevant for the conservation and management of local genetic resources and populations, as well as for reforestation programmes of silver fir.

Diversitatea genetică în plantaje clonale de primă generație de brad (Abies alba Mill.) din România

“…În ciuda importanței bradului pentru silvicultura românească şi europeană, studii privind diversitatea genetică a populațiilor din toate zonele arealului natural de distribuție sunt încă rare. Primele studii, bazate pe markeri izoenzimatici (Teodosiu 2009), sau cele mai recente (Postolache et al 2014, Teodosiu et al 2019, Todea Morar et al 2020) punctează asupra considerabilei diversități genetice intrapopulaționale observate, care a permis identificarea aşa numitelor hot-spot sau zone cu potențial risc de adaptare, dat fiind nivelul scăzut de diversitate genetică, precum sunt populațiile din sud-vestul Carpaților României (Teodosiu et al 2019).…”

Biological Traits and Genetic Relationships Amongst Cultivars of Three Species of Tagetes (Asteraceae)

“…There are different studies of morphological and genetic diversity within and among species of Tagetes . The knowledge of morphological and decorative characters or useful biochemical components and their genetic variability could support new breeding programmes for different species of interest [ 31 , 32 , 33 , 34 , 35 ] as well as for marigold [ 36 ]. Genetic variation and relationships among genotypes are essential in classifying and utilising germplasm resources in marigold breeding [ 37 ].…”