The cultivation of common beans has long been integral to rural economies in Italy, particularly in mountainous regions along the Apennine ridge, where the production focuses on local landraces grown by smallholder farmers using low-input methodologies. However, recent socioeconomic changes in rural communities pose a threat of genetic erosion to these landraces. This study examines the genetic diversity, structure, and uniqueness of common bean landraces in the Aniene Valley of the Lazio region to develop preservation strategies. Seventy-three accessions were investigated using morphological (seed traits), biochemical (phaseolin and phytohemagglutinin patterns), and molecular (microsatellite loci) analyses. These analyses revealed significant genetic variability within morphologically uniform seed materials and highlighted cases of homonymy and the inadvertent introduction of foreign genetic material. Among the 292 samples analyzed (four per accession), a clear differentiation between Mesoamerican and Andean gene pools was observed, with the Andean pool being predominant. Despite high levels of homozygosity and uniform seed morphotypes, genetic variability was detected in sixteen of the twenty-one landraces, suggesting that analyzing only a single or few plants per landrace may yield incomplete genetic information. The extensive morphological, biochemical, and genetic characterization of the P. vulgaris collection from the Aniene Valley provides insights for planning effective conservation strategies. These findings emphasize the importance of both in situ/on-farm and ex-situ conservation to preserve the genetic diversity and heritage of these local landraces.

This study aimed to characterize the genetic diversity and morphological traits of 32 populations of Phaseolus coccineus collected from the Aniene Valley. Quantitative seed trait analyses revealed that Mandolone accessions exhibited significantly higher seed weights and dimensions compared to Fagiolone accessions. Specifically, Mandolone accessions showed an average weight of 189.48 g per 100 seeds, with seed heights and lengths averaging 14.38 mm and 23.84 mm, respectively. In contrast, Fagiolone accessions had an average seed weight of 174.13 g, with seed heights and lengths of 13.95 mm and 22.58 mm, respectively. Molecular analysis, conducted using 9 polymorphic SSR loci, identified 53 alleles across 320 genotypes, with a mean expected heterozygosity (He) of 0.695. This indicated that there was high genetic variability within the Aniene Valley populations. The genetic diversity analysis revealed two genetic clusters corresponding to the Mandolone and Fagiolone landraces. This was supported by UPGMA, PCoA, and STRUCTURE analyses. This study highlights the need to conserve the genetic diversity within these landraces and provides a basis for the development of conservation strategies for P. coccineus germplasms in the singular ecological context of the Aniene Valley.

Sweet chestnut (Castanea sativa Mill.) coppice forests are important Mediterranean resources, but the genetic structure of local coppice stands remains insufficiently characterized, limiting their use as reference systems for wood provenance studies. This study integrated population genetic analysis, optimization of wood-derived DNA recovery, and reference-based assignment to evaluate Lazio coppice stands and test the declared origin of timber samples. Four Lazio populations were genotyped at 12 SSR loci, screened for Hardy–Weinberg disequilibrium, null alleles, and kin structure, and compared with eight European/Mediterranean populations using five shared loci. DNA extraction from dried wood was optimized through a CTAB-PEG workflow, and 40 timber samples from four sawmills, including two declared from Lazio (MCt and RPt), one from Calabria (CALt) and one from France (FRAt), were assigned using supervised DAPC, STRUCTURE with population information and GDA_NT Bayesian assignment and exclusion testing. Lazio stands retained high SSR diversity but showed heterozygote deficiency and fine-scale family structure; therefore, a conservative post-COLONY dataset was used for downstream analyses. Differentiation was weak among Lazio stands, but they showed a coherent Central Italian affinity within the available European/Mediterranean reference set. The optimized protocol yielded reproducible SSR profiles from all timber samples, with an 80.0% successful wood extraction rate. Within the available reference panel, assignment analyses indicated compatibility of MCt and RPt with a Lazio origin, whereas CALt and FRAt were incompatible with the Lazio references and should be interpreted as extra-regional or insufficiently represented by the current baseline. SSRs provide a practical first-line tool for regional chestnut timber screening, although broader reference panels and complementary high-resolution markers are needed to strengthen fine-scale provenance inference.

Sweet chestnut (Castanea sativa Mill.) is a key European forest species, widely managed in coppice systems for timber production. Despite its ecological and socio-economic relevance, regional-scale genetic structure in coppice stands and its potential application to timber traceability remain underexplored. This study aimed (i) to assess genetic diversity and population structure in four coppice chestnut stands of the Lazio region using 12 nuclear simple sequence repeat (SSR) loci, and (ii) to evaluate the feasibility of developing an SSR-based framework for timber origin verification at regional and Mediterranean scales. A total of 160 trees from four Lazio populations were genotyped and analyzed together with published SSR data from eight European populations (Spain, Piedmont, Sicily, Greece, and Turkey). Genetic diversity indices revealed high intra-population variability (mean Na = 9.17; mean He = 0.738; mean PIC = 0.737), with most genetic variation partitioned within populations (96% by AMOVA) and moderate differentiation among stands (Fst = 0.038). Bayesian clustering indicated substantial admixture, reflecting extensive gene flow and long-term connectivity typical of coppice systems. Comparative analysis using five shared SSR loci across 12 populations resolved three main phylogeographic gene pools corresponding to Iberian, Central Italian, and Eastern Mediterranean groups. To enable timber traceability, a modified CTAB–PEG DNA extraction protocol was optimized for dried wood material collected from four sawmills (Lazio, Calabria, and France). Reliable multilocus genotypes were obtained from 40 timber samples using seven highly polymorphic SSR loci. Timber assignment was conducted through an integrated analytical approach combining Discriminant Analysis of Principal Components (DAPC), Bayesian clustering (STRUCTURE), and likelihood-based exclusion testing (GDA_NT 2021). At the regional scale, timber from Lazio sawmills was consistently assigned to the corresponding reference populations with assignment scores of 1.000 and negligible exclusion probabilities. At the Mediterranean scale, timber samples were correctly affiliated with broader phylogeographic clusters, although fine-scale discrimination was limited by regional genetic homogeneity and reference coverage. These findings demonstrate that Lazio coppice stands maintain high genetic diversity and confirm the technical feasibility of SSR-based macro-regional timber traceability in C. sativa. While further marker expansion and broader geographic sampling are required for operational implementation, the integrated framework developed here provides a robust basis for genetic origin verification, supporting sustainable forest management and transparent timber supply chains.