In this study, genetic diversity of 119 accessions of common bean (Phaseolus vulgaris) from five former Yugoslav republics constituting the western Balkans was assessed by 13 microsatellite markers. This set of markers has proven before to efficiently distinguish between bean genotypes and assign them to either the Andean or the Mesoamerican gene pool of origin. In this study, 118 alleles were detected or 9.1 per locus on average. Four groups (i.e., Slovene, Croatian, Bosnian, and Serbian) showed similarly high levels of genetic diversity as estimated by the number of different alleles, number of effective alleles, Shannon’s information index, and expected heterozygosity. Mildly narrower genetic diversity was identified within a group of Macedonian accessions; however, this germplasm yielded the highest number of private alleles. All five germplasms share a great portion of genetic diversity as indicated by the analysis of molecular variance (AMOVA). On the basis of the scored number of migrants, we concluded that the most intensive gene flow in the region exists in Bosnia and Herzegovina. Cluster analysis based on collected molecular data classified the accessions into two large clusters that corresponded to two gene pools of origin (i.e., Andean and Mesoamerican). We found that Andean genotypes are more prevalent than Mesoamerican in all studied countries, except Macedonia, where the two gene pools are represented evenly. This could indicate that common bean was introduced into the western Balkans mainly from the Mediterranean Basin. Bayesian cluster analysis revealed that in the area studied an additional variation exists which is related to the Andean gene pool. Different scenarios of the origin of this variation are discussed in the article.

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Genetic resources comprised of 953 accessions of common (Phaseolus vulgaris L.) and 47 accessions of runner (Phaseolus coccineus L.) bean from the national Slovene gene bank were characterized using fourteen morphological seed descriptors. Seeds of each accession were evaluated for six quantitative characteristics: seed length, seed thickness, seed width, seed length/width ratio, seed width/thickness ratio, and 100 or 10 seed weight. Furthermore, seeds were evaluated using eight qualitative characteristics: seed colour; number of seed colours; primary/main seed colour; predominant secondary seed colour; distribution of secondary seed colour; seed veining; seed shape; and seed colour (primary and secondary) and coat pattern. For each, common, and runner bean collection, first four components within principal component analysis explained 75.03% and 80.16% of morphological variability, respectively. Regarding Ward's method and squared Euclidian distance, three clusters with the most distinct characteristics were established for each species. The results of morphological seed characterization indicate the origin (Andean, Mesoamerican, putative hybrids between gene pools) and domestication pathways of common and runner bean. This is the first study describing morphological seed characteristics of the entire common and runner bean germplasm conserved in one of the Central European bean collections. The results obtained in this study are serving as the useful information on genetic diversity of common and runner bean accessions at the Slovene gene bank, which could be used for development of new bean varieties for studied seed characteristics.

Understanding the genetic background of drought tolerance in common bean (Phaseolus vulgaris L.) can aid its resilience improvement. However, drought response studies in large seeded genotypes of Andean origin are insufficient. Here, a novel Andean intra-gene pool genetic linkage map was created for quantitative trait locus (QTL) mapping of drought-responsive traits in a recombinant inbred line population from a cross of two cultivars differing in their response to drought. Single environment and QTL × environment analysis revealed 49 QTLs for physiology, phenology, and yield-associated traits under control and/or drought conditions. Notable QTLs for days to flowering (Df1.1 and Df 1.2) were co-localized with a putative QTL for days to pods (Dp1.1) on linkage group 1, suggesting pleiotropy for genes controlling them. QTLs with stable effects for number of seeds per pod (Sp2.1) in both seasons and putative water potential QTLs (Wp1.1, Wp5.1) were detected. Detected QTLs were validated by projection on common bean consensus linkage map. Drought response-associated QTLs identified in the novel Andean recombinant inbred line (RIL) population confirmed the potential of Andean germplasm in improving drought tolerance in common bean. Yield-associated QTLs Syp1.1, Syp1.2, and Sp2.1 in particular could be useful for marker-assisted selection for higher yield of Andean common beans.

Background: The study of weed genomics is important for the effective management of weeds to enhance crop yield. A rapid, inexpensive and high quality DNA extraction is needed for genomic and other molecular studies. Here, we describe the protocols for DNA extraction from two different parts of the Echinochloa colona plant using modi ed cetyltrimethylammonium bromide (CTAB) and a commercial kit. Results: In the study, it was observed that the DNA extracted from plant leaf tissues and dry seeds with a modi ed CTAB protocol was of good quality, with no contaminations of polysaccharides and essential oils. Quality of DNA extracted from dry seeds was comparable with that of plant leaves under both protocols. The extracted DNA from both plant parts was successfully ampli ed by PCR using the EPSPS microsatellite marker. Compared to the protocol of DNA extracted from leaf tissue, dry seeds will save time and other valuable resources. Moreover, the same protocols can be implemented for the extraction of highquality DNA for molecular studies in other plant species where a large amount of polysaccharides, secondary metabolites and essential oils are present. Conclusions: Modi ed methods of DNA extraction from dry seeds are e cient and time-saving which can be used in genotypic and other molecular approaches. High-quality DNA can be isolated from plant leaf tissues using modi ed CTAB and commercial kits, however, DNA extracted from dry seeds will save time and other valuable resources.

In South-Eastern Europe, the majority of runner-bean (Phaseolus coccineus L.) production is based on local populations grown mainly in home gardens. The local runner-bean plants are well adapted to their specific growing conditions and microclimate agro-environments, and show great morpho-agronomic diversity. Here, 142 runner-bean accessions from the five South-Eastern European countries of Slovenia, Bosnia and Herzegovina, Serbia, North Macedonia and Romania were sown and cultivated in their respective countries and characterised using 28 quantitative and qualitative morpho-agronomic descriptors for Phaseolus spp. based on inflorescences, leaves, plants, pods and seeds. For each of these morpho-agronomic descriptors, the accessions can be classified into two or three specific groups. The highest correlations were observed within the fluorescence, seed and pod traits. The highest variability, at 76.39%, was between the different countries, representing different geographic origins, while the variability within the countries was 23.61%. Cluster analysis based on these collected morpho-agronomic data also classified the accessions into three groups according to genetic origins. The data obtained serve as useful genetic information for plant breeders for the breeding of new bean varieties for further studies of the morpho-agronomic traits of the runner bean.

BackgroundCommon bean (Phaseolus vulgaris L.) is the most important food legume for direct human consumption around the world, as it represents a valuable source of components with nutritional and health benefits.ResultsWe conducted a study to define and explain the genetic relatedness and diversification level of common bean (Phaseolus vulgaris L.) germplasm from Portugal to Ukraine, along a western-to-eastern line of southern European countries, including Poland. This was based on the P. vulgaris genetic structure, and was designed to better describe its distribution and domestication pathways in Europe. Using the multi-crop passport descriptors that include geographic origin and different phaseolin types (corresponding to the Mesoamerican and Andean gene pools), 782 accessions were obtained from nine gene banks and 12 geographic origins. We selected 33 genome/ gene-related/ gene-pool-related nuclear simple sequence repeat markers that covered the genetic diversity across the P. vulgaris genome. The overall polymorphic information content was 0.800. Without specifying geographic origin, global structure cluster analysis generated 10 genetic clusters. Among the PvSHP1 markers, the most informative for gene pool assignment of the European P. vulgaris germplasm was PvSHP1-B. Results of AMOVA show that 89% of the molecular variability is shared within the 782 accessions, with 4% molecular variability among the different geographic origins along this western-to-eastern line of southern Europe (including Poland).ConclusionsThis study shows that the diversification line of the European P. vulgaris germplasm followed from the western areas of southern Europe (Portugal, Spain, Italy, Slovenia) to the more eastern areas of southern Europe. This progression defines three geographically separated subgroups, as the northern (Poland, Ukraine, Romania), southern (Albania, Bulgaria), and central (Bosnia and Herzegovina, Serbia, Hungary) areas of eastern Europe.

Analysis of gene flow between Brassica napus L. and its sexually compatible relatives that could be found in the wild in Slovenia was performed by microsatellite analysis using fifteen selected primer pairs. Genotypes included in the study were obtained from the field survey of sexually compatible relatives of B. napus in natural habitats around Slovenia and from reference collections. Two different wild species of all the presented sexually compatible relatives of B. napus were found in Slovenia, B. rapa and Sinapis arvensis. The reference genotypes included varieties and wild forms from internal collections as marketable seeds or from gene banks. Reference genotypes were represented by the following species and subspecies: B. napus ssp. napobrassica, B. napus ssp. napus, B. nigra, B. oleracea, B. rapa ssp. oleifera, Diplotaxis muralis; D. tenuifolia, Raphanus raphanistrum, R. sativus, R. sativus var. oleiformis, Rapistrum rugosum, S. alba and S. arvensis. Estimation of gene flow described by average number of migrants was 0.72 followed by 0.20 migrants. Due to the observed gene migrations, genetic drift and selection, Hardy-Weinberg equilibrium was not met. The mean number of alleles over all loci was 16.9, the average polymorphic information content was 0.43. We found four highly divergent and polymorphic loci (Na12-C08, Na10-A08, Ni3-G04b and BRMS-050) at statistically significant level (p<0.05) of gene flow detected. Over all gene diversity intra-individual among populations (0.55) was lower than inter-individual among population (0.77). The results of genetic linkages based standard genetic distance and unweighted pair group method with arithmetic mean clustering method, generally divided the genotypes in three divergent groups. Similar results were obtained by principal coordinate analysis where three main groups were constructed according to three factors. A real number of genetic clusters demonstrated a clear separation between populations, where only one was comprised from genotypes from other origins. The 30.7 % out-crossing rate of B. rapa and S. arvensis populations from filed survey represents the potential for spontaneous inter-and intra-specific gene flow under Slovenian production area