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‘Broma’ is a grass cultivar belonging to the species Bromus carinatus. In the Lists of Agricultural Plant Varieties of the Research Centre for Cultivar Testing (COBORU), it is shown as Bromus willdenowii (= B. catharticus, B. unioloides) (List of Agricultural Plant Varieties 1989-2009), whereas already in 1984 Mirek demonstrated on the basis of morphological analysis that this was a different closely related species – B. carinatus. The aim of the present study was to verify the species affiliation of cv. ‘Broma’. The conducted analysis of ISSR molecular markers included representatives of cv. ‘Broma” as well as of B. carinatus and B. willdenowii. The method used allowed the identification of molecular markers of the above-mentioned taxa. The numerical analysis of the obtained results suggests that cv. ‘Broma’ should be classified in the species B. carinatus, not B. willdenowii.
The genus Bromus subgen. Festucaria is a widespread Old World and New World taxon having genomes A, B and L, distinguished cytogenetically. Stebbins (1981) suggested that evolution in Bromus went from the small genomes A and B to the large genome L. Thus, Old World species with genomes A and B could be ancestral to New World species with genome L. To test this hypothesis we carried out RAPD analysis of a representative group of species from subgen. Festucaria. RAPD band patterns enabled resolution of 13 species after excluding the species-specific bands with high/moderate support. The basal position of Bromus variegatus M. Bieb. - an Old World species presumably having a B genome - in relation to some New World species with the genome L confirmed Stebbins' hypothesis of its ancestry in relation to the Old World species. The group of high bootstrap support, B. cappadocicus Boiss. et Balansa-B. erectus Huds.-B. riparius Rehm., with genome A. and a distinctly xerothermic ecological profile, was related to a New World species with genome L, B. auleticus Trin. ex Nees, pointing to their presumably common evolutionary history.
Pochodzenie obecnych zasięgów oraz występowanie mieszańców międzygatunkowych jest istotne w odniesieniu do gatunków Bromus erectus i Bromus inermis, a prezentowana praca jest wstępną próbą wyjaśnienia tych problemów w oparciu o techniki molekularne (RAPD i ISSR) oraz analizę numeryczną uzyskanych danych. W badaniach wykorzystano okazy obu gatunków pochodzące z wybranych, naturalnych stanowisk z terenu Polski i Ukrainy oraz z kolekcji IHAR w Bydgoszczy, a także ich mieszańce ze stanowiska na Podolu (Ukraina). Przeprowadzone badania wykazały wyraźne różnice między populacjami B. inermis z obszaru Polski Zachodniej oraz Polski Wschodniej i Podola. Zróżnicowania takiego nie obserwowano w przypadku B. erectus. Analiza gatunkowo-specyficznych markerów molekularnych pozwoliła na potwierdzenie mieszańcowego charakteru niektórych okazów.
The tetraploid (2n = 32) Aconitum sect. Aconitum in the Eastern Carpathians, Southern Carpathians and Apušeni Mts. is represented by high-mountain A. bucovinese, A. firmum subsp. fissurae and their putative taxonomic hybrid A. ×nanum. The aim of the paper was to reveal which delimiting system: taxonomic vs.geographic-population better explains genetic variability (ISSR — Inter Simple Sequence Repeats) of the Aconitum individuals in the Eastern/Southern Carpathians. Twenty nine plants sampled in five populations within entire range of taxa distribution were assigned to genetic groups according to a Bayesian STRUCTURE analysis, neighbour-net classification (NN), and nonmetric multidimensional scaling ordination (NMDS). Three taxa were distributed in four (NN, NMDS) or two (STRUCTURE) genetic groups, and the partitioning of genetic variation with analysis of molecular variance (AMOVA) revealed the highest percentage of variation attributed to the four ISSR genetic groups (22.6%), then to the two STRUCTURE groups (18.9%) and three taxa (15.6%, all P < 0.001), and finally to the three geographic regions (6.5%, P = 0.013). Genetic groups harbored specimens from distant regions: A. f. subsp. fissurae had similar genetic profiles in the Southern Carpathians and Apušeni Mts. (100% support), and some specimens of A. bucovinense had genetic links with A. f. subsp. fissurae. The hybrid species A. ×nanum was genetically specific. We concluded that (i) genetic links between nowadays distantly located populations could have originated in the effect of ancient contacts and hybridization, (ii) probably in the Carpathians two ancient genetic centers of the A. sect. Aconitum existed and (iii) high genetic specificity of the hybrid species A. ×nanum deserves further studies.
Aconitum lasiocarpum (Carpathian endemic) and A. variegatum (European endemic) occur sympatrically in the Polish Western Carpathians. Here their taxonomic hybrid A. ×pawlowskii occurs. The aim of this study was to determine the relationship between the taxonomic (Linnaean approach) and genetic structure (PCR-ISSR analysis) of the populations and individuals in two allopatric and four sympatric populations. We determined 309 individuals (OTUs) to species, subspecies and nothospecies using the Linnaean system of classification, and then genetically fingerprinted 39 randomly chosen OTUs. Comparison of the Nei and Li distances obtained from ISSR and morphological matrices using the Mantel test indicated a significant correlation (n = 39, r = 0.53, P = 0.001). Genetic analysis (NEWHYBRIDS) pointed to 7 OTUs as being later-generation hybrids (B1 introgessants) in the sympatric area. Five of them belong to A. variegatum, indicating cryptic introgression, and two belong to A. ×pawlowskii. Nonmetric multidimensional scaling (NDMS) showed gene flow between A. lasiocarpum and A. ×pawlowskii. Allopatric, morphologically pure A. lasiocarpum and A. variegatum populations differed significantly in their ISSR profiles (Fischer's R×C test, P < 0.0001). Expected heterozygosity (Hj) was significantly (p=0.05) lower in allopatric (0.1261–0.1268) than in sympatric populations (0.1348–0.1509), indicating a genetic melting pot in sympatry. The results support the existence of a natural interspecific hybrid swarm zone in the sympatric area of occurrence of Aconitum, and the taxonomic circumscription of the nothospecies within the Linnaean taxonomic system.
RAPD analysis was applied to nine Bromus species (B. fasciculatus, B. arvensis, B. scoparius, B. hordeaceus, B. squarrosus, B. carinatus, B. willdenowii, B. erectus, B. inermis) belonging to four subgenera: subg. Stenobromus, subg. Bromus, subg. Ceratochloa, and subg. Festucaria. With 10 out 13 primers a considerable degree of polymorphism was detected at the interspecific level, and some bands obtained with these primers appeared to be species-specific. The RAPD band distribution and genetic relationships between different Bromus species and subgenera were analyzed. No bands common to all analyzed species were discovered, but some of the amplified DNA fragments were common to all taxa belonging to the same subgenera or even different ones. The divisions suggested by taxonomists generally were confirmed by numerical analysis of the RAPD data presented here.
Aconitum bucovinense, a high-mountain species endemic to the Eastern and Southern Carpathians, including the Apuseni Mountains, is legally protected and classified in the Polish Red Data Book of Plants. It attains its NW geographical range in two peripheral populations in the Western Bieszczady Mountains (Polish Eastern Carpathians), isolated by a distance of 13.1 km. PCR-ISSR analysis has been used to elucidate the within- and among-populational levels of species genetic diversity. A UPGMA and block clustering showed discreteness of the populations and subpopulations based on ISSR banding pattern. Analysis of Molecular Variance (AMOVA) revealed significant divergence (P = 0.024) of the two marginal populations and highly significant (P < 0.001) differentiation of subpopulations within populations. The theta index calculated for the two marginal populations and the core population in the Carpathians was 0.131 ±0.030 S.D. Most of the population-genetic diversity indices of the mar­ginal populations were not different from those in the core area but the Shannon’s and rarity indices were lower in the marginal populations. It seems that founder effect and subsequent genetic bottleneck resulted in a fine-scale population genetic structure. The marginal populations under study need a relevant recovery program to maintain their genetic diversity.
The co-occurrence of hybrids and parental species in similar ecological niches poses a question on the role of traits additivity and overdispersion (emergence of new traits) in microevolutionary processes. We analysed genetic polymorphism of Bromus benekenii, B. ramosus and the spontaneous hybrid B. benekenii × B. ramosus in sympatric and allopatric parts of the species distribution in Europe, based on non-coding regions of the taxon genomes (ISSR genetic fingerprinting). We tested 68 individuals in 7 populations, including a hybrid population in N France. Altogether 233 polymorphic ISSR bands (loci) were obtained. We found that the parent species were genetically distinct and the hybrids had an additive pattern of ISSR bands found in the putative parental species (NMDS, STRUCTURE); however, there was evidence of introgression towards B. ramosus (NEWHYBRIDS, UPGMA classifications, Nei's D genetic distance). Bromus benekenii had 72, B. ramosus 21 and the hybrids 9 private bands (genetic overdispersion), probably resulting from the rearranged genomes. Based on its low genetic divergence index DW, the hybrid population seems to be at a young age. We argue that in the face of anthropogenic landscape transformations favouring secondary contacts, the hybrids may competitively replace the parental species in sympatric areas.
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