Evidence for continual hybridization rather than hybrid speciation betweenLigularia duciformisandL. paradoxa(Asteraceae)

BackgroundHybrids possess phenotypic traits that are often intermediate between their parental taxa, which commonly serves as evidence of hybridization in morphological analyses. Natural hybridization has been shown to occur frequently inLigularia(Asteraceae). In a previous study,Ligularia×maoniushanensiswas demonstrated as a natural hybrid species betweenL. duciformisandL.paradoxabased on morphological and reproductive traits.MethodsWe used three chloroplast (cpDNA) fragments (psbA-trnH,trnL-rpl32 andtrnQ-5′rps16), the nuclear ribosomal internal transcribed spacer (nrITS), and co-dominant SSR and dominant ISSR markers to study natural hybridization betweenL. duciformisandL. paradoxagrowing sympatrically in two locations. Parental taxa were inferred using network analyses of cpDNA and nrITS haplotypes. Admixture among individuals was examined using the Bayesian clustering programs STRUCTURE and NewHybrids based on the SSR and ISSR data; and potential introgression in the SSR loci was assessed using the INTROGRESS package.ResultsThe putative parental species were clearly distinguished from other sympatricLigulariaspecies by nrITS data, andL.×maoniushanensisindividuals were confirmed to be the hybrid offspring ofL.duciformisandL.paradoxa. Moreover, introgression was detected among several individuals morphologically identified asL.duciformisorL. paradoxa. Analyses of the cpDNA data revealed primarily unidirectional hybridization betweenL. duciformisandL. paradoxa, withL.paradoxaas the maternal parent in Mt. Maoniu, whereas bidirectional but asymmetrical hybridization was inferred to occur in Heihai Lake. The STRUCTURE analyses based on the SSR data detected two distinct clusters among the three taxa. The NewHybrids analyses showed that individuals circumscribed asL.×maoniushanensiswere dominated by early- and later-generation and backcrossing hybrids. The NewHybrids results based on the ISSR data were congruent with SSR results. In addition, introgression was detected in some SSR loci, and heterogeneity among loci was found in terms of detected patterns of introgression.ConclusionsOur data provide strong evidence for hybridization and introgression betweenL.duciformisandL.paradoxa.Ligularia×maoniushanensiswas demonstrated to be of hybrid origin. Since no evident reproductive isolation was found between the two parental species, detected hybrids appear to be part of hybrid swarms resulting from frequent and ongoing gene flow, which might impede the formation of a new hybrid species.

Download Full-text

Natural hybridization between two butterfly bushes in Tibet: dominance of F1 hybrids promotes strong reproductive isolation

10.21203/rs.3.rs-42245/v2 ◽

2020 ◽

Author(s):

Rongli Liao ◽

Weibang Sun ◽

Yongpeng Ma

Keyword(s):

Reproductive Isolation ◽

Parental Species ◽

Morphological Characters ◽

Natural Hybridization ◽

Hybrid Origin ◽

F1 Hybrids ◽

Evolutionary Significance ◽

Sympatric Populations ◽

Hybrid Species ◽

Intergenic Spacers

Abstract Background: F1 hybrids acting as a bridgehead for producing later generation hybrids can have evolutionary significance through strengthening reproductive isolation or facilitating gene flow between parental species, depending on whether backcrossing can occur. It had been suggested that the Tibetan plant Buddleja wardii was a hybrid species between B. alternifolia and B. crispa based on their sympatric distributions and the morphological characters in last century. Till now however, we still have limited evidence to prove key issues to B. wardii, like if it is of hybrid origin indeed and whether it is currently a true hybrid species already.Results: In the present study, two sympatric populations of these three taxa were examined and compared using four nuclear genes and three chloroplast intergenic spacers, as well as with 10 morphological characters. Our results suggest that at both sites B. × wardii was likely to be a hybrids between B. alternifolia and B. crispa, and moreover, most of the hybrids present were confirmed to be F1s. This was further supported by morphology as no transgressive characters were detected. B. crispa was found to be the maternal parent in one population (BH), while in the second population (TJ), it was difficult to distinguish the hybridization direction due to shared haplotypes of cpDNA between B. alternifolia and B. crispa. Conclusions: These results provide evidence that the natural hybrids between B. alternifolia and B. crispa mainly comprise F1 hybrids, which have subsequently been given the name B. wardii. The F1 hybrids have also contributed to strong reproductive isolation between parental species.

Download Full-text

Natural Hybridization between Two Butterfly Bushes in Tibet: Dominance of F1 Hybrids Promotes Strong Reproductive Isolation

10.21203/rs.3.rs-42245/v1 ◽

2020 ◽

Author(s):

Rongli Liao ◽

Weibang Sun ◽

Yongpeng Ma

Keyword(s):

Reproductive Isolation ◽

Parental Species ◽

Morphological Characters ◽

Natural Hybridization ◽

Hybrid Origin ◽

F1 Hybrids ◽

Evolutionary Significance ◽

Sympatric Populations ◽

Hybrid Species ◽

Intergenic Spacers

Download Full-text

Molecular evidence of the hybrid origin of Cryptocoryne ×purpurea Ridl. nothovar. purpurea (Araceae)

PLoS ONE ◽

10.1371/journal.pone.0239499 ◽

2021 ◽

Vol 16 (1) ◽

pp. e0239499

Author(s):

Rusly Rosazlina ◽

Niels Jacobsen ◽

Marian Ørgaard ◽

Ahmad Sofiman Othman

Keyword(s):

Parental Species ◽

Peninsular Malaysia ◽

Natural Hybridization ◽

Nuclear Ribosomal Dna ◽

Hybrid Origin ◽

Distribution Area ◽

Molecular Evidence ◽

Sequencing Data ◽

Sympatric Distribution ◽

Putative Hybrids

Natural hybridization has been considered a source of taxonomic complexity in Cryptocoryne. A combined study of DNA sequencing data from the internal transcribed spacer (ITS) of nuclear ribosomal DNA and the trnK-matK region of chloroplast DNA was used to identify the parents of Cryptocoryne putative hybrids from Peninsular Malaysia. Based on the intermediate morphology and sympatric distribution area, the plants were tentatively identified as the hybrid Cryptocoryne ×purpurea nothovar. purpurea. The plants were pollen sterile and had long been considered as hybrids, supposedly between two related and co-existing species, C. cordata var. cordata and C. griffithii. The status of C. ×purpurea nothovar. purpurea was independently confirmed by the presence of an additive ITS sequence pattern from these two parental species in hybrid individuals. An analysis of the chloroplast trnK-matK sequences showed that the hybridization is bidirectional with the putative hybrids sharing identical sequences from C. cordata var. cordata and C. griffithii, indicating that both putative parental species had been the maternal parent in different accessions.

Download Full-text

Interspecific Hybrid Verification of Rosa with Isozymes

HortScience ◽

10.21273/hortsci.31.7.1207 ◽

1996 ◽

Vol 31 (7) ◽

pp. 1207-1209 ◽

Cited By ~ 3

Author(s):

Young-ju Kim ◽

David H. Byrne

Keyword(s):

Acid Phosphatase ◽

Malate Dehydrogenase ◽

Interspecific Hybrid ◽

Parental Species ◽

Phosphoglucose Isomerase ◽

Hybrid Origin ◽

Hybrid Species

The hybrid origin of 23 rose (Rosa spp.) accessions was examined with three isozymes: acid phosphatase (E.C.3.1.3.2), malate dehydrogenase (E.C.1.1.1.37), and phosphoglucose isomerase (E.C.5.3.1.9). All three isozymes were useful for interspecific hybrid verification. This procedure was effective if the putative parents were known and differed in isozyme phenotype. To verify the origin of hybrid species or cultivars with hybrid origins, isozymes were useful but limited by the number of generations since the original hybridization and the number of accessions of the putative parental species assayed.

Download Full-text

Molecular evidence for the hybrid origin of Cryptocoryne ×purpurea Ridl. nothovar. purpurea (Araceae)

10.1101/2020.09.09.289165 ◽

2020 ◽

Author(s):

Rusly Rosazlina ◽

Niels Jacobsen ◽

Marian Ørgaard ◽

Ahmad Sofiman Othman

Keyword(s):

Internal Transcribed Spacer ◽

Parental Species ◽

Peninsular Malaysia ◽

Natural Hybridization ◽

Nuclear Ribosomal Dna ◽

Hybrid Origin ◽

Molecular Evidence ◽

Sequencing Data ◽

Sympatric Distribution ◽

Putative Hybrids

AbstractNatural hybridization has been considered a source of taxonomic complexity in Cryptocoryne. A combined study of DNA sequencing data from internal transcribed spacer (ITS) of nuclear ribosomal DNA and trnK-matK region of chloroplast DNA was used to identify the parents of Cryptocoryne putative hybrids from Peninsular Malaysia. Based on the morphological intermediary and sympatric distribution, the plants were tentatively identified as the hybrid Cryptocoryne ×purpurea nothovar. purpurea; plants were pollen sterile and had long been considered to be hybrids, possibly between two related and co-existing species, C. cordata var. cordata and C. griffithii. The C. ×purpurea nothovar. purpurea status was independently confirmed by the presence of an additive ITS sequence pattern from these two parental species in hybrid individuals. Analysis of the chloroplast trnK-matK sequences showed that the hybridization is bidirectional with the putative hybrids sharing identical sequences from C. cordata var. cordata and C. griffithii, indicating that both putative parental species had been the maternal parent in different accessions.

Download Full-text

Molecular evidence for the hybrid origin of Rosa lichiangensis (Rosaceae)

Phytotaxa ◽

10.11646/phytotaxa.222.3.5 ◽

2015 ◽

Vol 222 (3) ◽

pp. 221 ◽

Cited By ~ 1

Author(s):

Zhangming Zhu ◽

Xinfen Gao

Keyword(s):

Significant Role ◽

Single Copy ◽

Morphological Characters ◽

Molecular Data ◽

Natural Hybridization ◽

Hybrid Origin ◽

Molecular Evidence ◽

Nuclear Marker

Natural hybridization was assumed to play a significant role in the diversification of Rosa. Rosa lichiangensis was suspected to be of hybrid origin based on its intermediate morphological characters between R. soulieana and R. multiflora var. cathayensis. In this study, four chloroplast regions (ndhC-trnV, ndhF-rpl32, ndhJ-trnF, and psbJ-petA) and a single copy nuclear marker (GAPDH) were used to test the hybrid origin of R. lichiangensis. The results from molecular data supported the hybrid origin of R. lichiangensis and further identified R. soulieana as its maternal progenitor and R. multiflora var. cathayensis as the paternal progenitor.

Download Full-text

Genetic divergence in Agave accessions through ISSR markers and phenotypic traits

African Journal of Agricultural Research ◽

10.5897/ajar2017.12913 ◽

2018 ◽

Vol 13 (11) ◽

pp. 526-533 ◽

Cited By ~ 1

Author(s):

Chaves de Souza Silmara ◽

Jaime Vasconcelos Cavalcanti Jose ◽

Pierre Cordeiro Ramos Jean ◽

Alves Isaías ◽

Cavalcanti dos Santos Roseane ◽

...

Keyword(s):

Genetic Divergence ◽

Issr Markers ◽

Phenotypic Traits

Download Full-text

Application of Microsatellite and Inter Simple Sequence Markers for Certifying Trueness to Type of Grafted Ramets and Clustering of Persian Walnut Varieties

10.21203/rs.3.rs-542091/v1 ◽

2021 ◽

Author(s):

Masoomeh Hosseini Nickravesh ◽

Kourosh Vahdati ◽

fatemeh amini ◽

Reza Amiri ◽

Keith Woeste

Keyword(s):

Ssr Markers ◽

Issr Markers ◽

Principal Coordinate Analysis ◽

Dna Fingerprint ◽

Polymorphic Ssrs ◽

Persian Walnut ◽

Inter Simple Sequence Repeats ◽

Ssr Loci ◽

Ssrs Markers ◽

Simple Sequence

Abstract The utility of seventeen Microsatellite (SSR) markers and fifteen inter simple sequence repeats (ISSR) markers for the identification of twenty eight ramets of 11 varieties of walnut (Juglans regia) was explored. Thirty nine individual genomes were screened using 61 and 38 scorable fragments from SSR and ISSR markers, respectively. The least polymorphic SSR locus was WGA004 (two alleles) and the most polymorphic (5 alleles) was WGA276. Polymorphism information content values ranged from 0.08 (WGA004) to 0.43 (WGA032) in SSR markers and from 0.11 (AGA (AC)7) to 0.49 (CAC(TGT)5) in ISSR markers, with an average of 0.29 and 0.19, respectively. In most cases, grafted varieties with identical names also had the same microsatellites profile. The principal coordinate analysis and clustering (UPGMA) based on the combined marker set emphasized two failures in grafting or off-types, ramets identified as Serr 4 (S4) and Vina 1 (V1). The presence of two off-type ramets in the walnut research orchard emphasizes the importance of using molecular certification for proving true-to-type of walnut orchards. Using 13 polymorphic SSRs, we tabulated a DNA fingerprint chart of 11 walnut varieties. Except for ‘Chandler’, each cultivar could be distinguished using a combination of only two SSR loci. The 13 SSRs markers evaluated in this study could be used in future to identify clones produced from the varieties.

Download Full-text

Hepatica transsilvanica Fuss (Ranunculaceae) is an Allotetraploid Relict of the Tertiary Flora in Europe – Molecular Phylogenetic Evidence

Acta Societatis Botanicorum Poloniae ◽

10.5586/asbp.8934 ◽

2020 ◽

Vol 89 (3) ◽

Cited By ~ 1

Author(s):

Levente Laczkó ◽

Gábor Sramkó

Keyword(s):

Parental Species ◽

Gene Tree ◽

Diploid Species ◽

Nuclear Gene ◽

Hybrid Origin ◽

Distribution Area ◽

Recent Common Ancestor ◽

Term Survival ◽

Quaternary Glaciation ◽

Eastern Carpathians

The Hepatica section Angulosa consists of mainly tetraploid (2n = 28) species that are distributed disjunctly throughout Eurasia. Karyological evidence proves the hybrid origin of the polyploid species of this section. Hepatica transsilvanica is a member of this species group with a conspicuous distribution restricted to the Eastern Carpathians. Based on genome size and cytotypes, the paternal parent of H. transsilvanica is described to be the only diploid species in section Angulosa, H. falconeri. The maternal species is hypothesized to be H. nobilis, a European species with entirely lobed leaves and a wider distribution area. Although the hybrid origin of H. transsilvanica is well documented by karyological evidence, the time of hybridization has never been studied. By using sequences of both the nuclear and plastid genome, we reconstructed the phylogenetic relationships and divergence times of H. transsilvanica and its parental species. The identity of the parental species is corroborated by discordant gene tree topologies of the nrITS and plastid sequences. Moreover, both gene copies of the parental species could be identified with the low-copy nuclear gene, MLH1. Divergence dating analysis using Bayesian phylogenetic methods strongly supported the long-term survival of H. transsilvanica in the Southeastern Carpathians, as the most recent common ancestor of the hybrid and parent species existed not later than the beginning of the Pleistocene, ca. 3 million years ago. These results not only highlight the biogeographic importance of the Southeastern Carpathians in the Quaternary glaciation periods, but also emphasize that Tertiary lineages could have survived in a Central European cryptic refugium.

Download Full-text

Hybridization between the threatened herb Boltonia decurrens (Asteraceae) and its widespread congener, B. asteroides

Botany ◽

10.1139/b11-005 ◽

2011 ◽

Vol 89 (3) ◽

pp. 191-201

Author(s):

Jennifer DeWoody ◽

John D. Nason ◽

Marian Smith

Keyword(s):

Parental Species ◽

Backcross Progeny ◽

Illinois River ◽

Morphological Data ◽

Hybrid Origin ◽

Sympatric Population ◽

Closely Related Species ◽

Low Frequencies ◽

Marker Data ◽

Boltonia Decurrens

Boltonia decurrens (Torr. & A. Gray) A. Wood is a federally threatened herb endemic to the Illinois River floodplain, and currently restricted to fewer than 25 populations. We tested for hybridization between this species and a widespread congener, Boltonia asteroides (L.) L’Hér., at two sites where they are known to occur in sympatry, by comparing morphological and genetic diversity with an allopatric population of each species. Morphological analyses identified significant differentiation between species. Discriminant classification analysis of the morphological data assigned most individuals to one or the other of the two parental species with high probability (>0.95), with only four plants having an intermediate probability of assignment (<0.90) indicative of hybrid origin. Similarly, likelihood-based methods based on genetic marker data (allozymes) failed to detect the presence of F1 hybrids in either sympatric population and revealed only low frequencies of F2 and backcross progeny. These findings demonstrate that combining morphological and genetic data increases the likelihood of detecting low-scale introgression between closely related species. Even with this combined approach, the low rate of recombination between these species together with their limited sympatry indicate that hybridization does not pose an immediate threat to the genetic integrity of B. decurrens.

Download Full-text