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Sandra Knapp - One of the best experts on this subject based on the ideXlab platform.

  • a revision of the Solanum elaeagnifolium clade elaeagnifolium clade subgenus leptostemonum solanaceae
    PhytoKeys, 2017
    Co-Authors: Sandra Knapp, Eva Sagona, Anna K Z Carbonell, Franco Ezequiel Chiarini
    Abstract:

    The Solanum elaeagnifolium clade (Elaeagnifolium clade) contains five species of small, often rhizomatous, shrubs from deserts and dry forests in North and South America. Members of the clade were previously classified in sections Leprophora, Nycterium and Lathyrocarpum, and were not thought to be closely related. The group is sister to the species-rich monophyletic Old World clade of spiny Solanums. The species of the group have an amphitropical distribution, with three species in Mexico and the southwestern United States and three species in Argentina. Solanum elaeagnifolium occurs in both North and South America, and is a noxious invasive weed in dry areas worldwide. Members of the group are highly variable morphologically, and this variability has led to much synonymy, particularly in the widespread S. elaeagnifolium. We here review the taxonomic history, morphology, relationships and ecology of these species and provide keys for their identification, descriptions, full synonymy (including designations of lectotypes) and nomenclatural notes. Illustrations, distribution maps and preliminary conservation assessments are provided for all species.

  • tropical asian species show that the old world clade of spiny Solanums Solanum subgenus leptostemonum pro parte solanaceae is not monophyletic
    Botanical Journal of the Linnean Society, 2016
    Co-Authors: Xavier Aubriot, Paramjit Singh, Sandra Knapp
    Abstract:

    The tropical Asian taxa of the species-rich genus Solanum (Solanaceae) have been less well studied than their highly diverse New World relatives. Most of these tropical Asian species, including the cultivated brinjal eggplant/aubergine and its wild progenitor, are part of the largest monophyletic Solanum lineage, the ‘spiny Solanums’ (subgenus Leptostemonum or the Leptostemonum clade). Here we present the first phylogenetic analysis of spiny Solanums that includes broad sampling of the tropical Asian species, with 42 of the 56 currently recognized species represented. Two nuclear and three plastid regions [internal transcribed spacer (ITS), waxy, ndhF-rpL32, trnS-trnG and trnT-trnF] were amplified and used to reconstruct phylogenetic relationships using maximum likelihood and Bayesian methods. Our analyses show that Old World spiny Solanums do not resolve in a single clade, but are part of three unrelated lineages, suggesting at least three independent introductions from the New World. We identify and describe several monophyletic groups in Old World Solanums that have not been previously recognized. Some of these lineages are coherent in terms of morphology and geography, whereas others show considerable morphological variation and enigmatic distribution patterns. Tropical Asia occupies a key position in the biogeography of Old World spiny Solanums, with tropical Asian taxa resolved as the closest relatives of diverse groups of species from Australia and Africa.

  • a revision of the dulcamaroid clade of Solanum l solanaceae
    PhytoKeys, 2013
    Co-Authors: Sandra Knapp
    Abstract:

    The Dulcamaroid clade of Solanum contains 45 species of mostly vining or weakly scandent species, including the common circumboreal weed Solanum dulcamara L. The group comprises members of the previously recognised infrageneric groupings sect. Andropedas Rusby, sect. CaliforniSolanum A. Child, sect. Dulcamara (Moench) Dumort., sect. Holophylla (G.Don) Walp., sect. JasminoSolanum (Bitter) Seithe, sect.Lysiphellos (Bitter) Seithe, subsect. Nitidum A.Child and sect. Subdulcamara Dunal. These infrageneric groups are not monophyletic as traditionally recognised, and the complex history of the classification of the dulcamaroid Solanums is reviewed. Many of the species in the clade are quite variable morphologically; plants are shrubs, herbaceous vines or woody canopy lianas, and habits can vary between these states in a single locality. Variation in leaf shape and pubescence density and type is also extreme and has lead to the description of many minor morphological variants as distinct species. The flowers of members of the group are generally very showy, and several species (e.g., Solanum crispum Ruiz & Pav., Solanum laxum Spreng., Solanum seaforthianum Andrews) are popular ornamental plants that have occasionally escaped from cultivation and become naturalised. The clade is here divided into five morphologically and geographically delimited species groups to facilitate further study. One new species from southern Ecuador, Solanum agnoston S.Knapp sp. nov., is described here. Full descriptions and synonymies (including designations of lectotypes or neotypes), preliminary conservation assessments, illustrations, distribution maps, and an extensive list of localities are provided for all species.

  • african spiny Solanum subgenus leptostemonum solanaceae a thorny phylogenetic tangle
    Botanical Journal of the Linnean Society, 2013
    Co-Authors: Maria S Vorontsova, Lynn Bohs, Stephen R Stern, Sandra Knapp
    Abstract:

    Although most diverse in the New World tropics, approximately 100 species of Solanum (Solanaceae) are native to continental Africa and Madagascar. The majority of these are ‘spiny Solanums’ (subgenus Leptostemonum). We present here the first phylogenetic reconstruction of African and Madagascan species of Solanum subgenus Leptostemonum, with 62 of 76 species native to these areas, plus an additional seven species of largely Asian distribution, using internal transcribed spacer (ITS), waxy and trnT-F regions. We identify monophyletic groups, many of which correspond to previously recognized units, although the large, traditionally recognized sections of Oliganthes and Melongena are polyphyletic. These groups are distinguished from each other by their breeding systems, with members of Oliganthes being hermaphroditic and Melongena andromonoecious. The phylogenetic relationships suggest multiple changes of breeding system between these two states, and observations of plants across their range indicate that there is considerable lability in this character. The African and Malagasy clades are largely geographically coherent, although there is evolutionary interchange between African vegetation types. All of the Madagascan endemics included in the analysis form a coherent group and probably represent an in situ radiation. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 173, 176–193. ADDITIONAL KEYWORDS: Africa – breeding systems – eggplant – Madagascar.

  • wild relatives of the eggplant Solanum melongena l solanaceae new understanding of species names in a complex group
    PLOS ONE, 2013
    Co-Authors: Sandra Knapp, Maria S Vorontsova, Jaime Prohens
    Abstract:

    Background The common or brinjal eggplant (Solanum melongena L.) belongs to the Leptostemonum Clade (the “spiny” Solanums) of the species-rich genus Solanum (Solanaceae). Unlike most of the genus, the eggplant and its relatives are from the Old World; most eggplant wild relatives are from Africa. An informal system for naming eggplant wild relatives largely based on crossing and other biosystematics data has been in use for approximately a decade. This system recognises several forms of two broadly conceived species, S. incanum L. and S. melongena. Recent morphological and molecular work has shown that species-level differences exist between these entities, and a new species-level nomenclature has been identified as necessary for plant breeders and for the maintenance of accurately named germplasm.

Lynn Bohs - One of the best experts on this subject based on the ideXlab platform.

  • african spiny Solanum subgenus leptostemonum solanaceae a thorny phylogenetic tangle
    Botanical Journal of the Linnean Society, 2013
    Co-Authors: Maria S Vorontsova, Lynn Bohs, Stephen R Stern, Sandra Knapp
    Abstract:

    Although most diverse in the New World tropics, approximately 100 species of Solanum (Solanaceae) are native to continental Africa and Madagascar. The majority of these are ‘spiny Solanums’ (subgenus Leptostemonum). We present here the first phylogenetic reconstruction of African and Madagascan species of Solanum subgenus Leptostemonum, with 62 of 76 species native to these areas, plus an additional seven species of largely Asian distribution, using internal transcribed spacer (ITS), waxy and trnT-F regions. We identify monophyletic groups, many of which correspond to previously recognized units, although the large, traditionally recognized sections of Oliganthes and Melongena are polyphyletic. These groups are distinguished from each other by their breeding systems, with members of Oliganthes being hermaphroditic and Melongena andromonoecious. The phylogenetic relationships suggest multiple changes of breeding system between these two states, and observations of plants across their range indicate that there is considerable lability in this character. The African and Malagasy clades are largely geographically coherent, although there is evolutionary interchange between African vegetation types. All of the Madagascan endemics included in the analysis form a coherent group and probably represent an in situ radiation. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 173, 176–193. ADDITIONAL KEYWORDS: Africa – breeding systems – eggplant – Madagascar.

  • a three gene phylogeny of the genus Solanum solanaceae
    Systematic Botany, 2007
    Co-Authors: Terri Weese, Lynn Bohs
    Abstract:

    Solanum, with approximately 1,500 species, is the largest genus in the Solanaceae and includes economically important species such as the tomato, potato, and eggplant. In part due to its large size and tropical center of diversity, resolving evolutionary relationships across Solanum as a whole has been challenging. In order to identify major clades within Solanum and to gain insight into phylogenetic relationships among these clades, we sampled 102 Solanum species and seven outgroup taxa for three DNA sequence regions (chloroplast ndhF and trnT- F, and nuclear waxy) and analyzed the data using parsimony and Bayesian methods. The same major Solanum clades were identified by each data partition, and the combined analysis provided the best resolved hypothesis of relationships within the genus. Our data suggest that most traditionally recognized Solanum subgenera are not monophyletic. The Thelopodium clade is sister to the rest of Solanum, which is split into two large clades. These two large clades are further divided into at least 10 subclades, for which informal names are provided and morphological synapomorphies are proposed. The identification of these subclades provides a framework for directed sampling in further phylogenetic studies, and identifies natural groups for focused revisionary work.

  • phylogenetic relationships among the spiny Solanums Solanum subgenus leptostemonum solanaceae
    American Journal of Botany, 2006
    Co-Authors: Rachel A Levin, Nicole R Myers, Lynn Bohs
    Abstract:

    Species of Solanum subgenus Leptostemonum comprise almost one third of the genus and are distributed worldwide. Members of this group are defined by their sharp epidermal prickles; thus, they are commonly referred to as the ‘‘spiny Solanums.’’ This subgenus includes a number of economically important species such as the Old World eggplants, as well as locally cultivated New World species such as the naranjilla and cocona. Given the size and importance of this group we have examined phylogenetic relationships across subgenus Leptostemonum, including a large sampling of species from previously defined species groups within the subgenus. Evolutionary relationships were inferred using DNA sequence data from two nuclear regions (ITS and the granule-bound starch synthase gene [GBSSI or waxy]) and one chloroplast spacer region (trnS-trnG). Results suggest that Solanum subgenus Leptostemonum is monophyletic when the S. wendlandii and S. nemorense species groups are excluded. We have defined 10 clades within subgenus Leptostemonum, some of which correspond to previously circumscribed species groups or sections. Most of the Old World species of subgenus Leptostemonumbelong to a single species-rich clade. Sharp prickles and/or stellate hairs evolved more than once in Solanum, and floral heterandry originated multiple times within the ‘‘spiny Solanums.’’ waxy.

  • a four gene study of evolutionary relationships in Solanum section acanthophora
    American Journal of Botany, 2005
    Co-Authors: Rachel A Levin, Kimberly Watson, Lynn Bohs
    Abstract:

    The "spiny Solanums," Solanum subgenus Leptostemonum (Solanaceae), comprise a large lineage with over 350 species and include the cultivated eggplant, Solanum melongena. Despite the importance of this subgenus, phylogenetic relationships among these taxa are currently unclear. The present research contributes to this understanding while focusing on Solanum section Acanthophora, a group of ca. 19 species defined by the presence of simple hairs, rather than the stellate hairs common across the rest of subgenus Leptostemonum. In this study we inferred phylogenetic relationships among 29 Solanum taxa, including 14 species of section Acanthophora, using DNA sequence data from two nuclear regions (ITS and the granule-bound starch synthase gene [GBSSI or waxy]) and two chloroplast regions (trnT-trnF and trnS-trnG). This combination of gene regions resulted in a well resolved phylogenetic hypothesis, with results strongly suggesting that Solanum sect. Acanthophora is not monophyletic, although the majority of taxa comprise a monophyletic lineage that is sister to Solanum section Lasiocarpa. Of the four gene regions, waxy was especially useful for phylogenetic inference, with both a high percentage of parsimony-informative sites as well as a low level of homoplasy. Further studies in progress will help elucidate relationships of sect. Acanthophora with respect to other members of subgenus Leptostemonum.

  • phylogenetic relationships in Solanum solanaceae based on ndhf sequences
    Systematic Botany, 1997
    Co-Authors: Lynn Bohs, Richard G Olmstead
    Abstract:

    A phylogenetic analysis was conducted using sequence data from the chloroplast gene ndhF. Sequences were obtained from 25 species of Solanaceae, including 18 species of Solanum representing five of the seven conventionally recognized subgenera. Trees were constructed using parsimony and maximum likelihood methods. Results indicate that Solanum lycopersicum (formerly in genus Lycopersicon) and Solanum betaceum (formerly in genus Cyphomandra) are nested within the Solanum clade. Each of the Solanum subgenera Leptostemonum, Minon, Potatoe, and Solanum are not monophyletic as currently circumscribed. Four major clades within Solanum are supported by high bootstrap values, but the relationships among them are largely unresolved. The problematical sections Aculeigerum (represented by S. wendlandii) and Allophyllum (repre- sented by S. allophyllum) emerge as sister taxa in a larger clade composed of S. betaceum, S. luteoalbum, and members of subgenera Leptostemonum, Minon, and Solanum. Several prominent morphological characters such as spines, stellate hairs, and tapered anthers apparently have evolved more than once in Solanum.

Maria S Vorontsova - One of the best experts on this subject based on the ideXlab platform.

  • african spiny Solanum subgenus leptostemonum solanaceae a thorny phylogenetic tangle
    Botanical Journal of the Linnean Society, 2013
    Co-Authors: Maria S Vorontsova, Lynn Bohs, Stephen R Stern, Sandra Knapp
    Abstract:

    Although most diverse in the New World tropics, approximately 100 species of Solanum (Solanaceae) are native to continental Africa and Madagascar. The majority of these are ‘spiny Solanums’ (subgenus Leptostemonum). We present here the first phylogenetic reconstruction of African and Madagascan species of Solanum subgenus Leptostemonum, with 62 of 76 species native to these areas, plus an additional seven species of largely Asian distribution, using internal transcribed spacer (ITS), waxy and trnT-F regions. We identify monophyletic groups, many of which correspond to previously recognized units, although the large, traditionally recognized sections of Oliganthes and Melongena are polyphyletic. These groups are distinguished from each other by their breeding systems, with members of Oliganthes being hermaphroditic and Melongena andromonoecious. The phylogenetic relationships suggest multiple changes of breeding system between these two states, and observations of plants across their range indicate that there is considerable lability in this character. The African and Malagasy clades are largely geographically coherent, although there is evolutionary interchange between African vegetation types. All of the Madagascan endemics included in the analysis form a coherent group and probably represent an in situ radiation. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 173, 176–193. ADDITIONAL KEYWORDS: Africa – breeding systems – eggplant – Madagascar.

  • wild relatives of the eggplant Solanum melongena l solanaceae new understanding of species names in a complex group
    PLOS ONE, 2013
    Co-Authors: Sandra Knapp, Maria S Vorontsova, Jaime Prohens
    Abstract:

    Background The common or brinjal eggplant (Solanum melongena L.) belongs to the Leptostemonum Clade (the “spiny” Solanums) of the species-rich genus Solanum (Solanaceae). Unlike most of the genus, the eggplant and its relatives are from the Old World; most eggplant wild relatives are from Africa. An informal system for naming eggplant wild relatives largely based on crossing and other biosystematics data has been in use for approximately a decade. This system recognises several forms of two broadly conceived species, S. incanum L. and S. melongena. Recent morphological and molecular work has shown that species-level differences exist between these entities, and a new species-level nomenclature has been identified as necessary for plant breeders and for the maintenance of accurately named germplasm.

  • wild relatives of the eggplant Solanum melongena l solanaceae new understanding of species names in a complex group
    PLOS ONE, 2013
    Co-Authors: Sandra Knapp, Maria S Vorontsova, Jaime Prohens
    Abstract:

    Background The common or brinjal eggplant (Solanum melongena L.) belongs to the Leptostemonum Clade (the “spiny” Solanums) of the species-rich genus Solanum (Solanaceae). Unlike most of the genus, the eggplant and its relatives are from the Old World; most eggplant wild relatives are from Africa. An informal system for naming eggplant wild relatives largely based on crossing and other biosystematics data has been in use for approximately a decade. This system recognises several forms of two broadly conceived species, S. incanum L. and S. melongena. Recent morphological and molecular work has shown that species-level differences exist between these entities, and a new species-level nomenclature has been identified as necessary for plant breeders and for the maintenance of accurately named germplasm. Methodology/Principal Findings We examined herbarium specimens from throughout the wild species ranges as part of a larger revision of the spiny Solanums of Africa. Based on these morphological and molecular studies, we delimited species in the group to which the common eggplant belongs and constructed identification keys for the group. We also examined the monophyly of the group considered as the eggplant relatives by previous authors. Conclusions/Significance We recognise ten species in this group: S. aureitomentosum Bitter, S. campylacanthum A.Rich., S. cerasiferum Dunal, S. incanum L., S. insanum L., S. lichtensteinii Willd., S. linnaeanum Hepper & P.-M.L.Jaeger, S. melongena L., S. rigidum Lam. and S. umtuma Voronts. & S.Knapp. We review the history of naming and provide keys and character lists for all species. Ploidy level differences have not been investigated in the eggplant wild relatives; we identify this as a priority for improvement of crop wild relative use in breeding. The application of species-level names to these entities will help focus new collecting efforts for brinjal eggplant improvement and help facilitate information exchange.

Rachel A Levin - One of the best experts on this subject based on the ideXlab platform.

  • phylogenetic relationships among the spiny Solanums Solanum subgenus leptostemonum solanaceae
    American Journal of Botany, 2006
    Co-Authors: Rachel A Levin, Nicole R Myers, Lynn Bohs
    Abstract:

    Species of Solanum subgenus Leptostemonum comprise almost one third of the genus and are distributed worldwide. Members of this group are defined by their sharp epidermal prickles; thus, they are commonly referred to as the ‘‘spiny Solanums.’’ This subgenus includes a number of economically important species such as the Old World eggplants, as well as locally cultivated New World species such as the naranjilla and cocona. Given the size and importance of this group we have examined phylogenetic relationships across subgenus Leptostemonum, including a large sampling of species from previously defined species groups within the subgenus. Evolutionary relationships were inferred using DNA sequence data from two nuclear regions (ITS and the granule-bound starch synthase gene [GBSSI or waxy]) and one chloroplast spacer region (trnS-trnG). Results suggest that Solanum subgenus Leptostemonum is monophyletic when the S. wendlandii and S. nemorense species groups are excluded. We have defined 10 clades within subgenus Leptostemonum, some of which correspond to previously circumscribed species groups or sections. Most of the Old World species of subgenus Leptostemonumbelong to a single species-rich clade. Sharp prickles and/or stellate hairs evolved more than once in Solanum, and floral heterandry originated multiple times within the ‘‘spiny Solanums.’’ waxy.

  • a four gene study of evolutionary relationships in Solanum section acanthophora
    American Journal of Botany, 2005
    Co-Authors: Rachel A Levin, Kimberly Watson, Lynn Bohs
    Abstract:

    The "spiny Solanums," Solanum subgenus Leptostemonum (Solanaceae), comprise a large lineage with over 350 species and include the cultivated eggplant, Solanum melongena. Despite the importance of this subgenus, phylogenetic relationships among these taxa are currently unclear. The present research contributes to this understanding while focusing on Solanum section Acanthophora, a group of ca. 19 species defined by the presence of simple hairs, rather than the stellate hairs common across the rest of subgenus Leptostemonum. In this study we inferred phylogenetic relationships among 29 Solanum taxa, including 14 species of section Acanthophora, using DNA sequence data from two nuclear regions (ITS and the granule-bound starch synthase gene [GBSSI or waxy]) and two chloroplast regions (trnT-trnF and trnS-trnG). This combination of gene regions resulted in a well resolved phylogenetic hypothesis, with results strongly suggesting that Solanum sect. Acanthophora is not monophyletic, although the majority of taxa comprise a monophyletic lineage that is sister to Solanum section Lasiocarpa. Of the four gene regions, waxy was especially useful for phylogenetic inference, with both a high percentage of parsimony-informative sites as well as a low level of homoplasy. Further studies in progress will help elucidate relationships of sect. Acanthophora with respect to other members of subgenus Leptostemonum.

Jaime Prohens - One of the best experts on this subject based on the ideXlab platform.

  • diversity for chemical composition in a collection of different varietal types of tree tomato Solanum betaceum cav an andean exotic fruit
    Food Chemistry, 2015
    Co-Authors: Pablo G Acostaquezada, Jorge G Figueroa, Maria D Raigon, Tania Riofriocuenca, Maria D Garciamartinez, Mariola Plazas, Juan I Burneo, Santiago Vilanova, Jaime Prohens
    Abstract:

    Abstract We evaluated 23 tree tomato (Solanum betaceum) accessions from five cultivar groups and one wild relative (Solanum cajanumense) for 26 composition traits. For all traits we found highly significant differences (P

  • wild relatives of the eggplant Solanum melongena l solanaceae new understanding of species names in a complex group
    PLOS ONE, 2013
    Co-Authors: Sandra Knapp, Maria S Vorontsova, Jaime Prohens
    Abstract:

    Background The common or brinjal eggplant (Solanum melongena L.) belongs to the Leptostemonum Clade (the “spiny” Solanums) of the species-rich genus Solanum (Solanaceae). Unlike most of the genus, the eggplant and its relatives are from the Old World; most eggplant wild relatives are from Africa. An informal system for naming eggplant wild relatives largely based on crossing and other biosystematics data has been in use for approximately a decade. This system recognises several forms of two broadly conceived species, S. incanum L. and S. melongena. Recent morphological and molecular work has shown that species-level differences exist between these entities, and a new species-level nomenclature has been identified as necessary for plant breeders and for the maintenance of accurately named germplasm.

  • wild relatives of the eggplant Solanum melongena l solanaceae new understanding of species names in a complex group
    PLOS ONE, 2013
    Co-Authors: Sandra Knapp, Maria S Vorontsova, Jaime Prohens
    Abstract:

    Background The common or brinjal eggplant (Solanum melongena L.) belongs to the Leptostemonum Clade (the “spiny” Solanums) of the species-rich genus Solanum (Solanaceae). Unlike most of the genus, the eggplant and its relatives are from the Old World; most eggplant wild relatives are from Africa. An informal system for naming eggplant wild relatives largely based on crossing and other biosystematics data has been in use for approximately a decade. This system recognises several forms of two broadly conceived species, S. incanum L. and S. melongena. Recent morphological and molecular work has shown that species-level differences exist between these entities, and a new species-level nomenclature has been identified as necessary for plant breeders and for the maintenance of accurately named germplasm. Methodology/Principal Findings We examined herbarium specimens from throughout the wild species ranges as part of a larger revision of the spiny Solanums of Africa. Based on these morphological and molecular studies, we delimited species in the group to which the common eggplant belongs and constructed identification keys for the group. We also examined the monophyly of the group considered as the eggplant relatives by previous authors. Conclusions/Significance We recognise ten species in this group: S. aureitomentosum Bitter, S. campylacanthum A.Rich., S. cerasiferum Dunal, S. incanum L., S. insanum L., S. lichtensteinii Willd., S. linnaeanum Hepper & P.-M.L.Jaeger, S. melongena L., S. rigidum Lam. and S. umtuma Voronts. & S.Knapp. We review the history of naming and provide keys and character lists for all species. Ploidy level differences have not been investigated in the eggplant wild relatives; we identify this as a priority for improvement of crop wild relative use in breeding. The application of species-level names to these entities will help focus new collecting efforts for brinjal eggplant improvement and help facilitate information exchange.