The Experts below are selected from a list of 315 Experts worldwide ranked by ideXlab platform
Susanne S Renner - One of the best experts on this subject based on the ideXlab platform.
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Phylogenetics of Cucumis (Cucurbitaceae) as understood in 2008 1
2020Co-Authors: Susanne S Renner, Hanno Schaefer, M. PitratAbstract:saw the publication of two molecular phylogenies of Cucumis that relied on combined chloroplast and nuclear gene regions, a nd broad species sampling. One of these studies also addressed the position of Cucumis in the Cucurbitaceae family tree. It was found that the genera Cucumella , Dicaelospermum , Mukia , Myrmecosicyos , and Oreosyce are embedded within Cucumis and that the closest relative of Cucumis is Muellerargia , a genus with one species in Australia and Indonesia, the other in Madagascar. Cucumber and its sister species, C. hystrix , are nested among Australian, Malesian, and Western Indian species that had traditionally been placed in Mukia or Dicaelospermum . Cucumis melo is sister to this Australian/Asian clade, rather than being close to African species as previously thought. Molecular clock dating suggests Eocene ages for the deepest divergences within Cucumis .
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Phylogenetics of Cucumis (Cucurbitaceae)
BMC Evolutionary Biology, 2020Co-Authors: Susanne S Renner, Hanno Schaefer, Alexander KocyanAbstract:Background: Melon, Cucumis melo, and cucumber, C. sativus, are among the most widely cultivated crops worldwide. Cucumis, as traditionally conceived, is geographically centered in Africa, with C. sativus and C. hystrix thought to be the only Cucumis species in Asia. This taxonomy forms the basis for all ongoing Cucumis breeding and genomics efforts. We tested relationships among Cucumis and related genera based on DNA sequences from chloroplast gene, intron, and spacer regions (rbcL, matK, rpl20-rps12, trnL, and trnL-F), adding nuclear internal transcribed spacer sequences to resolve relationships within Cucumis. Results: Analyses of combined chloroplast sequences (4,375 aligned nucleotides) for 123 of the 130 genera of Cucurbitaceae indicate that the genera Cucumella, Dicaelospermum, Mukia, Myrmecosicyos, and Oreosyce are embedded within Cucumis. Phylogenetic trees from nuclear sequences for these taxa are congruent, and the combined data yield a well-supported phylogeny. The nesting of the five genera in Cucumis greatly changes the natural geographic range of the genus, extending it throughout the Malesian region and into Australia. The closest relative of Cucumis is Muellerargia, with one species in Australia and Indonesia, the other in Madagascar. Cucumber and its sister species, C. hystrix, are nested among Australian, Malaysian, and Western Indian species placed in Mukia or Dicaelospermum and in one case not yet formally described. Cucumis melo is sister to this Australian/Asian clade, rather than being close to African species as previously thought. Molecular clocks indicate that the deepest divergences in Cucumis, including the split between C. melo and its Australian/Asian sister clade, go back to the mid-Eocene. Conclusion: Based on congruent nuclear and chloroplast phylogenies we conclude that Cucumis comprises an old Australian/Asian component that was heretofore unsuspected. Cucumis sativus evolved within this Australian/Asian clade and is phylogenetically far more distant from C. melo than implied by the current morphological classification.
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cucumber Cucumis sativus and melon c melo have numerous wild relatives in asia and australia and the sister species of melon is from australia
Proceedings of the National Academy of Sciences of the United States of America, 2010Co-Authors: Patrizia Sebastian, Hanno Schaefer, Ian R H Telford, Susanne S RennerAbstract:Among the fundamental questions regarding cultivated plants is their geographic origin and region of domestication. The genus Cucumis, which includes cucumber (Cucumis sativus) and melon (Cucumis melo), has numerous wild African species, and it has therefore been assumed that melon originated in Africa. For cucumber, this seemed less likely because wild cucumbers exist in India and a closely related species lives in the Eastern Himalayas. Using DNA sequences from plastid and nuclear markers for some 100 Cucumis accessions from Africa, Australia, and Asia, we show here that melon and cucumber are of Asian origin and have numerous previously overlooked species-level relatives in Australia and around the Indian Ocean. The wild progenitor of C. melo occurs in India, and our data confirm that the Southeast Asian Cucumis hystrix is the closest relative of cucumber. Most surprisingly, the closest relative of melon is Cucumis picrocarpus from Australia. C. melo diverged from this Australian sister species approximately 3 Ma, and both diverged from the remaining Asian/Australian species approximately 10 Ma. The Asian/Australian Cucumis clade comprises at least 25 species, nine of them new to science, and diverged from its African relatives in the Miocene, approximately 12 Ma. Range reconstruction under maximum likelihood suggests Asia as the ancestral area for the most recent common ancestor of melon and cucumber, fitting with both having progenitor populations in the Himalayan region and high genetic diversity of C. melo landraces in India and China. Future investigations of wild species related to melon and cucumber should concentrate on Asia and Australia.
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phylogenetics of Cucumis cucurbitaceae cucumber c sativus belongs in an asian australian clade far from melon c melo
BMC Evolutionary Biology, 2007Co-Authors: Susanne S Renner, Hanno Schaefer, Alexander KocyanAbstract:Melon, Cucumis melo, and cucumber, C. sativus, are among the most widely cultivated crops worldwide. Cucumis, as traditionally conceived, is geographically centered in Africa, with C. sativus and C. hystrix thought to be the only Cucumis species in Asia. This taxonomy forms the basis for all ongoing Cucumis breeding and genomics efforts. We tested relationships among Cucumis and related genera based on DNA sequences from chloroplast gene, intron, and spacer regions (rbcL, matK, rpl20-rps12, trnL, and trnL-F), adding nuclear internal transcribed spacer sequences to resolve relationships within Cucumis. Analyses of combined chloroplast sequences (4,375 aligned nucleotides) for 123 of the 130 genera of Cucurbitaceae indicate that the genera Cucumella, Dicaelospermum, Mukia, Myrmecosicyos, and Oreosyce are embedded within Cucumis. Phylogenetic trees from nuclear sequences for these taxa are congruent, and the combined data yield a well-supported phylogeny. The nesting of the five genera in Cucumis greatly changes the natural geographic range of the genus, extending it throughout the Malesian region and into Australia. The closest relative of Cucumis is Muellerargia, with one species in Australia and Indonesia, the other in Madagascar. Cucumber and its sister species, C. hystrix, are nested among Australian, Malaysian, and Western Indian species placed in Mukia or Dicaelospermum and in one case not yet formally described. Cucumis melo is sister to this Australian/Asian clade, rather than being close to African species as previously thought. Molecular clocks indicate that the deepest divergences in Cucumis, including the split between C. melo and its Australian/Asian sister clade, go back to the mid-Eocene. Based on congruent nuclear and chloroplast phylogenies we conclude that Cucumis comprises an old Australian/Asian component that was heretofore unsuspected. Cucumis sativus evolved within this Australian/Asian clade and is phylogenetically far more distant from C. melo than implied by the current morphological classification.
Monique D. Reed - One of the best experts on this subject based on the ideXlab platform.
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Cucumis metuliferus (Cultivated) 4
2011Co-Authors: Monique D. ReedAbstract:Cucumis metuliferus, cross-section, close. Family Cucurbitaceae, Subclass Dilleniidae. Origin: Cultivated.
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Cucumis melo subsp. melo var.cantalupensis (Cultivated)
2011Co-Authors: Monique D. ReedAbstract:Cucumis melo subsp. melo var.cantalupensis, fruit. Family Cucurbitaceae, Subclass Dilleniidae. Origin: Cultivated.
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Cucumis melo subsp. melo var. inodorus (Cultivated)
2011Co-Authors: Monique D. ReedAbstract:Cucumis melo subsp. melo var. inodorus, fruit. Family Cucurbitaceae, Subclass Dilleniidae. Origin: Cultivated.
Hanno Schaefer - One of the best experts on this subject based on the ideXlab platform.
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Phylogenetics of Cucumis (Cucurbitaceae) as understood in 2008 1
2020Co-Authors: Susanne S Renner, Hanno Schaefer, M. PitratAbstract:saw the publication of two molecular phylogenies of Cucumis that relied on combined chloroplast and nuclear gene regions, a nd broad species sampling. One of these studies also addressed the position of Cucumis in the Cucurbitaceae family tree. It was found that the genera Cucumella , Dicaelospermum , Mukia , Myrmecosicyos , and Oreosyce are embedded within Cucumis and that the closest relative of Cucumis is Muellerargia , a genus with one species in Australia and Indonesia, the other in Madagascar. Cucumber and its sister species, C. hystrix , are nested among Australian, Malesian, and Western Indian species that had traditionally been placed in Mukia or Dicaelospermum . Cucumis melo is sister to this Australian/Asian clade, rather than being close to African species as previously thought. Molecular clock dating suggests Eocene ages for the deepest divergences within Cucumis .
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Phylogenetics of Cucumis (Cucurbitaceae)
BMC Evolutionary Biology, 2020Co-Authors: Susanne S Renner, Hanno Schaefer, Alexander KocyanAbstract:Background: Melon, Cucumis melo, and cucumber, C. sativus, are among the most widely cultivated crops worldwide. Cucumis, as traditionally conceived, is geographically centered in Africa, with C. sativus and C. hystrix thought to be the only Cucumis species in Asia. This taxonomy forms the basis for all ongoing Cucumis breeding and genomics efforts. We tested relationships among Cucumis and related genera based on DNA sequences from chloroplast gene, intron, and spacer regions (rbcL, matK, rpl20-rps12, trnL, and trnL-F), adding nuclear internal transcribed spacer sequences to resolve relationships within Cucumis. Results: Analyses of combined chloroplast sequences (4,375 aligned nucleotides) for 123 of the 130 genera of Cucurbitaceae indicate that the genera Cucumella, Dicaelospermum, Mukia, Myrmecosicyos, and Oreosyce are embedded within Cucumis. Phylogenetic trees from nuclear sequences for these taxa are congruent, and the combined data yield a well-supported phylogeny. The nesting of the five genera in Cucumis greatly changes the natural geographic range of the genus, extending it throughout the Malesian region and into Australia. The closest relative of Cucumis is Muellerargia, with one species in Australia and Indonesia, the other in Madagascar. Cucumber and its sister species, C. hystrix, are nested among Australian, Malaysian, and Western Indian species placed in Mukia or Dicaelospermum and in one case not yet formally described. Cucumis melo is sister to this Australian/Asian clade, rather than being close to African species as previously thought. Molecular clocks indicate that the deepest divergences in Cucumis, including the split between C. melo and its Australian/Asian sister clade, go back to the mid-Eocene. Conclusion: Based on congruent nuclear and chloroplast phylogenies we conclude that Cucumis comprises an old Australian/Asian component that was heretofore unsuspected. Cucumis sativus evolved within this Australian/Asian clade and is phylogenetically far more distant from C. melo than implied by the current morphological classification.
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cucumber Cucumis sativus and melon c melo have numerous wild relatives in asia and australia and the sister species of melon is from australia
Proceedings of the National Academy of Sciences of the United States of America, 2010Co-Authors: Patrizia Sebastian, Hanno Schaefer, Ian R H Telford, Susanne S RennerAbstract:Among the fundamental questions regarding cultivated plants is their geographic origin and region of domestication. The genus Cucumis, which includes cucumber (Cucumis sativus) and melon (Cucumis melo), has numerous wild African species, and it has therefore been assumed that melon originated in Africa. For cucumber, this seemed less likely because wild cucumbers exist in India and a closely related species lives in the Eastern Himalayas. Using DNA sequences from plastid and nuclear markers for some 100 Cucumis accessions from Africa, Australia, and Asia, we show here that melon and cucumber are of Asian origin and have numerous previously overlooked species-level relatives in Australia and around the Indian Ocean. The wild progenitor of C. melo occurs in India, and our data confirm that the Southeast Asian Cucumis hystrix is the closest relative of cucumber. Most surprisingly, the closest relative of melon is Cucumis picrocarpus from Australia. C. melo diverged from this Australian sister species approximately 3 Ma, and both diverged from the remaining Asian/Australian species approximately 10 Ma. The Asian/Australian Cucumis clade comprises at least 25 species, nine of them new to science, and diverged from its African relatives in the Miocene, approximately 12 Ma. Range reconstruction under maximum likelihood suggests Asia as the ancestral area for the most recent common ancestor of melon and cucumber, fitting with both having progenitor populations in the Himalayan region and high genetic diversity of C. melo landraces in India and China. Future investigations of wild species related to melon and cucumber should concentrate on Asia and Australia.
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phylogenetics of Cucumis cucurbitaceae cucumber c sativus belongs in an asian australian clade far from melon c melo
BMC Evolutionary Biology, 2007Co-Authors: Susanne S Renner, Hanno Schaefer, Alexander KocyanAbstract:Melon, Cucumis melo, and cucumber, C. sativus, are among the most widely cultivated crops worldwide. Cucumis, as traditionally conceived, is geographically centered in Africa, with C. sativus and C. hystrix thought to be the only Cucumis species in Asia. This taxonomy forms the basis for all ongoing Cucumis breeding and genomics efforts. We tested relationships among Cucumis and related genera based on DNA sequences from chloroplast gene, intron, and spacer regions (rbcL, matK, rpl20-rps12, trnL, and trnL-F), adding nuclear internal transcribed spacer sequences to resolve relationships within Cucumis. Analyses of combined chloroplast sequences (4,375 aligned nucleotides) for 123 of the 130 genera of Cucurbitaceae indicate that the genera Cucumella, Dicaelospermum, Mukia, Myrmecosicyos, and Oreosyce are embedded within Cucumis. Phylogenetic trees from nuclear sequences for these taxa are congruent, and the combined data yield a well-supported phylogeny. The nesting of the five genera in Cucumis greatly changes the natural geographic range of the genus, extending it throughout the Malesian region and into Australia. The closest relative of Cucumis is Muellerargia, with one species in Australia and Indonesia, the other in Madagascar. Cucumber and its sister species, C. hystrix, are nested among Australian, Malaysian, and Western Indian species placed in Mukia or Dicaelospermum and in one case not yet formally described. Cucumis melo is sister to this Australian/Asian clade, rather than being close to African species as previously thought. Molecular clocks indicate that the deepest divergences in Cucumis, including the split between C. melo and its Australian/Asian sister clade, go back to the mid-Eocene. Based on congruent nuclear and chloroplast phylogenies we conclude that Cucumis comprises an old Australian/Asian component that was heretofore unsuspected. Cucumis sativus evolved within this Australian/Asian clade and is phylogenetically far more distant from C. melo than implied by the current morphological classification.
Ales Lebeda - One of the best experts on this subject based on the ideXlab platform.
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Embryo rescue of cucumber ( Cucumis sativus ), muskmelon ( C. melo ) and some wild Cucumis species ( C. anguria, C. zeyheri , and C. metuliferus )
Journal of applied botany and food quality, 2012Co-Authors: D. Skálová, B. Navrátilová, Ales LebedaAbstract:Cucumis sativus is one of the most economically important crops of the Cucurbitaceae. Recent cucumber cultivars are susceptible to some serious diseases and pests, including downy mildew, powdery mildew, nematodes, and spider mites. Sources of resistance to these pathogens and pests were identified in some accessions of wild Cucumis species. One possible way of introducing these resistances into cucumber germplasm is interspecific hybridization. However, C. sativus is sexually incompatible with nearly all other Cucumis species, because of substantially different chromosome numbers, n = 7 in C. sativus versus n = 12 in C. melo and most wild Cucumis species. Overcoming this obstacle can be accomplished through the use of embryo rescue and/or ovule culture. Results of experiments using these methods, especially of embryo rescue of cucumber and selected wild Cucumis species after intra- and interspecific hybridization, are summarized in this paper. Various culture media and selected genotypes were tested in our experiments. Successful regeneration of mature embryos of some Cucumis spp. was observed on all types of media, and callus or sporadic plant formation from immature embryos and seeds occurred on media with coconut water and gibberellic acid.
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Biotechnological methods utilized in Cucumis research - A review
Horticultural Science, 2011Co-Authors: B. Navrátilová, D. Skálová, V. Ondřej, Miloslav Kitner, Ales LebedaAbstract:NAVRATILOVA B., SKALOVA D., ONDIZEJ V., KITNER M., LEBEDA A., 2011. Biotechnological methods utilized in Cucumis research -A review. Hort. Sci. (Prague), 38: 150-158. Our biotechnological research on selected Cucumis species has encompassed interspecific hybridization via embryo-rescue, in vitro pollination, somatic hybridization and cytogenetics of protoplasts. Embryo-rescue and in vitro pollina-tion are suitable in vitro techniques for production of hybrid embryos. These methods were tested and optimized for cucurbits. Protoplast culture is another valuable tool for biotechnological applications, such as somatic hybridization and genetic transformation. We study protoplast dedifferentiation not only as a biotechnological application in breeding systems, but mainly to describe mechanisms of obtaining totipotency. Protoplasts of cucurbits were studied cytogeneti-cally to observe changes in nuclear architecture during protoplastization and regeneration and for comparison with the expression profile obtained using cDNA-AFLP techniques and reverse transcription for the specific genes involved.
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Polyploidization Facilitates Biotechnological In Vitro Techniques in the Genus Cucumis
BioMed Research International, 2010Co-Authors: D. Skálová, B. Navrátilová, Vladan Ondřej, Ivana Doležalová, Ales LebedaAbstract:Prezygotic interspecific crossability barrier in the genus Cucumis is related to the ploidy level of the species (cucumber (C. sativus), x = 7; muskmelon (C. melo) and wild Cucumis species, x = 12). Polyploidization of maternal plants helps hybridization among other Cucumis species by overcoming prezygotic genetic barriers. The main objective of this paper is to compare the results of several methods supporting interspecific crosses in cucumber without and with polyploidization (comparison between diploid (2x) and mixoploid (2x/4x) cucumber maternal plants). Mixoploid plants were obtained after in vivo and in vitro polyploidization by colchicine and oryzalin. Ploidy level was estimated by flow cytometry. Embryo rescue, in vitro pollination, and isolation of mesophyll protoplast were tested and compared. Positive effect of polyploidization was observed during all experiments presented by higher regeneration capacity of cultivated mixoploid cucumber embryos, ovules, and protoplasts. Nevertheless, the hybrid character of putative hybrid accessions obtained after cross in vivo and in vitro pollination was not confirmed.
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Factors affecting protoplast isolation and cultivation of Cucumis spp.
Journal of Applied Botany and Food Quality, 2007Co-Authors: J. Gajdová, B. Navrátilová, J. Smolná, Ales LebedaAbstract:Protoplasts of Cuciunis anguria, Cucumis inelo (3 accessions), Cucumis metuliferus and Cucumis sativus were isolated from leaves, growling apices, hypocotyls and calluses. plants were cultured(l Oil 2 concentrations of sucrose. The effect of plant Culture medium, explant age and explant type oil protoplast viability were investigated. The protoplasts were Cultured in 3 types Of Culture medium and at two temperatures. Optimal age range for protoplast isolation was 1-5 weeks depending oil explant type and genotype. Viabilities ranging between 50 % and 80 % were obtained from all explants and genotypes. Increased concentration Of Sucrose had negative impact oil viability of protoplasts. The highest level of regeneration achieved was callus, regenerated frorn leaf protoplasts of C. melo cv. 'Charentais' and C. melo 'MR-1'. The lowest regeneration capability was observed in hypocotyls. Liquid LCM medium (B5 macro and microelements (Ig . 1(-1) CaCl2), B5 vitamins with 1g 1(-1) myo-inositol, 2 mg .1(-1) ascorbic acid. 0.8 mg.1(-1) glycine, 20 mg.l(-1) glutamine, 100 mg. l(-1) casein hydrolysate, 70g . l(-1) mannitol, 10g .l(-1) sucrose, 5g l(-1) glucose, 585 mg . l(-1) NIES, 5.37 mu mol . l(-1) NAA, 2.26 mu mol . l(-1) 2,4-D, 2.22 mu mol . l(-1) BA) was optimal for protoplast regeneration. Agarose-solidified medium caused a decrease in the number of cell divisions (Used ill C. melo 'PI 124 112 degrees). Cultivation at 25 degrees C resulted in a higher frequency of cell divisions (tested in C. metuliferus).
Alexander Kocyan - One of the best experts on this subject based on the ideXlab platform.
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Phylogenetics of Cucumis (Cucurbitaceae)
BMC Evolutionary Biology, 2020Co-Authors: Susanne S Renner, Hanno Schaefer, Alexander KocyanAbstract:Background: Melon, Cucumis melo, and cucumber, C. sativus, are among the most widely cultivated crops worldwide. Cucumis, as traditionally conceived, is geographically centered in Africa, with C. sativus and C. hystrix thought to be the only Cucumis species in Asia. This taxonomy forms the basis for all ongoing Cucumis breeding and genomics efforts. We tested relationships among Cucumis and related genera based on DNA sequences from chloroplast gene, intron, and spacer regions (rbcL, matK, rpl20-rps12, trnL, and trnL-F), adding nuclear internal transcribed spacer sequences to resolve relationships within Cucumis. Results: Analyses of combined chloroplast sequences (4,375 aligned nucleotides) for 123 of the 130 genera of Cucurbitaceae indicate that the genera Cucumella, Dicaelospermum, Mukia, Myrmecosicyos, and Oreosyce are embedded within Cucumis. Phylogenetic trees from nuclear sequences for these taxa are congruent, and the combined data yield a well-supported phylogeny. The nesting of the five genera in Cucumis greatly changes the natural geographic range of the genus, extending it throughout the Malesian region and into Australia. The closest relative of Cucumis is Muellerargia, with one species in Australia and Indonesia, the other in Madagascar. Cucumber and its sister species, C. hystrix, are nested among Australian, Malaysian, and Western Indian species placed in Mukia or Dicaelospermum and in one case not yet formally described. Cucumis melo is sister to this Australian/Asian clade, rather than being close to African species as previously thought. Molecular clocks indicate that the deepest divergences in Cucumis, including the split between C. melo and its Australian/Asian sister clade, go back to the mid-Eocene. Conclusion: Based on congruent nuclear and chloroplast phylogenies we conclude that Cucumis comprises an old Australian/Asian component that was heretofore unsuspected. Cucumis sativus evolved within this Australian/Asian clade and is phylogenetically far more distant from C. melo than implied by the current morphological classification.
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phylogenetics of Cucumis cucurbitaceae cucumber c sativus belongs in an asian australian clade far from melon c melo
BMC Evolutionary Biology, 2007Co-Authors: Susanne S Renner, Hanno Schaefer, Alexander KocyanAbstract:Melon, Cucumis melo, and cucumber, C. sativus, are among the most widely cultivated crops worldwide. Cucumis, as traditionally conceived, is geographically centered in Africa, with C. sativus and C. hystrix thought to be the only Cucumis species in Asia. This taxonomy forms the basis for all ongoing Cucumis breeding and genomics efforts. We tested relationships among Cucumis and related genera based on DNA sequences from chloroplast gene, intron, and spacer regions (rbcL, matK, rpl20-rps12, trnL, and trnL-F), adding nuclear internal transcribed spacer sequences to resolve relationships within Cucumis. Analyses of combined chloroplast sequences (4,375 aligned nucleotides) for 123 of the 130 genera of Cucurbitaceae indicate that the genera Cucumella, Dicaelospermum, Mukia, Myrmecosicyos, and Oreosyce are embedded within Cucumis. Phylogenetic trees from nuclear sequences for these taxa are congruent, and the combined data yield a well-supported phylogeny. The nesting of the five genera in Cucumis greatly changes the natural geographic range of the genus, extending it throughout the Malesian region and into Australia. The closest relative of Cucumis is Muellerargia, with one species in Australia and Indonesia, the other in Madagascar. Cucumber and its sister species, C. hystrix, are nested among Australian, Malaysian, and Western Indian species placed in Mukia or Dicaelospermum and in one case not yet formally described. Cucumis melo is sister to this Australian/Asian clade, rather than being close to African species as previously thought. Molecular clocks indicate that the deepest divergences in Cucumis, including the split between C. melo and its Australian/Asian sister clade, go back to the mid-Eocene. Based on congruent nuclear and chloroplast phylogenies we conclude that Cucumis comprises an old Australian/Asian component that was heretofore unsuspected. Cucumis sativus evolved within this Australian/Asian clade and is phylogenetically far more distant from C. melo than implied by the current morphological classification.
