Limits...
Biogeography of the Phalaenopsis amabilis species complex inferred from nuclear and plastid DNAs.

Tsai CC, Chou CH, Wang HV, Ko YZ, Chiang TY, Chiang YC - BMC Plant Biol. (2015)

Bottom Line: Demographic growth associated with the climatic oscillations in the Würm glacial period followed the species splits.Nevertheless, a subsequent population slowdown occurred in the late LGM due to extinction of regional populations.The reduction of suitable habitats resulted in geographic fragmenttation of the remaining taxa.

View Article: PubMed Central - PubMed

Affiliation: Crop Improvement Division, Kaohsiung District Agricultural Improvement Station, Pingtung, 900, Taiwan. tsaicc@mail.kdais.gov.tw.

ABSTRACT

Background: Phalaenopsis is one of the important commercial orchids in the world. Members of the P. amabilis species complex represent invaluable germplasm for the breeding program. However, the phylogeny of the P. amabilis species complex is still uncertain. The Phalaenopsis amabilis species complex (Orchidaceae) consists of subspecies amabilis, moluccana, and rosenstromii of P. amabilis, as well as P. aphrodite ssp. aphrodite, P. ap. ssp. formosana, and P. sanderiana. The aims of this study were to reconstruct the phylogeny and biogeographcial patterns of the species complex using Neighbor Joining (NJ), Maxinum Parsimony (MP), Bayesian Evolutionary Analysis Sampling Trees (BEAST) and Reconstruct Ancestral State in Phylogenies (RASP) analyses based on sequences of internal transcribed spacers 1 and 2 from the nuclear ribosomal DNA and the trnH-psbA spacer from the plastid DNA.

Results: A pattern of vicariance, dispersal, and vicariance + dispersal among disjunctly distributed taxa was uncovered based on RASP analysis. Although two subspecies of P. aphrodite could not be differentiated from each other in dispersal state, they were distinct from P. amabilis and P. sanderiana. Within P. amabilis, three subspecies were separated phylogenetically, in agreement with the vicariance or vicariance + dispersal scenario, with geographic subdivision along Huxley's, Wallace's and Lydekker's Lines. Molecular dating revealed such subdivisions among taxa of P. amabilis complex dating back to the late Pleistocene. Population-dynamic analyses using a Bayesian skyline plot suggested that the species complex experienced an in situ range expansion and population concentration during the late Last Glacial Maximum (LGM).

Conclusions: Taxa of the P. amabilis complex with disjunct distributions were differentiated due to vicariance or vicariance + dispersal, with events likely occurring in the late Pleistocene. Demographic growth associated with the climatic oscillations in the Würm glacial period followed the species splits. Nevertheless, a subsequent population slowdown occurred in the late LGM due to extinction of regional populations. The reduction of suitable habitats resulted in geographic fragmenttation of the remaining taxa.

No MeSH data available.


Geographical distribution of six species/subspecies of the Phalaenopsis amabilis species complex and Southeast Asia landmasses between the Pleistocene and the present. In Pleistocene times, Indochina, Malaya, Sumatra, Java, Borneo, and the Philippines were interconnected and were separated from Sulawesi by the Makassar Strait. Four phylogeographic break lines were shown in red dashed lines (modified from [6]) and distribution region of six species/subspecies of the Phalaenopsis amabilis species complex drawed by different color in the map. Images for six species/subspecies of the Phalaenopsis amabilis species complex were photographed by CC Tsai (the first author)
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License 1 - License 2
getmorefigures.php?uid=PMC4537552&req=5

Fig1: Geographical distribution of six species/subspecies of the Phalaenopsis amabilis species complex and Southeast Asia landmasses between the Pleistocene and the present. In Pleistocene times, Indochina, Malaya, Sumatra, Java, Borneo, and the Philippines were interconnected and were separated from Sulawesi by the Makassar Strait. Four phylogeographic break lines were shown in red dashed lines (modified from [6]) and distribution region of six species/subspecies of the Phalaenopsis amabilis species complex drawed by different color in the map. Images for six species/subspecies of the Phalaenopsis amabilis species complex were photographed by CC Tsai (the first author)

Mentions: According to the historical geology of Southeast Asia, most Philippine islands are relatively young, originating about five million years ago (Mya) [1, 2]. The older islands of the Philippines, including Palawan, Mindoro and Zamboanga, are located on the edges of the Eurasian Plate and may have been moving away from the main landmass since the early Miocene (approximately 30 Mya). Until approximately 5–10 Mya, the crust of the older plate was a part of Borneo [3–5]. The Malay Peninsula, Borneo, Sumatra and Java together comprise the Sunda Shelf. When sea levels were low during the glacial maxima, the Malay Peninsula, Borneo, Sumatra, Java, Bali and the Philippines were interconnected via land bridges, making species migrations possible [6]. In addition, western Sulawesi had been a part of the Sunda Shelf in ancient times but slid away during the Palaeocene (approximately 50 Mya). The formation of the deep Makassar Strait divided western Sulawesi from the Sunda Shelf, preventing further dispersal of Bornean species to Sulawesi. This history geology accounts for the high degree of endemism among the fauna and flora of Sulawesi [7] (Fig. 1).Fig. 1


Biogeography of the Phalaenopsis amabilis species complex inferred from nuclear and plastid DNAs.

Tsai CC, Chou CH, Wang HV, Ko YZ, Chiang TY, Chiang YC - BMC Plant Biol. (2015)

Geographical distribution of six species/subspecies of the Phalaenopsis amabilis species complex and Southeast Asia landmasses between the Pleistocene and the present. In Pleistocene times, Indochina, Malaya, Sumatra, Java, Borneo, and the Philippines were interconnected and were separated from Sulawesi by the Makassar Strait. Four phylogeographic break lines were shown in red dashed lines (modified from [6]) and distribution region of six species/subspecies of the Phalaenopsis amabilis species complex drawed by different color in the map. Images for six species/subspecies of the Phalaenopsis amabilis species complex were photographed by CC Tsai (the first author)
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4537552&req=5

Fig1: Geographical distribution of six species/subspecies of the Phalaenopsis amabilis species complex and Southeast Asia landmasses between the Pleistocene and the present. In Pleistocene times, Indochina, Malaya, Sumatra, Java, Borneo, and the Philippines were interconnected and were separated from Sulawesi by the Makassar Strait. Four phylogeographic break lines were shown in red dashed lines (modified from [6]) and distribution region of six species/subspecies of the Phalaenopsis amabilis species complex drawed by different color in the map. Images for six species/subspecies of the Phalaenopsis amabilis species complex were photographed by CC Tsai (the first author)
Mentions: According to the historical geology of Southeast Asia, most Philippine islands are relatively young, originating about five million years ago (Mya) [1, 2]. The older islands of the Philippines, including Palawan, Mindoro and Zamboanga, are located on the edges of the Eurasian Plate and may have been moving away from the main landmass since the early Miocene (approximately 30 Mya). Until approximately 5–10 Mya, the crust of the older plate was a part of Borneo [3–5]. The Malay Peninsula, Borneo, Sumatra and Java together comprise the Sunda Shelf. When sea levels were low during the glacial maxima, the Malay Peninsula, Borneo, Sumatra, Java, Bali and the Philippines were interconnected via land bridges, making species migrations possible [6]. In addition, western Sulawesi had been a part of the Sunda Shelf in ancient times but slid away during the Palaeocene (approximately 50 Mya). The formation of the deep Makassar Strait divided western Sulawesi from the Sunda Shelf, preventing further dispersal of Bornean species to Sulawesi. This history geology accounts for the high degree of endemism among the fauna and flora of Sulawesi [7] (Fig. 1).Fig. 1

Bottom Line: Demographic growth associated with the climatic oscillations in the Würm glacial period followed the species splits.Nevertheless, a subsequent population slowdown occurred in the late LGM due to extinction of regional populations.The reduction of suitable habitats resulted in geographic fragmenttation of the remaining taxa.

View Article: PubMed Central - PubMed

Affiliation: Crop Improvement Division, Kaohsiung District Agricultural Improvement Station, Pingtung, 900, Taiwan. tsaicc@mail.kdais.gov.tw.

ABSTRACT

Background: Phalaenopsis is one of the important commercial orchids in the world. Members of the P. amabilis species complex represent invaluable germplasm for the breeding program. However, the phylogeny of the P. amabilis species complex is still uncertain. The Phalaenopsis amabilis species complex (Orchidaceae) consists of subspecies amabilis, moluccana, and rosenstromii of P. amabilis, as well as P. aphrodite ssp. aphrodite, P. ap. ssp. formosana, and P. sanderiana. The aims of this study were to reconstruct the phylogeny and biogeographcial patterns of the species complex using Neighbor Joining (NJ), Maxinum Parsimony (MP), Bayesian Evolutionary Analysis Sampling Trees (BEAST) and Reconstruct Ancestral State in Phylogenies (RASP) analyses based on sequences of internal transcribed spacers 1 and 2 from the nuclear ribosomal DNA and the trnH-psbA spacer from the plastid DNA.

Results: A pattern of vicariance, dispersal, and vicariance + dispersal among disjunctly distributed taxa was uncovered based on RASP analysis. Although two subspecies of P. aphrodite could not be differentiated from each other in dispersal state, they were distinct from P. amabilis and P. sanderiana. Within P. amabilis, three subspecies were separated phylogenetically, in agreement with the vicariance or vicariance + dispersal scenario, with geographic subdivision along Huxley's, Wallace's and Lydekker's Lines. Molecular dating revealed such subdivisions among taxa of P. amabilis complex dating back to the late Pleistocene. Population-dynamic analyses using a Bayesian skyline plot suggested that the species complex experienced an in situ range expansion and population concentration during the late Last Glacial Maximum (LGM).

Conclusions: Taxa of the P. amabilis complex with disjunct distributions were differentiated due to vicariance or vicariance + dispersal, with events likely occurring in the late Pleistocene. Demographic growth associated with the climatic oscillations in the Würm glacial period followed the species splits. Nevertheless, a subsequent population slowdown occurred in the late LGM due to extinction of regional populations. The reduction of suitable habitats resulted in geographic fragmenttation of the remaining taxa.

No MeSH data available.