Dos articles de J. López-Pujol, a JoH
La prestigiosa revista nordamericana Journal of Heredity (editada per l’American Genetic Association), acaba de publicar el seu volum 104 (2) corresponent a març-abril de 2013, que conté dos articles del nostre company Jordi López-Pujol amb l’equip d’investigadors coreans sobfre diversitat genètica i refugis, amb implicacions en la biologia reproductiva i la conservació d’orquídies i falgueres d’aquest país asiàtic.
Els articles són:
M. Y. Chung, J. López-Pujol, M. Maki, M-O. Moon, J. O. Hyun & M. G. Chung (2013)
Genetic Variation and Structure within 3 Endangered Calanthe Species (Orchidaceae) from Korea: Inference of Population-Establishment History and Implications for Conservation. Journal of Heredity 104(2): 248-262 doi:10.1093/jhered/ess088
M. Y. Chung, J. López-Pujol, J. M. Chung, M-O. Moon & M. G. Chung (2013)
Genetic Diversity in the Homosporous Fern Ophioglossum vulgatum (Ophioglossaceae) from South Korea: Inference of Mating System and Population History. Journal of Heredity 104(2): 263-272 doi:10.1093/jhered/ess087
M. Y. Chung, J. López-Pujol, M. Maki, M-O. Moon, J. O. Hyun & M. G. Chung (2013)
Genetic Variation and Structure within 3 Endangered Calanthe Species (Orchidaceae) from Korea: Inference of Population-Establishment History and Implications for Conservation. Journal of Heredity 104(2): 248-262 doi:10.1093/jhered/ess088
It is thought that the warm-temperate vegetation of Korea, which at present is limited to southern coastal areas, was founded by individuals from glacial refugia putatively located in southern Japan and/or southern China. Two scenarios of postglacial recolonization can be hypothesized: 1) extant Korean populations are derived from multiple source populations or, 2) they originated from a single source. To test which of these scenarios is more likely, we surveyed patterns of genetic diversity in 3 congeneric terrestrial orchids that are typical of Korean warm-temperate vegetation, Calanthe discolor, C. sieboldii, and C. reflexa. In total, we studied 14 populations with 17 allozyme loci. To complement the study, we also tested the 2 scenarios with previous population-genetics data reported for other warm-temperate plant species native to Korea. Levels of genetic variation in the 3 Calanthe species were substantially higher than those typical of allozyme-based studies in other terrestrial orchid species, which clearly suggest a pattern of postglacial recolonization fitting the first scenario. However, previous studies with native Korean species showed equivocal patterns and suggest conflicting scenarios. The Calanthe species studied here and the previous genetic surveys conducted on other species indicate that the establishment of contemporary warm-temperate vegetation in Korea has been diverse since deglaciation. From a conservation perspective, C. reflexa should be regarded as endangered in Korea, needing special attention to preserve its current genetic diversity and to prevent further decreases in population sizes.
- Enllaç a l’article – Journal of Heredity
M. Y. Chung, J. López-Pujol, J. M. Chung, M-O. Moon & M. G. Chung (2013)
Genetic Diversity in the Homosporous Fern Ophioglossum vulgatum (Ophioglossaceae) from South Korea: Inference of Mating System and Population History. Journal of Heredity 104(2): 263-272 doi:10.1093/jhered/ess087
It is generally believed that the members of Ophioglossaceae have subterranean, potentially bisexual gametophytes, which favor intragametophytic selfing. In Ophioglossaceae, previous allozyme studies revealed substantial inbreeding within Botrychium species and Mankyua chejuense. However, little is known about the mating system in species of the genus Ophioglossum. Molecular marker analyses can provide insights into the relative occurrence of selfing versus cross-fertilization in the species of Ophioglossum. We investigated allozyme variation in 8 Korean populations of the homosporous fern Ophioglossum vulgatum to infer its mating system and to get some insight into the population-establishment history in South Korea. We detected homozygous genotypes for alternative alleles at several loci, which suggest the occurrence of intragametophytic self-fertilization. Populations harbor low within-population variation (% P = 7.2, A = 1.08, and H e = 0.026) and a high among-population differentiation (F ST = 0.733). This, together with the finding that alternative alleles were fixed at several loci, suggests that the number and size of populations of O. vulgatum might have been severely reduced during the last glaciation (i.e., due to its in situ persistence in small, isolated refugia). The combined effects of severe random genetic drift and high rates of intragametophytic selfing are likely responsible for the genetic structure displayed by this homosporous fern. Its low levels of genetic diversity in South Korea justify the implementation of some conservation measures to ensure its long-term preservation.
- Enllaç a l’article – Journal of Heredity