Gang Uk Suh

Bio: Gang Uk Suh is an academic researcher from Korea Forest Service. The author has contributed to research in topics: Germination & Seedling. The author has an hindex of 7, co-authored 17 publications receiving 99 citations.

The Korean Baekdudaegan Mountains: A Glacial Refugium and a Biodiversity Hotspot That Needs to Be Conserved

Abstract: This research was supported by Korea Research Foundation grants; KRF-2013R1A1A2063524 to MYC and NRF-2011-0017236, NRF-2013R1A1A3010892, and NRF-2017R1A2B4012215 to MGC and was carried out as part of the Infrastructure for the Conservation and Restoration of Rare and Endemic Plants in Korea National Arboretum that supported to MGC from 2015 to 2018.

Improvement of asymbiotic seed germination and seedling development of Cypripedium macranthos Sw. with organic additives

Abstract: To find the optimal propagation condition for endangered Cypripedium macranthos Sw., also known as lady's slipper orchid, the effect of various organic additives on in vitro germination, protocorm formation and seedling growth was investigated during asymbiotic seed culture. When 100 ml·L -1 coconut water was added to the basal medium, the highest germination rate and protocorm formation rate were achieved, with 70.8% and 74.2% respectively. Supplementation of phloem sap from birch tree or maple tree also showed a facilitating effect to improve the germination and protocorm development. With 100 ml·L -1 birch sap or maple sap, both the germination and protocorm formation rates were roughly more than 65% and 68%. The roots and buds of the seedlings grew vigorously in the medium containing 100 ml·L -1 coconut water or phloem sap, in particular, their bud formation rates increased by more than 70%. Addition of banana powder and peptone could not create a more significantly favorable culture condition, and non-addition had the worst results. Our results demonstrated that proper organic amendments such as coconut water and phloem sap might be preferred to in vitro germination and the growth of seedlings developed from the protocorm of C. macranthos Sw. during asymbiotic seed culture.

Comparison of genetic variation between northern and southern populations of Lilium cernuum (Liliaceae): Implications for Pleistocene refugia.

Abstract: The so-called "Baekdudaegan" (BDDG), a mountain range that stretches along the Korean Peninsula, has been recently proposed as a major "southern" glacial refugium for boreal or temperate plant species based on palaeoecological and, especially, genetic data. Genetic studies comparing genetic variation between population occurring on the BDDG and more northern ones (i.e. in NE China and/or in Russian Far East) are, however, still too few to draw firm conclusions on the role of the BDDG as a refugium and a source for possible northward post-glacial recolonizations. In order to fill this gap, we selected a boreal/temperate herb, Lilium cernuum, and compared levels of allozyme-based genetic diversity of five populations from NE China with five populations from South Korea (home of its hypothesized refuge areas). As a complementary tool, we used the maximum entropy algorithm implemented in MaxEnt to infer the species' potential distribution for the present time, which was projected to different past climate scenarios for the Last Glacial Maximum (LGM). Permutation tests revealed that Korean populations harbored significantly higher levels of within-population genetic variation than those from NE China (expected heterozygosity = 0.173 vs. 0.095, respectively). Our results suggest that the lowered levels of genetic diversity in NE Chinese populations might be due to founder effects associated with post-glacial migration from southern regions. Congruent with genetic data, past distribution models showed higher probability of occurrence in southern ranges than in northern ones during the LGM. In addition, a positive correlation was detected between the expected heterozygosity and environmental LGM suitability. From a conservation perspective, our results further suggest that the southern populations in South Korea may be particularly worthy of protection.

Embryo, Seed coat and Pericarp Development in Abeliophyllum distichum Nakai (Oleaceae)

Abstract: Abeliophyllum distichum is a monotypic taxon of Oleaceae and endemic to Korea. A comprehensive study on embryogeny and fruit and seed coat ontogeny in Abeliophyllum was carried out via microtome and light microscopy. The fertilization occurs during mid? to late April and embryo matures by early July. The embryo development follows the general fashion from globular embryo ? transition embryo ? heart shaped embryo ? torpedo embryo ? walking-stick embryo to mature embryo. The pericarp clearly differentiates into three histological zones: exocarp, mesocarp, and endocarp. The young seed comprises 10-12 cells thick seed coat and the mature seed coat comprises an exotesta, 6-8 mesotesta and an endotesta. Any crystals, phenolic-like compounds, idioblasts, and the sclereids are not found in pericarp as well as seed coat. An overall development confirms Solanade type of embryogenesis in Abeliophyllum. The endocarp becomes more prominent in mature fruit and all the layers of endocarp are highly lignified. On the basis of mechanical layer the seed coat is of exotestal type.

Physiological Plant Ecology Ecophysiology And Stress Physiology Of Functional Groups

Abstract: Excellent book is always being the best friend for spending little time in your office, night time, bus, and everywhere. It will be a good way to just look, open, and read the book while in that time. As known, experience and skill don't always come with the much money to acquire them. Reading this book with the PDF physiological plant ecology ecophysiology and stress physiology of function groups will let you know more things.

Phylogeny and classification of Oleaceae based on rps16 and trnL-F sequence data

Abstract: Phylogenetic relationships among 76 species of Oleaceae, representing all 25 recognized genera of the family, were assessed by a cladistic analysis of DNA sequences from two noncoding chloroplast loci, the rps16 intron and the trnL-F region. Consensus trees from separate and combined analyses are congruent and agree well with nonmolecular data (chromosome numbers, fruit and wood anatomy, leaf glycosides, and iridoids). The two debated genera Dimetra and Nyctanthes, previously suggested to belong to Verbenaceae (sensu lato) or Nyctanthaceae, are shown to belong to Oleaceae, sister to the hitherto genus incertae sedis Myxopyrum. This clade is also supported by anatomical and chemical data. The subfamily Jasminoideae is paraphyletic, and a new classification is presented. The subfamily level is abandoned, and the former Jasminoideae is split into four tribes: Myxopyreae (Myxopyrum, Nyctanthes, and Dimetra), Fontanesieae (Fontanesia), Forsythieae (Abeliophyllum and Forsythia), and Jasmineae (Jasminum and Menodora). The tribe Oleeae (previous subfamily Oleoideae) is clearly monophyletic, comprising the subtribes Ligustrinae (Syringa and Ligustrum), Schreberinae status novus (Schrebera and Comoranthus), Fraxininae status novus (Fraxinus), and Oleinae (12 drupaceous genera). An rps16 sequence obtained from Hesperelaea, known only from the type specimen collected in 1875, confirmed the placement of this extinct taxon in the subtribe Oleinae.

Identifying long-term stable refugia for relict plant species in East Asia

Abstract: Today East Asia harbors many "relict" plant species whose ranges were much larger during the Paleogene-Neogene and earlier. The ecological and climatic conditions suitable for these relict species have not been identified. Here, we map the abundance and distribution patterns of relict species, showing high abundance in the humid subtropical/warm-temperate forest regions. We further use Ecological Niche Modeling to show that these patterns align with maps of climate refugia, and we predict species' chances of persistence given the future climatic changes expected for East Asia. By 2070, potentially suitable areas with high richness of relict species will decrease, although the areas as a whole will probably expand. We identify areas in southwestern China and northern Vietnam as long-term climatically stable refugia likely to preserve ancient lineages, highlighting areas that could be prioritized for conservation of such species.

Modeling the Brain

Abstract: Human beings have always speculated about the nature of things These speculations have taken form as models Though we cannot directly know the brain, models can approximate it Therefore, neuroscience develops models of the brain Two general categories of approach to neuroscience model making are covered One is to start at the foundational units and build up from there (bottom-up) and the other is to begin by formulating a broad, general picture and then analyze down to the individual parts (top-down) Mathematics has been a helpful tool for working with the complex, multi-factored dynamic data the brain presents Typically, in the Western social sciences, and especially in psychotherapy, verbal models are used to explain human individual, interpersonal, and group behavior More recently, science has adopted sophisticated ways to model using mathematics as an alternative to verbal concepts Chapter 6 describes the prominent neuroscience modeling methods in simple, straightforward terms that anyone can understand, including Bayesian inference, Stochastic estimation, optimal control, the Markov chain, and the Bellman equation Some mathematically based models of the brain are also described such as connectionist models, tensor theories, and dynamical systems approaches As models, technologies, and statistical methods improve, neuroscience forges ever deeper into the recesses of the brain to uncover its secrets and activate the vast potentials that lie hidden, just waiting to be discovered

De Novo Transcriptome Assembly and Population Genetic Analyses for an Endangered Chinese Endemic Acer miaotaiense (Aceraceae)

Abstract: Acer miaotaiense (P. C. Tsoong) is a rare and highly endangered plant in China. Because of the lack of genomic information and the limited number of available molecular markers, there are insufficient tools to determine the genetic diversity of this species. Here, 93,305 unigenes were obtained by multiple assembled contigs with a transcriptome sequencing program. Furthermore, 12,819 expressed sequence tag-derived simple sequence repeat (EST-SSR) markers were generated, 300 were randomly selected and synthesized, 19 primer pairs were identified as highly polymorphic (average number of alleles (Na) = 8, expected heterozygosity (He) = 0.635, polymorphism information content (PIC) = 0.604) and were further used for population genetic analysis. All 261 samples were grouped into two genetic clusters by UPGMA, a principal component analyses and a STRUCTURE analyses. A moderate level of genetic differentiation (genetic differentiation index (Fst) = 0.059–0.116, gene flow = 1.904–3.993) among the populations and the major genetic variance (81.01%) within populations were revealed by the AMOVA. Based on the results, scientific conservation strategies should be established using in situ and ex situ conservation strategies. The study provides useful genetic information for the protection of precious wild resources and for further research on the origin and evolution of this endangered plant and its related species.