Wan-Geun Park

Physiological Response and Growth Performance of Parasenecio firmus under Different Shading Treatments

This study was conducted to investigate the chlorophyll contents, photosynthetic characteristics, chlorophyll fluorescence, and growth performance of Parasenecio firmus under changing light environment. Parasenecio firmus was grown under non-treated (full sunlight) and three different shading conditions (88~93%, 65~75% and 45%~55% of full sunlight) for the experiment. Total chlorophyll content, photochemical efficiency (Fv/Fm), T/R ratio, specific leaf area (SLA), leaf area ratio (LAR), and leaf weight ratio (LWR) were increased with increasing shading level, but decreased dark respiration. Therefore, light absorption and light utilization efficiency were improved under the low intensity light. Plants under 65~75% of full sunlight had best maximum photosynthetic rate and net apparent quantum yield in May. On the other hand, the non-treated plants had lower maximum photosynthetic rate, photochemical efficiency, and chlorophyll content than the treated ones. Parasenecio firmus considered to be a sciophyte, is fairly sensitive to high intensity light. If 88-93% of full sunlight lasts for a long period, photosynthetic capacity will be sharply decreased, though limiting light. These results suggest that growth of Parasenecio firmus adapted to 65~75% of full sunlight.

A Consideration of the Possibility of Planting Cryptomeria japonica and Chamaecyparis obtusa on the East Sea Area in Gangwon-Province by Tree Ring Dating and Climatic Factor Analysis

Abstract We measured radial growth of Cryptomeria japonica and Chamaecyparis obtusa growing in Gangneung, Boseong, Yangsan and Ulleung-do, respectively and analyzed its relationship with temperature and precipitation. We found from the result of tree ring counting that forest stands of Cryptomeria japonica in Gangneung and Boseong was 40 to 50 years old and 50 to 70 years old in Yangsan and Ulleung-do. According to climate change, the mean temperature in Gangneung was found to be 12 o C to 13 o C which was similar to that of Boseong and Yangsan 40 to 50 years ago. While the result of the radial growth measured from Cryptomeria japonica in Gangneung showed a slightly decreasing tendency compared to the other areas, Chamaecyparis obtusa showed an increasing tendency. In the case of Cryptomeria japonica, a strong negative correlation between radial growth and climate related variables including both mean temperature and mean precipitation existed in Ulleung. There was a strong negative correlation between radial growth and mean temperature for Chamaecyparis obtusa in Yangsan, although there was a positive correlation in Gangneung and Yangsan.Key Words: Cryptomeria japonica, Chamaecyparis obtusa, Annual diameter, Climatic Factor, Tree Ring

Genetic diversity and hybridization of Pulsatilla tongkangensis based on the nrDNA ITS region sequence

Pulsatilla tongkangensis, a perennial medicinal herb growing on the cliffs of Tongkang, Kangwon Province, Korea, is accordingly named as P. tongkangensis as a new Pulsatilla species. Due to sharing similar morphological characters with other Pulsatilla species, how to accurately discriminate P. tongkangensis becomes a critical, urgently needed-solved problem. To understand the truth of P. tongkangensis derivation and the phylogenetic relationship in Pulsatilla, the internal transcribed spacer (ITS) region of nuclear ribosomal DNA (nrDNA) as the most frequently used marker for distinguishing plant species was amplified from P. tongkangensis in this study. According to sequence alignment result, three P. tongkangensis-specific nucleotide sites were obtained to vary from other Pulsatilla species, particularly one at 417 bp showing completely homology among P. tongkangensis accessions and completely dissimilarity between P. tongkangensis and other Pulsatilla species. As known fungal contamination is common in herbal medicinal materials when improperly processed and stored, using universal primers of the ITS region could not only plant DNA but parasitic fungal DNA. Thus, to improve the amplification condition of the ITS region from P. tongkangensis and design plant-specific primer would the following focus of our study. This work will be useful for clearly understanding the phylogenetic relationship between P. tongkangensis and other species belonging to the genus Pulsatilla.

Genetic diversity of Kalopanax pictus populations in Korea based on the nrDNA ITS sequence

Kalopanax pictus is a long-lived deciduous pe- rennial tree in the family Araliaceae mainly distributed in the East Asia. In Korea, this species is of ecological and medical importance. Because typical populations of this species are small and distributed in patches, K. pictus has been considered as a narrow habitat species. To understand the genetic di- versity and population structure of this species, the sequence variation of the nuclear ribosomal DNA (nrDNA) internal transcribed spacer (ITS) region was analyzed among 18 different K. pictus populations in the present investigation. The nrDNA ITS sequences of Korean populations inves- tigated in this study showed identical of 616 bp in length, and no any nucleotide variation was found in the entire nrDNA ITS region sequence. This result suggested that the K. pictus populations in Korea might belong to the same isolate, and no mutation was found in the nrDNA ITS region. Compared with other known ITS sequence sources from K. pictus populations, only four variable nucleotide sites were found within the entire ITS region. Very narrow genetic diversity appearing in the population level of K. pictus makes us hypothesize that their relatively isolated habitats. The long-lived traits might be one main reason. However, another probability was that the nr- DNA ITS region might be noneffective in classifying po- pulations of K. pictus. Thus, to further understand the phy- logenetic relationship of K. pictus populations, more samplings should be performed based on more DNA sequences.

Phylogeny and evolution of Carpinus based on nrDNA ITS region sequences

The Coryloideae (Betulaceae) has four genera genus: Carpinus, Corylus, Ostrya, and Ostryopsis, of which Carpinus is the largest one with ∼ 35 living species, distributed in an intercontinental disjunct way in Europe, North America, and eastern Asia, particularly China. Most of the species possess great ecological and economic significance. The present study is undertaken with an aim to understand the genetic diversity among 14 main Carpinus species and focus to orientate C. turczaninovii collected from different geographical regions of Korea in the phylogenetic tree based on nuclear ribosomal DNA (nrDNA) ITS sequences. The results suggested that European Hornbeam showed 98% high similarity with Korean Hornbeam, Oriental Hornbeam, and Chinese Hornbeam, Turkzaninovs Hornbeam, Arishan Hornbeam, Yunan Hornbeam, and Aka-shide Hornbeam; Korean Hornbeam and Russian Hornbeam are nearly 100% similar; Japanese Hornbeam and Fang Hornbeam were contrarily apart from Oriental Hornbeam compared with Russian Hornbeam. Furthermore, most of species are monophyletic, except C. coreana, C. turczaninovii, C. polyneura, C. japonica, and C. caroliniana are paraphyletic. The sequence data generated in the present investigation will help for further studies in intraspecies, and their phylogenetic analysis, biogeographical, molecular evolution studies and also pave way for future phylogenetic and/or evolution studies among the other groups belongs to the family Betulaceae.

Flora of the Coastal Forests on the Same Latitude of East and West Coast in Korea

Investigation of flora was performed from March to October of 2008 as Eastern and Western coastal districts located in the same latitude (), in order to apply this to basic data for effective protection and management of coastal forests also for insurance of biodiversity in coastal forests. As a result of the investigation of floras, both coastal forests recorded product-plants as follows: 98 families, 262 genera, 370 species, 46 varieties, 4 forms, 1 hybrid, 421 taxa in total. The Eastern coastal forests had 85 families, 188 genus, 248 species, 32 varieties, 3 forms, 1 hybrid, 285 taxa in total, whereas Western coastal forest had 96 families, 227 genus, 306 species, 39 varieties, 2 forms, 1 hybrid, 348 taxa in total. Among them, seashore plants accounted for 10.2% of total plants appeared in both coastal, and they are 26 families, 38 genus, 40 species, 3 hybrids and 43 taxa in total. There are special Korea plants in both coastal; 9 families, 9 genus, 8 species, 1 varieties, 1 hybrid, 10 taxa in total. There are rare plants in both coastal; 8 families, 8 genus, 7 species, 1 varieties, 8 taxa in total. Naturalized plants are also existed; 11 families, 24 species, 1 variety, 30 taxa in total.