• Applied Microscopy
• /
• v.16 no.2
• /
• pp.49-60
• /
• 1986

Ultrastructures of the large and elongated cells (idioblasts) in the haustorium of a parasitic angiosperm, Cuscuta australis R. Brown growing on the host plant, Trifolium repens L. were investigated by the electron microscopy. The idioblasts were characterized by the presence of a large nucleus, small vacuoles, and dense cytoplasm including a number of various cell organelles such as ribosome, rough endoplasmic reticulum(r-ER), mitochondrion, dictyosome, proplastid, multilamellar structure(MLS), microfilament bundle(MFB), and cytosegresome. Therefore, it is suggested that the idioblasts are metabolical1y very active. Particularly, MLS, MFB, and cytosegresome observed in this study did not appear in the haustorial cells of the other parasitic angiosperms. MLS was transformed into vacuole and also incorporated with cell wall. MFB composed of microfilaments, about each 7.5 nm in diameter, was observed in nucleus and also cytoplasm. Some types of MFB were distinguished on the basis of arrangement of microfilaments. A part of cytoplasm sequestered by stacked cisternae of smooth ER(s-ER), cytosegresome, was altered into a vacuole which was formed by digestion of the sequestered cytoplasm and of cisternae of s-ER. Cell organelles such as MLS, MFB, and cytosegresome were discussed in relation to the metabolic control of the idioblasts.

• Journal of Environmental Science International
• /
• v.17 no.10
• /
• pp.1081-1092
• /
• 2008

This study was conducted to provide scientific information for establishing efficient and systematic measures for nature conservation and management in Manjang-gul lava tube. The number of vascular plants was 204 taxa (82 families, 176 genera, 144 species, 1 subspecies, 26 varieties and 1 forma). Of those, pteridophyte were 5 families, 12 genera, 14 species and 1 variety and gymnosperm were 4 families, 6 genera, 5 species and 1 variety. Seventy three families, 149 genera, 157 species, 1 subspecies, 24 varieties and 1 forma in angiosperm composed of 62 families, 123 genera, 137 species, 1 subspecies, 17 varieties and 1 forma in dicotyledon and 11 families, 26 genera, 20 species and 7 varieties in monocotyledon. The number of naturalized plants was 9 families, 17 genera, 18 species and 3 varieties, totaling 21 taxa.

• Journal of the Korean Wood Science and Technology
• /
• v.15 no.1
• /
• pp.22-55
• /
• 1987

This study was executed to offer the basic data needed to plywood industry in Korea for the future based on microscopic wood features as our previous paper reported by the macroscopic features. Microscopic wood characteristics for 50 species selected by the viewpoint of possible utility in future were examined and described by the species. Also, keys for the identification based on microscopic features were briefly prepared and presented by gymnosperm and angiospenn respectively.

• Journal of the Korean Wood Science and Technology
• /
• v.23 no.3
• /
• pp.82-87
• /
• 1995

Anatomical characteristics of genus Platycarya, Juglans and Pterocarya of Juglandaceae occurring in Korea were described and coded based on the IAWA list. Juglandaceae are ring-porous or semi-ring-porous. Vessels have simple perforation plates and helical thickenings in some genus. Axial parenchyma cells were abundant, most apotracheal but rarely paratracheal and rays with 1-5 seriate. Platycarya is ring-porous wood with 2-3 rows of vessels in the pore zone. Helical thickenings were found only in small vessel of latewood. Axial parenchyma were commonly diffuse-in-aggregates or vasicentric. Rays 3-5 seriate. belonging to Kribs' heterogeneous II or III type with frequent occurrence of rhomboidal crystals. Juglans are semi ring-porous with few vessels in $mm^2$ and pores are commonly solitary. Axial parenchyma were diffuse-in-aggregate or marginal. Rays were mostly homocellular and 3-5 seriates. Pterocarya is similar to Juglans in anatomical features but the reticulate parenchyma consisting of 1 layer on transverse section and biseriate rays.

• Journal of Life Science
• /
• v.19 no.8
• /
• pp.1016-1022
• /
• 2009

Tapetum is the tissue in which nutrients are supplied to the developing microspore in angiosperm anther. At tetrad stage of microspore, the tapetal cells show maximum development, but they began to be degenerated by apoptotic programmed cell death (PCD) after sporopollenin accumulation in the pollen wall. The initial step of PCD was observed as vacuolar fusion. After that, cytoplasmic condensation and nuclear fragmentation followed. Lipid droplets are degenerated at a relatively late stage of PCD, and orbicular bodies are the last remains in tapetal cells. The cell wall was relatively resistant against vacuolar enzymes in tapetal cells; it was considered the last structure remaining during programmed cell death of tapetum in ginseng anther.

• Korean Journal of Plant Taxonomy
• /
• v.48 no.3
• /
• pp.201-205
• /
• 2018

Carex L. (Cyperaceae) is the largest angiosperm genus in the temperate zones with more than 2,000 species worldwide. Unusual chromosome structures, called holocentric chromosomes, have been postulated to contribute to species diversity in the genus. In Korea, this genus has the greatest number of species, but chromosome information as it pertains to the taxa is mostly unknown. Here, we report meiotic chromosome numbers of five Carex taxa in Korea. The following observations are made: Carex jaluensis Kom. ($n=27_{II}$, $28_{II}$, $29_{II}$, $30_{II}$), C. japonica Thunb. ($n=28_{II}$, $29_{II}$), C. planiculmis Kom. ($n=30_{II}$), C. miyabei Franch. ($n=33_{II}$, $36_{II}$), C. neurocarpa Maxim. ($n=51_{II}$, $53_{II}$, $54_{II}$). Except for C. planiculmis, all of the species exhibit variations in chromosome numbers within individuals and/or taxa. The findings with regard to chromosome number diversity in Carex suggest that chromosome number variation (aneuploidy, agmatoploidy and/or symploidy) plays an important role in the richness of the species in the genus. Further cytological investigations are needed for a better understanding of sedge diversity in Korean flora.

• Korean Journal of Plant Taxonomy
• /
• v.53 no.3
• /
• pp.181-200
• /
• 2023

Owing to the rapid development of sequencing technologies, more than 1,000 plant genomes have been sequenced and released. Among them, 69 Korean plant taxa (85 genome sequences) contain at least one whole-genome sequence despite the fact that some samples were not collected in Korea. The sequencing-by-synthesis method (next-generation sequencing) and the PacBio (third-generation sequencing) method were the most commonly used in studies appearing in 65 publications. Several scaffolding methods, such as the Hi-C and 10x types, have also been used for pseudo-chromosomal assembly. The most abundant families among the 69 taxa are Rosaceae (10 taxa), Brassicaceae (7 taxa), Fabaceae (7 taxa), and Poaceae (7 taxa). Due to the rapid release of plant genomes, it is necessary to assemble the current understanding of Korean plant species not only to understand their whole genomes as our own plant resources but also to establish new tools for utilizing plant resources efficiently with various analysis pipelines, including AI-based engines.

• Genomics & Informatics
• /
• v.20 no.4
• /
• pp.40.1-40.8
• /
• 2022

The concepts of phylogeny and floral genetics play a crucial role in understanding the origin and diversification of flowers in angiosperms. Angiosperms evolved a great diversity of ways to display their flowers for reproductive success with variations in floral color, size, shape, scent, arrangements, and flowering time. The various innovations in floral forms and the aggregation of flowers into different kinds of inflorescences have driven new ecological adaptations, speciation, and angiosperm diversification. Evolutionary developmental biology seeks to uncover the developmental and genetic basis underlying morphological diversification. Advances in the developmental genetics of floral display have provided a foundation for insights into the genetic basis of floral and inflorescence evolution. A number of regulatory genes controlling floral and inflorescence development have been identified in model plants such as Arabidopsis thaliana and Antirrhinum majus using forward genetics, and conserved functions of many of these genes across diverse non-model species have been revealed by reverse genetics. Transcription factors are vital elements in systems that play crucial roles in linked gene expression in the evolution and development of flowers. Therefore, we review the sex-linked genes, mostly transcription factors, associated with the complex and dynamic event of floral development and briefly discuss the sex-linked genes that have been characterized through next-generation sequencing.

• Korean Journal of Environmental Biology
• /
• v.17 no.4
• /
• pp.503-512
• /
• 1999

The morphological variations and habitat environment of the Zostera asiatica Miki (Zosteraceae) were examined in the waters off the eastern coast of Korea and Akkeshi Bay of Japan. In this study, we report new habitat of Z. asiatica along the eastern coast of south Korea； Gonghunjin, Donghori, Youngdong and Chilpo. Z. asiatica is found at the depth of 8∼15 m in these areas. However, Z. asiatica grows at the depth of 3 m in Akkeshi Bay of Japan. The sediment of habitats in the eastern coast of Korea were principally composed of sand. The stems were 64.0∼75.7 cm long in mature plants with flowering shoots and the leaves were 11.0∼15.0 mm wide for Korean populations. Plants from Akkeshi Bay of Japan had stems of 187.0∼234.0 cm in length. The difference in size are considered to be due to the depth of habitats. In spite of the significant morphological difference between Korea and Japan population of Z. asiatica, there was no difference in ITS sequences.

• Korean Journal of Plant Taxonomy
• /
• v.45 no.3
• /
• pp.278-297
• /
• 2015

With the development of the internet and international agreements such as the Convention on Biological Diversity (CBD) and the Convention on International Trade in Endangered Species (CITES), Korean researchers frequently encounter scientific names of foreign species, and these are named on a case-by-case basis in Korean without any standard naming method. Therefore, standard Korean names for entire orders and families in the world are required for better communications in Korea. However, there have been no comprehensive discussions of the standardization of Korean names for the orders and families found in the world. In this study, we 1) compare the Korean names of orders and families in the references, 2) discuss naming methods in Korean for foreign taxa, and 3) then suggest standard Korean names for the orders and families in the APG III, which is an up-to-date angiosperm classification system. This study will be a starting point for the national standardization of Korean names for orders and families found throughout the world.