• Current Optics and Photonics
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• v.2 no.5
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• pp.460-467
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• 2018

Three-dimensional (3D) refractive-index (RI) imaging and quantitative analyses of angiosperm pollen grains are presented. Using optical diffraction tomography, the 3D RI structures of individual angiosperm pollen grains were measured without using labeling or other preparation techniques. Various physical quantities including volume, surface area, exine volume, and sphericity were determined from the measured RI tomograms of pollen grains. Exine skeletons, the distinct internal structures of angiosperm pollen grains, were identified and systematically analyzed.

• Proceedings of the Botanical Society of Korea Conference
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• 1999.04a
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• pp.6-6
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• 1999

• Journal of the Korean Society for Nondestructive Testing
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• v.23 no.5
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• pp.480-487
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• 2003

To improve environmental control in various plants, signal characteristics of plants have been studied by a nondestructive technique. In this paper, the acoustic emission (AE) from plants was analyzed for water stress dependency. AE signals were taken from gymnosperm and angiosperm. AE sensor detected AE signals from the plant stem underneath the plant surface below the sensor. AE hit-event counts in daytime were more than those in night time, and it was found that the daily hit counts pattern was strongly affected by the water stress in the plant. frequency bands of AE signals from the angiosperm was different from those from the gymnosperm. Frequency bands of AE in outdoor condition were in accord with those in indoor having similar conditions.

• Journal of Forest and Environmental Science
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• v.32 no.1
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• pp.27-38
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• 2016

A total of 680 angiosperm plant species under 433 genera of 115 families have been recorded from the Southeast offshore Islands of Bangladesh including Nijhum Dwip, Hatiya, Sandwip, Kutubdia, Maheshkhali, Sonadia and Saint Martin's. Magnoliopsida is represented by 92 families, 344 genera and 546 species, whereas Liliopsida is represented by 23 families, 89 genera and 134 species. Habit analysis shows that herbs, shrubs, trees and climbers were represented by 331, 117, 169 and 63 species respectively. The plant diversity of the southeast offshore islands is under great risk because of many threats including natural and manmade. The aims of the present study are investigation, accumulation and documentation of the angiosperm plants of the area.

• Journal of Plant Biology
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• v.21 no.1_4
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• pp.39-44
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• 1978

Acid phosphatase activities were analyzed in $\mu\textrm{g}$ tissue samples from an angiosperm parasite (Cuscuta cephalanthi) and its host plant (Hedera helix) by a fluorometric microtechnique. The apex and the coiling portion of the parasite axis exhibited greater enzyme activies than other portions of the hypha. Acid phosphatase activity in the haustorium was 2-3 times that in the hyphal axis. The vascular bundles of the normal host exhibited the greatest enzyme activity. The acid phosphatase activity in the host infected by the parasite decreased to the activity level of the haustorium.

• Proceedings of the Zoological Society Korea Conference
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• 2001.10a
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• pp.87.1-87
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• 2001

No Abstract, See Full Text

• Korean Journal of Plant Resources
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• v.22 no.1
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• pp.71-77
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• 2009

Antioxidative activity and ${\alpha}$-amylase inhibitory activity were investigated in the methanol extracts of 289 species of angiosperm plants native to Jeju Island in order to select the plant species containing bioactive materials for functional foods or medicines. The antioxidative activity, estimated by the DPPH radical scavenging capacity, was high in the galla of Rhus chinensis, the fruit of Platycarya strobilacea, and the stem of Cedrela sinensis. Particularly, the antioxidative activity of Rhus chinensis galla (94.2${\pm}$0.8%) was very high even though compared to those of BHA (61.7${\pm}$0.6%) and ascorbic acid (53.6${\pm}$0.7%). The ${\alpha}$-amylase inhibitory activity was 80% or above in 9 species including Cornus macrophylla (stem, leaf), Distylium racemosum (leaf) and Vaccinium oldhami (leaf). These results suggest that these plants could be potentially utilizable to develop bioactive materials for functional foods or medicines.

• Journal of the Korean Society for Nondestructive Testing
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• v.23 no.3
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• pp.198-204
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• 2003

A basic experiment was performed to control tile plant growth using acoustic emission technique considering the environmental conditions for plant. At a dry soil condition, the signals due to the cavitation from xylem of angiosperm and gymnosperm were mainly detected. The strong signal from xylem and the weak signal from plasmodesmata and casparian strip were detected at the same time after distilled water was provided. Two signals after providing tile acid and distilled water were contrary to each other. The wind, number of leaf, music, temperature and humidity affected the acoustic emission count from plants but the frequency ranges of the detected signals were the same.

• Korean Journal of Plant Taxonomy
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• v.40 no.1
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• pp.1-15
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• 2010

Recognizing a basal group in a taxon is one of the most important factors involved in understanding the evolutionary history of that group of life. Many botanists have suggested a sister to all other angiosperms to understand the origin and rapid diversification of angiosperms based on morphological and fossil evidence. Recent technical advances in molecular biology and the accumulation of molecular phylogenetic data have provided evidence of the extant basal-most angiosperm which is a sister to all other angiosperms. Although it is still arguable, most plant taxonomists agree that Amborella trichopoda Baill., a species (monotypic genus and monotypic family) distributed in New Caledonia, is a sister to all other extant angiosperms based on evidence from the following molecular approaches: 1) classical phylogenetic analyses based on multiple genes (or DNA regions), 2) analyses of a tree network of duplicated gene families, and 3) gene-structural evidence. As an alternative hypothesis with relatively minor evidence, some researchers have also suggested that Amborella and Nymphaeaceae form a clade that is a sister to all other angiosperms. Debate regarding the basal-most angiosperms is still ongoing and is currently one of the hot issues in plant evolutionary biology. We expect that sequencing of the whole genome of Amborella as an evolutionary model plant and subsequent studies based on this genome sequence will provide information regarding the origin and rapid diversification of angiosperms, which is Darwin's so called abominable mystery.

• ALGAE
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• v.17 no.1
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• pp.59-68
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• 2002

A phylogenetic affinity between charophytes and embryophytes (land plants) has been explained by a few chloroplast genomic characters including gene and intron (Manhart and Palmer 1990; Baldauf et al. 1990; Lew and Manhart 1993). Here we show that a charophyte, Spirogyra maxima, has the largest operon of angiosperm chloroplast genomes, rpl23 operon (trnⅠ-rpl23-rpl2-rps19-rpl22-rps3-rpl16-rpl14-rps8-infA-rpl36-rps11-rpoA) containing both embryophyte introns, rpl16.i and rpl2.i. The rpl23 gene cluster of Spirogyra contains a distinct eubacterial promoter sequence upstream of rpl23, which is the first gene of the green algal rpl23 gene cluster. This sequence is completely absent in angiosperms but is present in non-flowering plants. The results imply that, in the rpl23 gene cluster, early charophytes had at least two promoters, one upstream of trnⅠ and and another upstream of rpl23, which partially or completely lost its function in land plants. A comparison of gene clusters of prokaryotes, algal chloroplast DNAs and land plant cpDNAs indicated a loss of numerous genes in chlorophyll a+b eukaryotes. A phylogenetic analysis using presence/absence of genes and introns as characters produced trees with a strongly supported clade containing chlorophyll a+b eukaryotes. Spirogyra and embryophytes formed a clade characterized by the loss of rpl5 and rps9 and the gain of trnⅠ (CAU) and introns in rpl2 and rpl16. The analyses support the hypothesis that the rpl23 gene cluster and the rpl2 and rpl16 introns of land plants originated from a common ancestor of Spirogyra and land plants.