• The Korean Journal of Ecology
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• v.20 no.5
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• pp.339-345
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• 1997

The Arisaema robustum, perennial non-stem herb, population in the temperate forest of Sanseong-ri, Joongbu-myeon, Kyonggi Province was studied for leaf pattern and leaf growth from 1993 to 1995. The area of each side leaflet was larger than that of the apical leaflet in 3-leaflet form plants. But there was no significant difference among the leaflets (apical, 1st side and 2nd side leaflet) in t-testing of the 5-leaflet form plants. The specific leaf area (SLA) of the 3-leaflet form plant was greater than that of the 5-leaflet form plant, and the difference was significant at 0.1%. But differences of SLA value among the leafleats of the same leaflet form plants were minor. The area of leaflets or total leaf area was inversely proportioned to the their SLA values. Especially, the correlation coefficients (CC) between leaf area and SLA in apical leaflets and side leaflets of the 3-leaflet form plant compared to the 1st side leaflets of the 5-leaflet form plants were significant at the level of 1%. The differences between two sides in the dry weight and area of leaflets starting from the apical leaflets were about 5%. The CC values between attributes of the petiole (length and dry weight) and those of leaf blades (dry weight, leaf area and SLA) were high and significant at a 1% level. Especially, The CC value between the dry weight of the petioles and that of the leaf blades was higher than any others (r=0.952). The morphologies of the leaf margins were entire, medium serrate and serrate, and the same plant showed the same type from year to year. The plants usually had one leaf and occasionally 2 leaves. 1-leaf plants usually had 3 or 5 leaflets and occasionally 2 or 4 leaflets. Each year, the ration of individuals having the same number of leaflets was 72%, and that of individuals having a different number of leaflets was 27.54% (an increase of 20.4% and a decrease of 7.1% respectively). In the individuals increasing in the number of leaflets, the ration of individuals shifting from the 3-leaflet from to the 5-leaflet form was 14%. The increase ration of leaf area per individual a year was 37%, and the increase ratios of the plants increasing in leaflets were 60-70% regardiness of leaflet increase. The ratios of leaflet length/breadth were about 1-2, and the variations of those were 0.182-0.286 each year (12-20%).

• Journal of the Computational Structural Engineering Institute of Korea
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• v.31 no.5
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• pp.243-250
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• 2018

In this paper, design technique using genetic algorithms(GA) for design optimization of composite leaf springs is presented here. After the initial design has been validated by the car plate spring as a finite element model, the genetic algorithm suggests the process of optimizing the number of layers of composite materials and their angles. Through optimization process, the weight reduction process of leaf springs and the number of repetitions are compared to the existing algorithm results. The safety margin is calculated by organizing a finite element model to verify the integrity of the structure by applying an additive sequence optimized through the genetic algorithm to the structure. When GA is applied, layer thickness and layer angle of complex leaf springs have been obtained, which contributes to the achievement of minimum weight with appropriate strength and stiffness. A reduction of 65.6% original weight is reached when a leaf steel spring is replaced with a leaf composite spring under identical requirement of design parameters and optimization.

• Korean Journal of Plant Taxonomy
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• v.53 no.3
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• pp.213-221
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• 2023

A newly recorded species, Boehmeria nakashimae Yahara, is confirmed for the first time to be distributed on forest edges on Jejudo Island, Korea. This species is known to be endemic to northern Kyushu, Japan. It is characterized by ovate to broadly ovate, elliptic-ovate, or sub-orbicular middle leaf shapes, serrulate-dentate and uniform margins, 17-29 teeth on one side, a short caudate or narrowly acute apex, dense glomerules at fruiting, and densely strigillose on the stems, both surfaces of the leaves, the perianth of staminate flowers, and achenes. Therefore, it is given the new name 'Je-ju-top-mo-si-pul' in Korean based on its serrulate-dentate leaf margin and geographical distribution. A description, photographs, illustrations, and keys of related taxa in Korea are provided.

• Journal of Forest and Environmental Science
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• v.37 no.4
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• pp.338-340
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• 2021

Morus alba, known as White Mulberry, is one of the most common species of mulberry found in South Korea, along with M. australis, known as Korean Mulberry. During a routine survey to investigate fungal diseases on deciduous broad-leaved trees in 2020, leaf spots were consistently observed on the White Mulberry in Sejong-si (36°30'12.8"N 127°17'34.5"E) and Wonju-si (37°15'29.6"N 128°11'37.9"E), South Korea, with a disease incidence of approximately 70 to 80%. Symptoms included circular, tan or necrotic lesions surrounded by a dark margin on leaves, which, in some cases, the lesions coalesced to form relatively large necrotic regions. The pathogen was successfully isolated from M. alba, and was identified as Cladosporium pseudocladosporioides based on the phylogenetic analysis and morphology. To the best of our knowledge, this is the first report of leaf spot disease on M. alba caused by C. pseudocladosporioides in South Korea.

• Research in Plant Disease
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• v.11 no.1
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• pp.77-79
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• 2005

Leaf blight of kudzu was found in Jeonbuk province in 2002. Water-soaked lesion appeared on leaves, and young stems and gray green blight sypmtom expanded from margin to main vine of leaves. As the disease became severe, blighted leaves and shoots turned dark brown and then collapsed. The causal pathgen showed initially white aerial mycelium and turned brown to gray. Mycelia were branched at 90o angles and multinucleate in one cell. It formed sclerotia on PDA. Slerotia were irregular, globose and 0.5~3.0 mm in diameter. The causal fungus of leaf blight was identified as Rhizoctonia solani Kuhn based on the cultural and morphological characteristics. This is the first report on leaf blight of kudzu caused by R. solani in Korea.

• Korean Journal of Plant Taxonomy
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• v.42 no.2
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• pp.150-156
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• 2012

While preparing a floristic study of Korean hepatics, we discovered the six unrecorded species of Lejeuneaceae from Mt. Seolak, Mt. Gaya, Geojedo, Wando and Gageodo. Archilejeunea kiushiana, Drepanolejeunea angustifolia, Lejeunea aquatica, Lejeunea otiana, Leucolejeunea japonica, and Spruceanthus semirepandus, are reported here. A. kiushiana was characterized by unlobed underleaves, homogeneous oil-bodies, and four to six perianth-keels. D. angustifolia is similar to D. ternatensis, but it differs in the dorsal margin of the leaf-lobe, which is entire or denticulate, spines never present, and leaf cells smooth or with minute dorsal bulging. L. aquatica is similar to L. japonica in that it has a wider and similar shape (wider than long) of its underleaves and has homogeneous oil-bodies. The former, however, has minute leaf-lobules (5-15 cells), 1/10 to 1/5 the length of the leaf-lobe, versus leaf-lobules 1/4 to 1/3 the length of the leaf-lobe. L. otiana is similar to L. kodamae in that it has a large and acute first tooth of the leaf-lobule but differs in having plain leaf-lobules obliquely quadrate and an indistinct second tooth. Drepanolejeunea (Spruce) Schiffn. is widely distributed in tropical and subtropical regions (Mizutani, 1961). L. japonica is characterized by entire underleaves; one large, coarsely segmented oil-body per leaf cell; and a large second tooth of the leaf lobule, two to six cells long, and two to three cells wide at the base. S. semirepandus is widely distributed in tropical and subtropical regions in Asia. This species is characterized by small homogeneous and numerous oil-bodies, up to 10 smooth perianthkeels, and leaf-lobe acute at the apex.

• Korean Journal of Oriental Medicine
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• v.12 no.2 s.17
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• pp.63-73
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• 2006

In the original plant of Arisaematis Rhizomas, the features of external and internal shape of Arisaema amurense var. serratum $N_{AKAI}$ and A. amurense $_{MAXIM}$. are as follows. 1. In the external shape of original plant, Arisaema amurense var. serratum $N_{AKAI}$ has high stem, an oval-elliptic leaflet and a serrate leaf margin. But A. amurense $M_{AXIM}$ has a relatively low stem, an upside oval leaflet and no serrate leaf margin. 2. On the herbs character of original plant, Ansaema amurense var. serratum $N_{AKAI}$ is small in height and diameter, but A. amurense $M_{AXIM}$ is relatively large in height and diameter. 3. On the gathered herbs character of original plant, the section of Arisaema amurense var. serratum $N_{AKAI}$ is brightly white, easily spilt and strong scent. But the section of A. amurense $M_{AXIM}$ is thin yellowish brown, not easily spilt and weak scent. Also the grade of gathered herbs, both can be classified by diameter and external scent. 4. In the current herbs character, Korean and Sichuan Province products are irregullar shape and have no scent, Jilin Province products are regular shape. Also, Guangxi Province products are small size and concave in one side, Hebei Province products are irregular size and shape. 5. In internal shape of original plant, epidermal cell of Arisaema amurense var. serratum is very tight. With the except of micro difference in parenchyma cell of cortex, on the whole there are nearly no differences with A. amurense $M_{AXIM}$. Also, samely in the internal shape, according to collecting sites, epidermis exhibits a lot layer in curving state and secreting duct is developed and vascular bundle and exists between parenchyma cell of cortex. In the future, additional study is needed to distinguish herb and effect between same genus-degree of relatedness.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.2
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• pp.192-198
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• 1999

A pot experiment was carried out to investigate the effect of boron on the growth, symptom, yield, and content of boron in Perilla(Perilla frutescens var. japonica HARA), Melon(Cucumis melo L.) and Cucumber(Cucumis sativus L.). The results obtained are as follows. Perilla. melon and cucumber uptake a lot of boron from the soil, and toxic effects of boron result in leaf tip yellowing by progressive necrosis. Yield of perilla, melon and cucumber are decreased at the $3{\sim}5mg\;kg^{-1}$, $5{\sim}10mg\;kg^{-1}$ of boron applicated in soil, respectively. Boron content in the leaf is the highest among various parts plant, and the tip and margin of the leaf contained more boron than central part of the leaf. Boron applicated was moved and accumulated to the plant and soil.

• Korean Journal of Plant Resources
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• v.33 no.4
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• pp.398-403
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• 2020

Plagiothecium platyphyllum Mönk (Plagiotheciaceae), a species unrecorded previously in the moss flora of the Republic of Korea (South Korea), was collected in the Surak stream of Mt. Daedun in Jeollabuk-do Wanju-gun Sanbuk-ri. This species was known to be distributed around China, Japan, North Korea, and Europe. The morphological characters of P. platyphyllum's leaf are ovate-lanceolate, and mostly asymmetric, 2.0~2.5 × 1.0~1.4 mm. The margin of the leaf is entirely below and weakly serrulated near the apex. The costae parts are double, unequal, with one branch reaching to the mid-leaf. Median leaf cells are linear-rhomboidal, 80~127 × 10~16 ㎛ and alar cells are rectangular. Central strand is developed in the core of the stem.

• Korean Journal of Plant Taxonomy
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• v.42 no.2
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• pp.126-140
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• 2012

We conducted principal component analyses using the thirty two quantitative characteristics of Najas from South Korea to examine the morphological variation and diagnostic characteristics. As a result of our investigation and the morphometric analyses, each taxon could be identified using the leaf width, shape of the leaf sheath, number of teeth on the leaf margin, number of anther cells, number of areoles in each longitudinal row of seeds, and the ratio of the areole width to the length. Dioecious Najas marina was clearly distinguished from the other monoecious taxa (N. graminea, N. gracillima, N. minor, N. oguraensis, and N. orientalis) by the larger size of the stem, the leaf, the flower and the fruit. The monoecious taxa could be identified using vegetative characteristics except for N. minor and N. oguraensis, which were distinct from each other according to the locule number in the staminate flower.