• Animal cells and systems
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• v.4 no.1
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• pp.1-7
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• 2000

The genus Dendronephthya, generally known as soft corals, is reported as an abundant and variable taxon. They mostly distribute in warmer waters of the Undo-Pacific Ocean region including Korea. In spite of their abundance and ecological importance as habitats of marine organisms, there are difficulties in the study of their identification and systematics because they have morphological variabilities and limited taxonomec characters. To resolve the problems, we attempted to elucidate the genetic relationships in the genus Dendronephthya by using random amplified polymorphic DNA (RAPD) analysis. This study was based on eight dendronephthian species and one Alcyoniidae species, Alcyonium gracillimum, as an outgroup. The results from all analysis suggest that they could be classified into four groups by the growth form and the anthocodial grades as follows: the first one,D. putteri and D. suensoni with the divaricate form and VI grade; the second one,D. sp.1 and D. sp.2 with the divaricate form and III or IV grade; the third one, D. gigantea and D. aurea being closer than D. spinifera with the glomerate form and III grade; the last one, D. castanea related to D. gigantea rather than D. putteri with the umbellate form and IV grade. Moreover, the divaricate form was separated from the group of the glomerate and umbellate form. At the intraspecies level, the types of the D. castanea, D. gigantea and D. spinifera were separated depending on the feature of spicules in the polyp head, and the coloration could not influence genetic variation. From this study, we can confirm that their morphological characters are compatible with the genetic variation, also RAPD analysis is a very useful method for resolving the systematic relationships of den-deonephthians.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.2
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• pp.211-215
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• 1983

Thirty eight varieties with high uniformity and clearance in grain quality among 70 colored soybeans collected from nation-wide provinces were investigated for their seed morphological and agronomic traits. As for seed morphological traits, grain volumetric size, grain weight, grain length, grain thickness, . hilum length and width were studied on the tendency of statistical dispersion and variations. As a result, four groups could be classified on the basis of 100 grains weight, so as small, medium, large, and super large groups, Also, as for agronomic traits, among others, the tendency of setting in flowering date, maturing date, yield components, and stem weight, stem length were studied on the basis of statistical inter-relationships between above mentioned characteristics. From the above, bigger variations were detected in weighing characters of soybean plants than in duration characters. And the flowering and maturing days showed significant relationships to the stem length, stem weight, also stem length and stem weight to the grain yield.

• Korean Journal of Plant Resources
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• v.12 no.4
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• pp.282-288
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• 1999

The experiment was carried out to determine the effects of soil condition on the agronomic characters and aromatic substances in cultivated Codonopsis Lanceolata. An increase of planting densities of Codonopsis Lanceolata. from 1 to 5 plant per pot resulted in the smaller root width, but root yield increased from 109.8g to 286.9g per 1/200pot. The width growth as soil water contents were higher in surplus soil water than that of cultivated deficit soil water. The contents of water, reducing sugar, crude protein and malic acid were higher in cultivated wild than in cultivated upland soil. The higher contents of volatile essential oils as 3-rnethylpentanoic acid and squalene was obtained at the normal soil moisture.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.24 no.1
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• pp.73-77
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• 1979

An artificial lodging was made at various growth stages of the soybean varieties Clark and KAS 100-3-1 to evaluate its effect on seed yield and other important agronomic characters. Results showed general increases in plant height and number of branches per plant whereas reductions in seed weight. number of nodes, pods and seeds per plant in the severly lodged plots. As compared to prevention of lodging, about 40 percent yield reduction was caused by the severe lodging treatrment. Furthermore, the most severe lodging before blooming resulted in about 66% yield loss.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2023.04a
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• pp.23-23
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• 2023

The Hairy labrador tea (Ledum palustre L. var. diversipilosum Nakai) is a evergreen small shrub, belonging to the Ericaceae and mainly distributed along the alpine areas of Hamgyeong-do in North Korea. Through seed physiological research on North Korean plants, we intend to obtain basic data for the development of mass propagation methods and use them for vegetation restoration. The internal and external morphological characters of the seed were observed using scanning electron microscopy or stereoscopy, and full seeds were selected through X-ray test. Seeds were cultured on a growth condition at 15/6℃ and 25/15℃ to examine the germination response according to temperature, and the number of germinated individuals was examined every 24 hours to calculate germination percentage and mean germination time. Low-temperature treatment (4℃) and hormone treatment (GA3) were performed to investigate the effect of dormancy breaking, and analysis of variance (ANOVA) was performed on the experimental results using SAS 9.4. The seeds of the Hairy labrador tea were elliptical-narrow in shape, and the epidermal cell wall pattern was reticulated. The final germination rate (FGP) was the highest at 58.9% under the condition of low temperature treatment at 25/15℃. The average number of days to germination (MGT) was the highest at 25.1 days without treatment at 15/6℃, and the average of the last germination days was confirmed to be about 13 days. As a result of low temperature treatment, it was confirmed that the final germination rate (FGP) increased by 43.3%. The significance of the final germination rate (FGP) was verified according to the pretreatment at 25/15℃.

• Korean Journal of Agricultural Science
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• v.2 no.1
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• pp.131-142
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• 1975

This study was carried out to define the variations of important quantitative characters and correlations among them accoding to the planted location under the shadow by planting density. The results obtained are summarized as follows; 1. Growth of leaf and stem of 6 rows and 8 rows planting plots was decreased at front and back rows, but that of root was increased at front row and also decreased at back row. However, at 4 rows planting plots, front row was better for the growth of leaf, stem and root. 2. Average root weight of 6 rows planting plot was 34.29g but that of 8 rows planting plot was ]8.20 g. And total weight of root per unit area was increased and quality of ginseng was better in 6 rows planting plot compaired with 8 rows. 3. Variation by planting locations under the shadow was smallest in stem diameter and highest in root length at 8 row planting plot, but at 6 rows planting plot, that was smallest in leaf blade and greatest in stem length. However, in 4 rows plant ing plot, variation of leaf length was smallest and that of root weight biggest. 4. In all Planting densities, root weight was significantly correlated with root diameter and high correlation was recognized between root diameter and stem diameter. 5. Rate of variations of all characters among plant individuals was different by planting location and that of correlations between quantitative Characters too.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.1
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• pp.39-43
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• 1995

In the culture of Vinyl mulching and Non mulching, growth, yield, and cotton hair's growth are studied at the different planting density to get a basic material for cotton culture and high yield bumper crop in the region of the South. And the results are following. Vinyl mulching is the best one at the strength, the number of boll bearing branches, the num-ber of bolls, the number of bolls per $m^2$ and all the other characters. Vinyl mulching and Non mulching have the greatest number of bolls per $m^2$ at the planting density of 70${\times}$10cm. Vinyl mulching has the highest seed cotton yield and the highest seed cotton yield per boll. Especially when planted at the density of 70${\times}$l0cm, Vinyl mulching and Non mulching have the highest seed cotton yield. Vinyl mulching's value is accepted in fiber length and lint percentage, the wider spacing in the row is, the longer fiber length is.

• Journal of the Korean Institute of Landscape Architecture
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• v.31 no.2
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• pp.83-93
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• 2003

This study was conducted for an understanding of a threatened plant species,“Penthorum chinense”, which is a vegetation structure and environmental characteristic in the southern part of Ibaraki, Japan. We selected distribution and contiguity area where P. chinense is not distributed and we set up 69 sites by the quardrat method. The surveyed general characters in each site include mean-height, mean-coverage, moisture condition water depth coverage and depth of litter layer. We calculated the degree of succession by the survey data and grasped the main distribution area, vegetation structure, growth environment of P. chinense by TWINSPAN classification and DCA ordination. The results of this study are as follows. First, P. chinense habitat was categorized into the riverside and abandoned paddy fields. The riverside was influenced by natural disturbance caused by flooding and drought. These conditions led to a poor P. chinense growth. The abandoned paddy fields as the artificial disturbance area have high potential value, because the area can preserve P. chinense growth space by succession control and water management. second, we executed TWINSPAN analysis based on vegetation coverage data of survey sites. The vegetation types were classified into the three categories: annual plant flora(P. chinense dominates in wet state), perennial plant flora(Solidago altissima dominates in dry state), and perennial plant flora(Phragmites communis dominates in wet state). Third, the data was ordinated by DCA. The sample sequences along the first and second DCA axes effectively reflected moisture condition, number of species, mean height, coverage of litter layer and degree of succession. Especially, P. chinense flora has the high correlation with moisture condition and number of species.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.3
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• pp.163-166
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• 2000

Cassia mimosoides var. nomame was grown at five phosphate rates (0, 5, 15, 25 and 35 kg/10a) at Cheju in 1998 to determine the influence of phosphate rate on growth, forage yield and quality. As phosphate rate increased from 0 to 35kg/10a, the plant growth was increased such as days to flowering, plant height, the number of branches and green leaves per plant, stem diameter and SPAD (Soil Plant Analysis Development) reading values of leaves but the number of withering leaves per plant decreased. Fresh forage yield was 3, 291kg/10a at 0 kg/10a of phosphate rate and increased 5, 200 and 5, 230 kg/10a at 25 and 35 kg/10a of phosphate level, respectively. Dry matter, crude protein and total digestible nutrients (TDN) showed the same tendency of changes as the fresh forage yield. Crude protein, crude fat, nitrogen free extract and TDN content increased but crude ash and crude fiber content decreased as the increasing of phosphate rate increased.

• Journal of Sericultural and Entomological Science
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• v.37 no.2
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• pp.121-126
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• 1995

The effects of oral application of fenoxycarb, the commercial formulation Insegar, to the selected developmental stages of the silkworm, Bombyx mori, was investigated. An oral application of the chemical to the silkworm from the 2nd- to the 5th-instar larvae delayed the larval development upto more than 40 days and increased the larval body weight in the range of 1.1 to 1.7 folds. When the chemical was orally applied to the final instar larvae, spinning and pupation were prevented, and consequently permanent larvae occurred. The weight of a cocoon and its shell of silkworm(bombyx, mori, L) increased following the application of fenoxycarb to the 2nd- and the 3rd-instar larvae.