• Applied Biological Chemistry
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• v.19 no.4
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• pp.189-201
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• 1976

In an effort to develop a microbial in secticide, B. thdringiensis var. thuringiensis was cultured in the medium composed of cocoon-cooked water from a filature. The results obtained are summarized as followss : (1) Bacillus thuringiensis is a bacterium producing a ${\delta}-endotoxin$ especially toxic to lepidopterous insects and a thermostable exotoxin harmful to dipterous insects. (2) With a view to utilizing the cocoon-cooked water discarded from the filature, as a nutrient source in the B. thuingiensis culture, it was analyzed to contain large amounts of various minerals and protein (7.5 mg/ml) believed to be extracted from the pupae. (3) A large amount of the ${\delta}-endotoxin$ can be obtained most cheeply by using cocoon-cooked water instead of distilled water in preparing GYS and citrate salts media. (4) The largest amount of a mixture of the vegetative cells, spores, and crystals was obtained by addition of 8 gr/l of glucose to the GYS medium. (5) The growth of the bacterium was far better, when leucine, isoleucine, and valine were added all together to the citrate salts medium to the concentration of $1.25{\times}10^{-3}M$. (6) The best growth was observed by addition of Na-glutamate to the citrate salts medium to the concentration of $2.5{\times}10^{-3}M$. (7) The optimal culture time ranged from 9 to 15 days. (8) The highest mortality was shown in Pieris rapae Linne with a pH of the total body extract of 8.4, whereas Dendrolimus spectabilis Butler and Bombyx mori Linne with lower pH's were less susceptible to the ${\delta}-endotoxin$. (9) The presence of the thermo stable exotoxin was confirmed by the fact that the supernatant of the culture was very toxic to the Drosophila melanogaster tested.

• Korean Journal of Agricultural Science
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• v.13 no.2
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• pp.151-156
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• 1986

Two soybean cultivars different in plant type, Hwanggeumkong and Suweon-125, were planted under two different planting densities to investigate the proper planting densities after barley crops. The results obtained are summarized as follow: 1. No apparent varietal differences due to the planting densities were observed in flowering time and maturity. 2. The number of nodes of main stem showed significant differences between plant types, while they were not significantly different between planting densities. The number and length of branches per plant were apparently decreased as the planting densities were higher. 3. The number of pods per plant, and number and weight of grain per plant decreased as the planting densities increased and they showed also significant differences between planting densities. However, the number of pods, and number and weight of grain per unit land area were increased as the planting densities increased. 4. The grain yield per 10a showed significant cultivar difference under different planting densities. The Hwanggeumkong, determinate type, showed highest grain yield at the planting densities of $60{\times}7.5cm$, while Suweon-125, indeterminate type, highest at the planting densities of $60{\times}5.0cm$.

• Korean Journal of Medicinal Crop Science
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• v.5 no.4
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• pp.266-275
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• 1997

Anemarrhena asphodeloides BUNGE is one of important medicinal crops, which has been collected or/and cultivated for its rhizomes. The main medicinal ingredient of the A. asphodeloides Bunge rhizomes is a saponin, which is known to have medical values for diaphoresis, sedatives and biuresis. However, studies on cultural methods and breeding works on this plant have not been made in detail. To increase productivity and to improve quality of crops, it is important to collect cultivated and wild lines, to classify them based on morphological and genetic characteristics, and to select superior pure lines at first. Therefore, total 20 A. asphodeloides lines collected were cultivated at the fieldof Chungnam Provincial Administration of Rural Development in 1995 to study the agronomic characteristics and to classify them based on morphological characteristics. Characteristics related with reproductive organ such as the number of spikes per plant and peduncle length showed greater variations than vegetative organrelated characteristics such as leaf length and rhizome length based on the coefficient of variation. Vigorous shoot growth resulted in better development of reproductive organs such as peduncle length and number of spikes per plant. However, the development of spikes was negatively correlated with chlorophyll content. Characteristics of underground parts were more significantly correlated with spike characteristics than aerial part characteristics. A. asphodeloides tested in this study were classified into 2 groups (group A and group B) based on centroid linkage cluster analysis. Group A showed more vigorous shoot growth with more leaves and spikes per plant, longer peduncle length, thicker peduncle diameter and higher shoot dry weight than group B. Group A could be further classified into 2 sub-groups based on leaf size, spike length and peduncle diameter, while group B also could be classified based on number of leaves, number of spikes and shoot dry weight.

• Korean journal of applied entomology
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• v.25 no.2 s.67
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• pp.63-70
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• 1986

Severity of incidence of white rot on apple fruit ranged from 5 to 16% and averaged 9% over major apple growing area in 1981. An isolate of Botryosphaeria ribis obtained from rotted apples developed lesions on leaves, branches and fruits of apple, pear, peach and grape in a series of wound inoculation test. B. ribis grew well on both potato sucrose agar and oatmeal agar. The best condition for vegetative growth on these two media was at $25{\sim}30^{\circ}C$ pH 4 and $10{\sim}15%$ sucrose content under light illumination. Rot development on fruit was first observed in the orchard at early August when sugar content in fruit reached 9.0%. Thereafter, number of rotted apples increased as sugar content increased. There was no correlation between the pH of juice of fruit and rot incidence. Infection on fruit began to occur as early as mid-June when young fruits were formed and infections were continued until harvest. When apple fruits were collected at 10-day intervals from the orchard beginning from early June and were wound-inoculated with B. ribis, rot lesion developed regardless of the stage of fruit growth. Incidence of white rot in the orchard was severe on Golden-delicious and Yukou, intermediate on Aoli, Fugi and Indo, and least on Jonathan and Red-delicious.

• Korean Journal of Weed Science
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• v.8 no.1
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• pp.23-27
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• 1988

This experiment was conducted to determine germination ability, life cycle, regrowth ability of Portulaca oleracea L. The newly harvested seeds from P. oleracea flowered before July 15 were able to germinate, but percent germination decreased markedly as the flowering time was later than July 15, showing no germination of seed collected at Sept. 12 which were flowered at August 30, 76.5% of seeds can be germinated in the light as seed stored in room condition for 90 days, but in dark condition, it needed 2 years of seed storage for germination. Low temperature treatment at $2^{\circ}C$ for 5 days enhanced seed germination of P. oleracea in both light and dark conditions. The maximum vagetative growth was observed at 30 to 75 days after seeding. The late seeding time such as July 1 shortened the period of vegetative growth. However, regardless of the seeding times, the first flowering was observed at about 40 days after seeding. Leaf numbers, shoot lengths, fresh and dry weights were greatly affected by the seeding dates, showing that the earlier seedings produced significantly higher shoot length, fresh and dry weight, leaf numbers and branch numbers than those of the late seedings. When all branches were removed on 68 days after seeding, their regrowth ability was 50.3% and cuttaged branches showed 78.1% regrowth as compared to intact plant.

• Horticultural Science & Technology
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• v.33 no.1
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• pp.149-154
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• 2015

A new Phalaenopsis cultivar 'SM 333' was bred by Sangmiwon Orchid, Korea, which produces young plants through tissue culture techniques. The new cultivar 'SM 333', showing the phenotype of multiflora with pink color and small, multibranching-type characteristics, was derived from crossing between Phalaenopsis 'Odoriko' and 'Be Tris'. An elite individual number '02-03-33' later termed 'SM 333' was selected among about 300 individual progenies, based on an intensive selection process covering vegetative and flowering distinctiveness over more than 2 years. In year 2004-2005, the 1st and 2nd characteristic analyses were carried out through performance and uniformity tests. 'SM 333' shows flower color that is bright clean pink (RHS # RP69D) and flower shape that is formal type with 5.0 and 5.8 cm in flower height and width, respectively. 'SM 333' is regarded as raceme flower type suitable for the small casual flower market. The leaves of 'SM 333' grow horizontally and about 20.8 cm in length and 6.5 cm in width. This cultivar also possesses no genetic variation, and is amenable to fast in vitro propagation and easy growth due to its vigorous growth habit. This 'SM333' was registered (Reg. # 2916) with Korea Seed & Variety Service (KSVS) on 1st December, 2009, and the plant breeder's right is currently controlled by Sangmiwon Orchid Company, Korea.

• Horticultural Science & Technology
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• v.29 no.1
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• pp.10-15
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• 2011

The influence of root zone temperature to the induction of inflorescence and growth of Phalaenopsis was investigated. Root zone temperatures were 15, 20, 25, and $30^{\circ}C$, while the air temperature was kept over $28^{\circ}C$ during three months. $CO_2$ uptake, fresh weight, dry weight and branched root number of Phalaenopsis were highest at $25^{\circ}C$ and lowest at $15^{\circ}C$. But, the anthocyanin content was highest at $15^{\circ}C$ and lowest at $25^{\circ}C$. Inflorescence was not induced by root zone cooling temperature below $25^{\circ}C$ for three months. The concentrations of K, Ca and Mg in leaves were changed according to the root zone temperature, but those of N and P were not changed. K content was high at $20^{\circ}C$, whereas Ca and Mg contents were high at $25^{\circ}C$ root zone temperature. This study indicates that Phalaenopsis perceives temperature by shoot and the optimum root-zone temperature for the vegetative growth is $25^{\circ}C$.

• Journal of Korean Society of Forest Science
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• v.20 no.1
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• pp.45-50
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• 1973

This study was investigated the methods of vegetative propagation for new Lespedeza varieties. Experimental matterials were used 6 Lespedeza species; L. maximowiczii, L. cyrtobotrya, L. angustifolioides, L. bicolor, L. maximowiczii var. tomentella, and L. japonica var. intermedia. In April a year branches were cut 15-20cm length and 3-4mm thickness and planted in sand bed (depth 150cm) to be sterilized by the 0.1% solution of Uspulun. And then the cutting beds were irrigated and shaded. The results are as follows. 1. The rooting rates of the cuttings could be found so variable among varieties from 69% of L. maximowiczii var. tomentella to 50.3% of L. japonica var. intermedia. 2. The growth performance showed statistically significant difference at 1% level among varieties. L. maximowiczii was the best, while L. japonica var. intermedia showed the wrost growth performance of them. 3. The average number of roots with more than 5 cm length per stock was revealed statistically significant difference at the 1% level among varieties from the greatest number of 6.4 of L. maximowiczii var. tomentella to the smallest number of 2.3 of L. japonica var. intermedia. 4. Total average length of the roots per stock was statistically significant so different at 1% level from the longest 279.8cm of L. maximowiczii var. tomentella to the shortest 41.1cm of L. japonica var. intermedia. 5. The average ndules with more than 1 mm in diameter per stock was statistically significant so different at 1% level among varieties from the greatest number of 34.4 of L. maximowcizii to the smallest numqer of 4.6 of L. japonica var. intermedia.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.4
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• pp.407-412
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• 1985

The effect of potash applied with different sources of nitrogen was experimented in pot soil culture on chinese cabbage (Brassica Pekinensis Rupr, Var. Fall 1984: Sammi Garak, Spring 1985: Jungang Summer lab.) in the fall, 1984 and in the spring, 1985. Results obtained are as follows; 1. Ammonium nitrate increased the yield of chinese cabbage more than urea did, and the effect of yield increase by ammonium nitrate was greater in the fall cultivation than in the spring. 2. The yield of chinese cabbage was positively correlated with the contents of K in the first (May 17, 1985) and second (June 9, 1985) thined cabbages (dry matter). It was also positively correlated with $NO_3-N$ content of the first thined cabbage and with K/Ca+Mg m.e, ratio of outer leaves of the harvested (June 27, 1985) cabbage, but negatively affected with Mg content of the outer leaves. 3. Correlations between K and $NO_3-N$ contained in the dry matter of first and second thined, and inner leaves of the harvested cabbage were learnt to be $r;0.9998^{**}$, r;0.4439, and $r;-0.7135^*$ respectively. The higher $NO_3-N$ content in the inner leaves of harvested cabbage was observed at K omitted ammonium nitrate plot where K was deficient, Ca and Mg contents were low. 4. The nutrient absorption and growth of chinese cabbage may take the following process. Nitrate nitrogen increases vegetative growth of the plant with enhanced K uptake and movement in to inner leaves and followed by replacement of Ca uptake and finally Mg uptake and its movement in to inner leaves.

• Korean Journal of Agricultural and Forest Meteorology
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• v.23 no.3
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• pp.163-168
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• 2021

The growth experiment under shading condition has been performed to understand the eco-physiological responses of crops to light in terms of photosynthesis. There are two types of shading: overall shading and partial shading. In this study, the chlorophyll fluorescence of soybean was observed under the overall shading of the box made by polyresin and the partial shading at agrivoltaic system. The overall shading condition during vegetative growth induced lower SPAD and Electron transport rate (ETR). These lower values recovered after removal of shading box. However, the Non-photochemical fluorescence quenching (NPQ) became lower under overall shading and higher under partial shading. Such increase in NPQ limited crop photosynthesis even though the ETR was almost same to the control without shading treatment. Under the condition of partial shading, the values of SP AD and ETR for soybean did not change. However, the NPQ was higher than control condition. This suggests that the crop photosynthesis under both types of shading would be decreased by different eco-physiological processes which are the lower ETR in overall shading and the higher NP Q in partial shading despite the reduced light under shading conditions.