• Applied Biological Chemistry
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• v.14 no.3
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• pp.183-189
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• 1971

The studies reported herein were conducted to inquire the effect of fused siliceous materials which mixed with sand and quartz added calcium fertilzer on rice grown on low available silica content soil. The applied nitrogen level were examined for the two plots, nitrogen 10kg and 20kg per 10 a., and the siliceous materials(Wollastonite, Fused sand and Fused quartz) were applied as levels to 100kg, 300kg and 500kg per 10a. in the pots. The results are summerized as follows; 1. The available silica content solved in N/2 HCl solution of fused sand was more than of fused quartz but the silica solubility in 2% citric acid of fused quartz were higher than other. 2. The absorbed silica content by plant grown on the fused quartz plot was the highest among other siliceous materials and of fused sand and natural wollastonite were at almost equal. The ratio of absorbed silica of natural wollastonite was highest among them and in fused materials, the quartz was higher than sand. 3. The productivity of rice was increased by percentage of filled grain, weights of 1000 grains, and number of spikelets on account of the large quantity of the silica absorbed by plant Especially fused quartz showed the highest productive effect among siliceous materials and natural wollastonite and fused sand were similar effect. 4. From the above results. the fused quartz was selected as expelled siliceous fertilizer on rice plant among them and the fused sand was equal effect to natural wollastonite.

• Journal of the Korean Wood Science and Technology
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• v.12 no.4
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• pp.31-35
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• 1984

These experiments were carried out to investigate anatomical properties of Forsythia in Korea. The results obtained were summarized as follows: It was estimated that the vessel of cross section was almost simple pore and multiple pores which were compounded two or three units were showed sometimes and arrangement of vessel were ring porous wood. In the mean length of vessel, Forsythia koreana was ranged $539.98{\pm}154.71{\mu}$ and Forsythia ovata $602.22{\pm}157.38{\mu}$ and Forsythia nakaii T. Lee $465.50{\pm}83.02{\mu}$. In the mean length of fiber wood, Forsythia koreana $387.40{\pm}68.23{\mu}$, and Forsythia ovata was $533.90{\pm}106.77{\mu}$ and Forsythia nakaii T. Lee was $482.40{\pm}72.33{\mu}$. The type of Ray parenchyma was heterogeneous ray I tissue. The mean length of procumbent ray cell in the radial section was $42.14{\pm}8.30{\mu}$ and that of rectangle type in up right ray cell was $45.76{\pm}7.19{\mu}$ and that of square type was $26.66{\pm}2.99{\mu}$. The mean height of ray parenchyma in the tangential section was $174.80{\pm}37.51{\mu}$ and the width of ray parenchyma was $17.25{\pm}3.59{\mu}$ and the mean number of ray parenchyma was $14{\pm}3$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.1
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• pp.55-61
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• 1984

A Korean local maize line, MET, which has multi-ears and tillers has been proved as a potential source for silage production. However, no fundamental genetic nature for the line has been investigated. Therefore, this study was done to find genetic information on the multi-earing and -tillering habits of MET line. MET line and a hybrid. (Mo 17 ${\times}$ B68), with monoculm and single ear per plant were used for production of F$_1$(F$\_$1-12/ and F$\_$1-21/), F$\_$2-12/, F$\_$2-21/, BC$\_$1-12/ and BC$\_$1-21/ generations. From the comparison of reciprocal crosses, it was found that the tillering and earing habits of the MET line are controlled by cytoplasmic factors. The tiller and ear numbers, and barren ears were all characters associated with the MET cytoplasm. The cytoplasmic effect of MET on tiller and ear numb en was not evident in F$_1$ generation, probably because of suppressing effect of heterosis on appearance of tillers or ears. Genetic parameters for the gene action for both tiller and ear number also indicated a lack of mono- or digenic-chromosomal gene effects. The heritability (broad) was very low for both characters. Therefore, it is strongly concluded that the tillering and earing characters of MET line are due to cytoplasmic reasons.

• Journal of Environmental Impact Assessment
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• v.15 no.1
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• pp.53-65
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• 2006

Topographic condition is one of the most important things in farming activities. The topographic condition didn't matter for farming in the past because agricultural products had competitive power in the market. So farmers tried to extend their farms without any concern of topographic condition. We need less labor-consuming farming as industrial structure has been changed and the competitive power of the farming has been getting weak. This study analyzed the fallow potential in agricultural area by topographic condition so that we have got results as follows. Maps of elevation, slope, distance from roads and water resources were made for getting a fallow probability model in farms, and these 4 factors were used as independent variables while a variable on whether it is fallow or not is a dependent variable in logistic regression model. In an analysis of the fallow potential depending on farm land types, the fallow probability in fallow orchard showed the highest value of farm lands, 0.973. Cultivated orchard had 0.730 and upland had 0.616 of the fallow probability. The fields having high fallow potential had high elevation, steep slope, and long distance from water resources and roads. Especially, fields having a probability over 0.99 appeared in orchards, fallow uplands and single cropping uplands, which were recognized to have several disadvantages related to the fallow like as high elevation, steep slope, and long distance from water resources and roads. With the logistic analysis, the suitable farm lands appeared at 16.45m of the mean elevation, 1.89 degree of the mean slope, 39.91m of the average distance from water resources, and 32.39m of the average distance from roads. On the contrary, non-suitable land appeared at 114.7m of the mean elevation, 24.9 degree of the mean slope. The distance from roads was more important variable than the distance from water resources for analyzing suitable farm land.

• Journal of Environmental Impact Assessment
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• v.15 no.1
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• pp.1-12
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• 2006

Changes in the soil physical property and the topographic condition derived from agricultural activities like as farming activities, land clearance and cutting down resulted in environmental and economic problems including the outflow of nutrient from farms and the water pollution. Several theories on the soil conservation have been developed and reviewed to protect soil erosion in the regions having a high risk of erosion. This study was done using the USLE model developed by Wischmeier and Smith (1978), and model for the slope length and steepness made by Desmet and Govers (1996), and Nearing (1997) to evaluate the potential of the soil erodibility. Therefore, several results were obtained as follows. First, factors affecting the soil erosion based on the USLE could be extracted to examine the erosion potential in farms. Soil erodibility (K), slope length (L), and slope steepness (S) were used as main factors in the USLE in consideration of the soil, not by the land use or land cover. Second, the soil erodibility increased in paddy soils where it is low in soil content, and the very fine sandy loam exists. Analysis of the slope length showed that the value of a flat ground was 1, and the maximum value was 9.17 appearing on the steep mountain. Soil erodibility showed positive relationship to a slope. Third, the potential soil erodibility index (PSEI) showed that it is high in the PSEI of the areas of steep upland and orchard on the slope of mountainous region around Dokjigol mountain, Dunji mountain, and Deummit mountain. And the PSEI in the same land cover was different depending on the slope rather than on the physical properties in soil. Forth, the analysis of land suitability in soil erosion explained that study area had 3,672.35ha showing the suitable land, 390.88ha for the proper land, and 216.54ha for the unsuitable land. For unsuitable land, 8.71ha and 6.29ha were shown in fallow uplands and single cropping uplands, respectively.

• Applied Biological Chemistry
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• v.20 no.1
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• pp.109-116
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• 1977

Much attention has been paid to the fact that quite a few herbicides such as phenylcarbamates, phenylureas, and acylanilides form azo compounds known as carcinogens by virtue of the microoranisms in soil. In consequence, many investigators synthesized. TCAB, an azo compound, starting from 3,4-dichloronitrobenzene for the related studies. However, the authors were under the necessity of synthesizing $^{14}C-ring-labeled$ TCAB from $^{14}C-ring-labeled$ 3,4-DCA available, in addition to making up for the disadvantage of dechlorination in the reduction of 3,4-dichloronitrobenzene. The new method is as follows:TCAB, $^{14}C-ring-labeled$ and non-labeled, was produced by aerial oxidation of 3,4-DCA catalyzed by CuCl with pyridine as solvent at $60^{\circ}C$ for 5-12 hrs, giving 80.2% yield. The procedure forpurification was described in detail. The identities of TCAB isomers were confirmed by means of autoradiography, TLC, GLC, IR, and MS.

• Korean Journal of Agricultural Science
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• v.4 no.1
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• pp.66-74
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• 1977

To investigate the condition of infectious rate of fascioliasis in the farm animals. This survey was carried out, by the interdermal reaction from different animals, ages and pestures in Daejeon Suburbs and Cattle market and Abattoir. The average positive rate of infectious reaction were 31.0% in Korean Cattle, 38,7% in dairy Cattle, 33.8% in Korea native Goats and 26.9% in dairy Goat. The positive rate was higher at the age of 2~6 that compares with at age of yearling. From survey on the river side area, valley and wet area, the rate of positive was occured higher, than from plain, high land and in case of animals have not been grazing. And the detective rate of liver fluke among the positive reaction was occured 92.5% in Korean Cattle and 94.7% in Korea native Goat.

• Korean Journal of Agricultural Science
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• v.4 no.1
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• pp.43-50
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• 1977

This stuy was conducted to analyse the variation in occurrance of fruit body of Agaricus bisporus (Lange) Sing, depending on difference of cultivation and harvesting method and to find out a method for early predicting the mushroom yield potential at the base of results of the analysis. The results obtained were as follows ; 1. Total mushroom yield was highly correlated with picking amount of fruit bodies during first 30 days of picking period, and yield potentiality in the certain high yielding mushroom house was markedly affected with the yield of middle and late period of picking. 2. Variation of mushroom yield with varying the degree of maturity of fruit bodies appeared to be different between spring and autumn cropping : in case autumn cropping was usally undertaken with normal cropping scheme, mushroom yield showed a reduction in early period of picking but an increase in late period when the mushrooms where picked at pre-matured stage. 3. When the picking rate of button form was laid in the range of 20~45%, and increase of total mushroom yield was accompanied by an increasing tendency of picking rate of button form. 4. Cropping results from mushroom houses could be early predicted from the regression equations, which was based on the analysis of variation in fruit body occurance throughout the picking period.

• Korean Journal of Agricultural Science
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• v.4 no.1
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• pp.105-111
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• 1977

Inhibitory effect of sugars on lipase production by Trichosporon cutaneum was observed in the previous study (Kim, 1972), and inhibition was distinctive by the addition of glucose, fructose, mannose, xylose and arabinose to the soybean meal medium among various carbon sources. These experiments were carried out to study the effect of sugars on cell growth and lipase production by the strain using the soybean extracts liquid medium under a shaking culture system. Changes in color and pH of the medium were caused by heat sterilization when various sugars were added. To elucidate the possible effect of these coloring matters on lipase production and cell growth: changes in pH of the culture, cell concentration and level of the enzyme activities were determined when the culture was grown for 48 hours at $30^{\circ}C$ on a reciprocal shaker. The results obtained were as follows: 1. Density of brownish color which formed during heat sterilization was varied with the variety of sugar used, ie, strong in pentose such as xylose: weak in hexose such as galactose, mannose, glucose: very weak in disaccharide such as maltose, sucrose. When the color density was stronger, decrease in pH after sterilization was marked. 2. Cell growth and lipase production was not so effect by the coloring matters as by sugars. 3. The more the cell mass of the culture, the lower the level of lipase production in the culture supernatant. 4. Among the sugars which caused the distinctive inhibition of lipase production, a slight relief of inhibition was noticed by the addition of xylose, whereas the cell growth was repressed. 5. When cell growth was better, decrease in pH of the medium was greater during cultivation.

• Journal of Korean Society of Forest Science
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• v.1 no.1
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• pp.12-21
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• 1962

Outdoor cuttings studies on two coniferous species, pitch pine and needle fir, have been made at Suwon, Korea extending from March to early May, 1956. The purpose of these studies was to find the effects of ages of parent trees, topophysis, dilute hormone solution treatments and the time at which the cuttings were collected on the rooting response of the cuttings. On September 2, rooting results were examined. Pitch Pine (Pinus rigida) The total of 1335 cuttings were collected from 3- and 10-year old trees. The cuttings treated were planted on March 13 and April 20. 1. In the cuttings collected from 3-year-old seedlings, the best result (34 percent rooted) was obtained by treating ends of cuttings with a mixture of 50 ppm IBA and 50 ppm NAA. 2. No rooting was observed in lammas shoots. 3. The cuttings from 3-year-old seedlings gave better rooting than those from 10-year-old trees. 4. The root origins were developed from the lower part of the cutting and the cut surface. Needle fir (Abies holophylla) One hundred twenty-five cuttings were collected from a 30-year-old tree. The cuttings treated with any one of four mixed hormone solutions were planted on March 23. 1. Fifteen cuttings out of 75 cuttings from the lower half of the crown were rooted. The cuttings obtained from the upper half of the crown did not root at all. 2. The cuttings treated by the hormone solution made up of 20 ppm IAA, 20 ppm IBA, 20 ppm NAA, 20 ppm thiamine and 5 percent sucrose gave the best rooting (22 percent). 3. All roots originated from callus tissues and irregularly arranged parenchymatous tissues near the cut base.