• Applied Biological Chemistry
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• v.13 no.2
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• pp.153-170
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• 1970

1. Isolation and identification of amylase-producing bacteria. The powerful strain A-12 and S-8 were respectively isolated from air and soil after screening a large number of amylase-producing bacteria. Their bacterial characteristics have been investigated and it has been found that all characteristics of strain A-12 and S-8 are similar to Bac. subtilis of Bergey's manual except for the acid formation from a few carbohydrates and the citrate utilization, i.e., the strain A-12 shows negative in the citrate utilization, and the acid formation from arabinose and xylose, S-8 shows negative in the acid formation from xylose. 2. Amylase production by Liquid cultures with solid materials. Several conditions for amylase production by strain A-12 in stationary cultures have been studied. The results obtained are as follows. (1) The optimum conditions are:temperature $35^{\circ}C$, initial pH 6.5 to 7.0 and incubation time 3 to 4 days. (2) The amylase production is not affected by the preservation period of the stock cultures. (3) Among the various solid material, the defatted soy bean is found to be the best for t1e amylase production. However, the alkali treatment of the defatted soy bean gives no effect contrary to the cage of defatted rape seed. The addition of soluble starch to the alkali extract of defatted soy bean shows the increased amylase production. (4) Up to 1% addition of ethanol to carbon dificient media gives the improved amylase production, whereas the above effect is not found in the case of carbon rich media. (5) The amylase production can be increased 2.5 times when 10% of defatted soy bean is admixed to cheaply available wheat bran. (6) The excellent effect is found for amylase production when 20% of wheat bran is admixed to defatted dry milk which is a poor medium. The activity is found to be $D^{40^{\circ}}_{30'}$ 7,000(L.S.V. 1,800) in 10% medium. (7) No significant effect is observed due to the addition of various inorganic salts. 3. Amylase production by solid cultures. Several conditions for amylase production by strain A-12 in wheat bran cultures have been studied and the results obtained are as follows. (1) The optimum conditions: are temperature $33^{\circ}C$, incubation lime 2 days, water content added 150 to 175% and the thickness of the medium 1.5cm, The activity is found to be $D^{40^{\circ}}_{30'}$ 36,000(L.S.V. 15,000) (2) No significant effect is found in the case of the additions of various organic and inorganic substances.

• Journal of Sericultural and Entomological Science
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• v.47 no.2
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• pp.68-77
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• 2005

A characteristic of subtropical zones region MK-T2 compares with an gaeryangppong, and the 9-10 schedule the times when a leaf blooms to are fast, and ratio that a branch edge by the colds becomes lean showed 5.7%, and a growth of the new branch which went out delivers 67.2 cm, mulberry loaves of the new branch which went out, and 18.6, a form of a leaf is the 1.10 that length of a leaf grew more a bit than width of a leaf up. Thickness of a leaf is $228.2{\mu}m$, and an area is more similar than gaeryangppong as $225.6cm^2$. in plant taxonomy, the hair whom the style exists short with 0.7 mm, and go to the pistil head inside so as to be rare is distributed, and belong to Dolichostylae Pubescentes. The new branch cutting which executed without remedy processes was independent of a thickness of a case branch, and the form and 100% root was said, and an gaeryangppong compared with the fact that 10% root went out of 15 mm ideal, and was excellent very, and looked, a root went out a root the soil and water, all showed a characteristic to go out at central of a branch bases at 45% ratio. Length was 24.6 mm, and were water rate 78.8%, and mulberry of MK-T2 was carrying together sweetness and acidity to pH 4.7 while, besides, arrival was 19.21 Brix%. A larva period and pupa ratio, cocoon thickness ratio are almost similar to gaeryangppong, or weight of one cocoon, cocoon thickness, 20,002 cocoon quantity shows some results to drop, and be soft of a leaf, and feed value certifications are comparatively top-ranking. As a result of having analyzed amino acid of the 3rd day of 5th silkworm larva which bred to MK-T2, a collation absorbing an gaeryangppong went, and looked, but compared with a collation in case of tests to eat MK-T2, and looked, and the lie collations were not detected a difference at Leu, but MK-T2 tests were detected mutual almost similar amino acid creation. medical efficacy of the 3rd day of 5th silkworm larva ethanol extract which bred to MK-T2 and black results, histologic a case did not appear at HE dyeing about the kidney organization which extracted form the rats which ate a silkworm ethanol extract and dyeing all chemical organization immunity, and one step protein revelation became lower with almost unidentified levels.

• Korean Journal of Agricultural Science
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• v.5 no.2
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• pp.149-157
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• 1978

This study was carried out to obtain basic data for the type selection of furrow openers for the no-tillage soybean planter trailed by the two-wheel tractor from the standpoint of minimum draft and good performance of furrowing. For this study, two models of furrow opener, hoe and disc type, were tested on the artificial soil stuffed in the moving soil bin. The results obtained were as follows. In the case of disc furrow opener, the drafts were measured according to various diameters of discs under the condition of disc angle $8^{\circ}$ and $16^{\circ}$, working depth 3cm and 6cm, working speed 2.75cm/sec. Minimum draft appeared when the diameter of disc was about 28cm and the drafts increased as the diameter of discs became larger or smaller than this diameter. Specific draft showed almost same tendencies as above but showed the minimum when the diameter was about 30cm. For the purpose of controlling the seeding depth, the relationships between draft and working depths, 3cm and 6cm, were tested. The variations of draft concerning the various working depths showed linear changes and were affected in higher degree by depths than other factors. There were general tendencies at both working depths, 3cm and 6cm, that total draft showed the minimum with the disc diameter of about 28cm and specific draft showed it with the disc diameter of about 30cm regardless of disc angle and working speed. For the purpose of controlling the working width and speed, the relationships among drafts, disc angle and working speed were investigated and there were general tendencies that the draft increased as the angle and speed were increased and the draft was affected more by speed than by angle. To compare the hoe-type with disc-type opener, the specific drafts of hoe openers were compared with those of disc opener of $16^{\circ}$ angle and 30cm diameter. The specific draft of disc-type opener with the diameter of 30cm was $0.35{\sim}0.5kg/cm^2$, while $0.71{\sim}1.02kg/cm^2$ in the case of hoe type with the lift angle of $20^{\circ}$ which is 2 times as much as that of disc type in average value. And the furrows opened by disc openers were cleaner than those opened by hoe openers.

• Journal of Korean Society of Forest Science
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• v.10 no.1
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• pp.29-39
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• 1970

Forest fires often destory forests that have taken years to grow in a few minutes. Forest fire therefore, is an important problem in forest management and have caused heavy losses to the nations economy. In order to resolve this problem many investigations have been made in many countries. However, ecological studies on the forest after accidental fire have not yet been made in Korea. In order to conduct such a study, a burned area on Mt. Samak which is located at Dukduwon-ri, Seo-myon, Chunsung-gun, Kangwon-do, was chosen as experimental plot in 1967. The remaining seeds were collected from the burned area, and investigations on their germination rate and their productivity were made comparing to those of the seeds of undemaged area, and following results were obtained. 1. The number of seed collected from the control plots were 740 while it was 537 from the test plots (Table 3, 4). It was considered that this difference between burned and unburned area was mainly due to the fact that some of the seeds had been burnt by the fire, and the unfavorable environmental conditions in the burned area was also considered to be a reason. In the germination rate in the control plots showed 28.1% while it was 3.2% in the test plots. This difference was considered to be due to complete loss of viability of the seed by burning and high heat. 2. In the test plots, sixteen seeds of the Alnus japonica were collected and six of these seeds germinated (index number 100) which was the highest germination rate among the species of collected seeds. From these results, it was considered that a high temperature (above $150^{\circ}C$) caused reduction of the germination rate (Quadrat. 1.2). Seeds of Carex lanceolata var. Nana, were appeared much more in the higher plots than in the lower plots and it seemed to be due to the fact that the forest floor plants were much more abundant in the lower plots than in the higher plots which is covered with shrubbery. And some small seeds midght be able to avoid the effect of fire being burried in the soil or under the gravel. 3. With Pinus densiflora, 43 seeds were collected, and 11 of these germinated in the control plots. However in the test plots, 11 seeds were collected and no seed germinated. This shows that the Pinus densiflora was the weakest in resisting to heat among the observed species in this study. 4. Without exception the germination rate showed a higher index in the herbs than in the woody plants and it is believed that the herbs produced more seed than the wood plants because of the abundance of herbs colony.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.4
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• pp.350-356
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• 2010

This experiment was conducted to select optimum minor cereal crop and variety for the marginal agricultural lands so that they would be used to increase the agricultural land use rate in mountainous areas. This experiment used three different marginal agricultural lands, that is, slope land, barren land and gravelly land. Soil pH of control field was 7.85, slightly alkali, whereas gravelly land showed strong acid(pH 5.1). EC of marginal agricultural lands was generally lower compared to the control, especially barren land showed 0.05dS $m^{-1}$ which was the lowest among marginal agricultural lands. Foxtail millet showed no significant difference of heading and ripening date among marginal agricultural lands. Foxtail millet of slope land showed the highest culm length(169.5 cm) and grains per ear(4913.9 grains) among marginal agricultural lands except control field. Growth duration of three varieties was varied from 112 to 113days, which was not different statistically. In grains per ear of common millet, slope land showed 787.1 grains which was the highest among marginal agricultural lands except control field. Among varieties, Byorukgijang showed the highest grains per ear(827.2 g/ear), whereas 1000 grain weight was 5.5 g which was lower compared to that of Hwanggijang(6.2 g). In sorghum, slope land showed the highest grains(2563.8 grains) per ear and ears per 3.3 $m^2$(26.0 ears) except control field. Growth duration of three sorghum varieties almost the same from 122 to 123 days, whereas the highest grains per ear was obtained from Moktaksusu(2357.6 grains). Jangmoksusu showed the highest 1000 grain weight(23.8 g) among three sorghum varieties. In yield of three foxtail millets, the highest yield was obtained from slope land(282.0 kg/10a) among marginal agricultural lands and Mongdangjo showed the highest yield(252.3 kg/10a) among three varieties. In yield of three common millets, the highest yield was obtained from slope land(196.0 kg/10a) among marginal agricultural lands and Byorukgijang showed the highest yield(173.8 kg/10a) in three varieties. In three sorghum varieties, the highest yield was obtained from slope land(301.7 kg/10a) among marginal agricultural lands and Moktaksusu showed the highest yield(236.5 kg/10a) among three varieties.

• Korean Journal of Organic Agriculture
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• v.17 no.3
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• pp.371-380
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• 2009

This study was conducted to assess effects of supplying different types of nitrogen sources as fertilizers on productivity and feed values of barley and rye as winter forage crops, and ultimately done to get good quality of organic forages with higher fertilization of soil. For barley, N+P+K plots were significantly (P<0.05) higher in annual dry matter (DM) and total digestible nutrients (TDN) yields than other plots. However, cattle manure plots had significantly (P<0.05) higher annual DM and TDN than P+K and non-fertilizer plots. Plots of 50%-cattle manure and mixed sowing with hairy vetch or forage pea were higher than only 50%-cattle manure plot, particularly, these were significantly higher than non-fertilizer, and their crude protein (CP) yields were much higher than other plots. Crude protein contents were significantly higher in N+P+K and 50%-cattle manure slurry plots than non-fertilizer and P+K plots, and plots of mixed sowing with hairy vetch or forage pea in application of 50%-cattle manure had higher CP content than other plots. ADF content was lowest in 50%-cattle manure+forage pea plots, but highest in 100%-cattle manure plots. NDF content was lowest in legumes-mixed sowing, but highest in 100%-cattle manure plots. TDN content was the highest in forage pea plots, and plots of 50%-cattle manure and legumes-mixed sowing had high RFV, but cattle manure plots rich in ADF and NDF content had the lowest TDN and RFV. For rye, plots of 50%-cattle manure+hairy vetch mixed sowing, and N+P+K application had significantly higher annual DM, CP and TDN than other plots except for cattle manure. DM productive efficiency to nitrogen fertilization was markedly higher for cattle manure plots than for chemical fertilizer. This tendency was more conspicuous in plots of 50% cattle manure+legumes-mixed sowing. CP content was higher for N+P+K plot than for all plots, and plots of 50%-cattle manure + legumes-mixed sowing were significantly higher than other plots. On the contrary, forage pea-mixed sowing plot had the lowest ADF and NDF, but TDN and RFV were significantly (P<0.05) higher than other plots. Grass crop cultivation together with legumes by applying livestock manure to soil may lead to higher palatability of livestock, and better quality of forage. Furthermore, cattle manure application increased production yield per ha and CP contents. Thus, when applying forage crops produced by cattle manure application and mixed sowing to organic livestock production, it was conceived that forages produced might become a substitute for foreign organic grain as protein sources.

• Korean Journal of Organic Agriculture
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• v.21 no.3
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• pp.451-465
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• 2013

This study was conducted to estimate Hanwoo carrying capacity when whole crop barley, rye, wheat and tritcale as winter forage crops was grown on different applying sources (chemical fertilizer, cattle or organic fertilizer) and mixed sowing combination with hairy vetch or forage pea during the period of 2011~2012. The experimental plots within whole crop barley or rye were consisted of 7 treatments, which were non-fertilizer, chemical fertilizer (P+K), chemical fertilizer (N+P+K), organic fertilizer, cattle slurry, cattle slurry with hairy vetch, and cattle slurry with forage pea. Each plot was triplicates and experimental treatments were allocated in the randomized complete block design. For whole crop barley, annual mean dry matter (DM) and total digestible nutrients (TDN) yields were the highest in N+P+K plots, but there were no significant differences among organic fertilizer, cattle slurry and mixed sowing with legumes. The TDN were the highest in mixed sowing plots of forage pea plus cattle slurry application. As 450 kg Hanwoo heifers were fed diets included 70% whole crop barley, organic fertilizer, cattle slurry application and mixed sowing plots of forage pea is capable of raising average 2.8 to 3.1 heads/ha a year. For whole crop rye, annual mean DM were the highest in N+P+K plots, but there were no significant differences among cattle slurry. Organic fertilizer application significantly increased TDN and relative feed value (RFV) in comparison with treatments of N+P+K fertilization as chemical fertilizers. In case of 450 kg Hanwoo heifers fed diets included 70% forage rye, it is estimated that cattle slurry application (mixed sowing with legumes) plots can rear average 2.8~ 3.2 heads/ha a year. For whole crop wheat, annual DM, crude protein, and TDN yields of application groups and mixed sowing treatment with legumes showed 6.90~7.44, 0.53~0.60 and 4.35~5.04 ton/ha, respectively. In case of 450 kg Hanwoo heifers fed diets included 70% forage rye, it is estimated that cattle slurry application (mixed sowing with legumes) plots can rear average 3.1~3.7 heads/ha a year. For Triticale, TDN yield was significantly (P<0.05) higher N+P+K plots, organic ferilizer, cattle slurry, cattle slurry with legumes than for no fertilizer and N+P+K plots. The Crude protein (CP) contents were the highest in mixed sowing plots of forage pea plus cattle slurry application. In case of 450 kg Hanwoo heifers fed diets included 70% forage triticale, it is estimated that cattle slurry application (mixed sowing with legumes) plots can rear average 3.4~3.7 heads/ha a year. It can be concluded that, on the basis of DM yield, not only mixed sowing with legumes by applying cattle slurry rather than single sowing of whole crop barley or whole crop rye enhanced production yield and feed values, but also it could be a substitute for imported grains as dietary protein sources in the case of feeding Hanwoo.

• Korean Journal of Organic Agriculture
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• v.16 no.4
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• pp.421-434
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• 2008

This study was carried out to estimate the selection of appropriate forage crops, proper application levels of livestock manure, and carrying capacity per unit area for organic livestock, as influenced by livestock manure application levels compared with chemical fertilizer to corn and sorghum $\times$ sorghum hybrid, in order to produce organic forages by utilizing livestock manure. For both corns and sorghum $\times$ sorghum hybrids, no fertilizer plots had significantly (p<0.05) lower annual dry matter (DM), crude protein (CP) and total digestible nutrients (TDN) yields than those of other plots, whereas the N+P+K plots ranked the highest yields, followed by 150% cattle manure plots and 100% cattle manure plots. Dry matter, CP and TDN yields of cattle manure plots were significantly (p<0.05) higher than those of no fertilizer and P+K plots. In applying cattle manure, the yields of cattle slurry plots tended to be a little higher than those of composted cattle manure plots. Assuming that corns and sorghum $\times$ sorghum hybrids produced from this trial were fed at 70% level to 450kg of Hanwoo heifer with 400g of average daily gain, livestock carrying capacity (head/year/ha) ranked the highest in N+P+K plots of the case of corns (mean 6.7 heads), followed by 150% cattle slurry plots (mean 5.6 heads), 150% composted cattle manure plots (mean 4.8 heads), 100% cattle slurry plots (mean 4.4 heads), 100% composted cattle manure plots (mean 4.3 heads), P+K plots (mean 4.1 heads), and no fertilizer plots (mean 3.1 heads). Meanwhile, in case of sorghum $\times$ sorghum hybrids, N+P+K plots (mean 5.7 heads) ranked the highest carrying capacity, followed by $100{\sim}150%$ cattle slurry plots (mean $4.8{\sim}5.2$ heads), 150% composted cattle manure plots (mean 4.7 heads), 100 % composted cattle manure plots (mean 4.3 heads), P+K plots (mean 3.8 heads), and no fertilizer plots (mean 3.4 heads). The results indicated that replacing chemical fertilizer by livestock manure application to cultivation soil for forage crops could enhance not only DM and TDN yields, but also organic stock carrying capacity. In conclusion, it was conceived that organic forage production by reutilizing livestock manure might contribute to reduced environmental pollution and the production of environment friendly agricultural products through resources recycling.

• Korean journal of applied entomology
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• v.44 no.1 s.138
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• pp.21-30
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• 2005

Feeding behavior of foraging ants including visiting numbers, species, and preference on insect cadavers killed by entomopathogenic nematodes <(Heterorhabditis sp. KCTC 0991BP (He) and Steinernema carpocapsae KCTC 0981BP (Sc)> and their symbiotic bacteria was investigated in Dongrae Benest Golf Club, Anyang Benest Golf Club, Gapyung Benest Golf Club and Ulsan Golf Club. The number of ants, kinds and numbers of cadavers taken away by ants were different depending on killing method, golf club and site within the golf courses (fairway and rough). The feeding preference of ants was the lowest on cadavers killed by He. At Dongrae Benest Golf Club Lasius japonicu ($75{\pm}5\%$) and Monomorium floricola ($10\%$) took away cadavers only at the rough. The visiting rate of ants was $85{\pm}6\%$ at the rough, but none at the fairway by 16 hours. The taken rate of cadavers by ants was the lowest on He-killed cadavers representing $16.7\%$ compared with $40.0\%$ on Sc-killed cadavers, $53.3\%$ on fenitrithion-killed cadavers, and $56.7\%$ on natural dead cadavers by 12 hours. At the rough of hole 6 in Anyang Benest Golf Club, Tetramorium tsushimae ($33{\pm}12\%$), Pheidole fervida ($17{\pm}15\%$), Camponatus japonicus ($10\%$), Formica japonica ($7{\pm}6\%$), Paratrechina flavipes ($3{\pm}6\%$), and Crematogaster matsumurai ($3{\pm}6\%$) took away cadavers, but $23{\pm}15\%$ of cadavers were not visited by ants. Ants took away $40\%$ of Sc-killed cadavers, $16.7\%$ of frozen-killed cadavers, and $3.4\%$ of He-killed cadavers. The number of visiting ants was low at the hole 9 of Cherry course in Gapyung Benest Golf Club and only Tetramorium tsuhimae and Paratrechina flavipes were found from one site. The density of entomopathogenic nematodes did not influence ant visiting on cadavers, but burying affected ant visiting. Although ants took away unburied cadavers, buried cadavers were taken away at the hole 6 of Dongrae Benest Golf Club by 16 hours. Ant visiting had the same tendency on symbiotic bacterium-treated biscuit as nematode-killed cadavers. The visiting was less on biscuit inoculated by Photorhabdus sp., a symbiotic bacterium of He than on biscuit inoculated by Xenorhabdus nematophila, a symbiotic bacterium of Sc.

• Korean Journal of Agricultural Science
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• v.3 no.1
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• pp.95-104
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• 1976

This study was conducted to test the harvesting operation of two kinds of rice varieties such as Milyang #15 and Tong-il with a imported two furrow Japanese combine and was performed to find out the operational accuracy of it, the adaptability of this machine, and the feasibility of supplying this machine to rural area in Korea. The results obtained in this study are summarized as follows; 1. The harvesting test of the Milyang #15 was carried out 5 times from the optimum harvesting operation was good regardless of its maturity. The field grain loss ratio and the rate of unthreshed paddy were all about 1 percent. 2. The field grain loss of Tong-il harvested was increased from 5.13% to 10.34% along its maturity as shown in Fig 1. In considering this, it was needed that the combine mechanism should be improved mechanically for harvesting of Tong-il rice variety. 3. The rate of unthreshed paddy of Tong-il rice variety of which stem was short was average 1.6 percent, because the sample combine used in this study was developed on basisof the long stem variety in Japan, therefore some ears owing to the uneven stem of Tong-il rice could nat reach the teeth of the threshing drum. 4. The cracking rates of brown rice depending mostly upon the revolution speed of the threshing drum(240-350 rpm) in harvesting of Tong-il and Milyang #15 were all below 1 percent, and there was no significance between two varieties. 5. Since the ears of Tong-il rice variety covered with its leaves, a lots of trashes was produced, especially when threshed in raw materials, and the cleaning and the trashout mechanisms were clogged with those trashes very often, and so these two mechanisms were needed for being improved. 6. The sample combine of which track pressure was $0.19kg/cm^2$ could drive on the soft ground of which sinking was even 25cm as shown in Fig 3. But in considering the reaping height adjustment, 5cm sinking may be afford to drive the combine on the irregular sinking level ground without any readjustment of the resaping height. 7. The harvesting expenses per ha. by the sample combine of which annual coverage area is 4.7 ha. under conditions that the yearly workable days is 40, percentage of days being good for harvesting operation is 60%, field efficiency is 56%, working speed is 0.273m/sec, and daily workable hours is 8 hrs is reasonable to spread this combine to rural area in Korea, comparing to the expenses by the conventional harvesting expenses, if mechanical improvement is supplemented so as to harvest Tong-il rice. 8. In order to harvest Tong-il rice, the two furrow combine should be needed some mechanical improvements that divider can control not to touch ears of paddy, the space between the feeding chain and the thrshing drum is reduced, trash treatment apparatus must be improved, fore and rear adjust-interval is enlarged, and width of track must be enlarged so as to drive on the soft ground.