• Journal of Biosystems Engineering
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• v.3 no.1
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• pp.20-36
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• 1978

The effect of binder kicking forces on the shattering losses of paddy rice, which has been widely understood as an outstanding loss factor in harvesting with a binder, were experimentally assessed in this thesis.Through the field tests the optimum time of harvest, in terms of grain moisture contents, was found by considering harvesting losses for two rice varieties, harvested by two different binders, at four or five grain moisture levels.A device was designed and manufactured to apply various kicking forces to the bundles and was used in the bundle kicking tests. It was intended to find out the optimum range of kicking force to minimize the kicking losses. Based on the study, modification of the existing binder kicking mechanism was suggested. The following is a summary of the results of this thesis. 1. In Suweon 258 variety, as the grain moisture content is reduced, so the cutting loss and the kicking loss increase. The grain losses range from 0.77 to 0.82 percent of total field yield for the cutting loss, from 1.83 to 2.01 percent for the kicking loss, and from 2.60 to 2.83 percent for the field loss, when the moisture content is about 22 percent. 2. In Jinheung variety , the field losses increased as the grain moisture content decreased . When the moisture content was 20 percent, the field loss, cutting loss and kicking loss was 0.42-0.49 % , 0.30-0.35, and 0.12 -0.14% of the total field yield, respectively. 3. The difference in the field loss , cutting loss, and kicking loss for the two binders was 0.23% , 0.05% and 0.18% respectively in Suweon 258 variety, and 0.07% , 0.02% and 0.05% respectively ini Jinheung variety. The grain losses for binder B were slightly higher than those for binder A. 4. In the statistical analysis of each variety , the kicking force and the moisture content of the grain, and its interaction were all highly significant at 1% level by T test .The optimum kicking force was found to be in the 3.0-0.4kg range. This does not interrupt the binder operation, while ioses are kept to an acceptale level. 5. To reduce the kicking force of the eXlstmg binder mechanism, the speed of rotation of the kicking arm needs to be redued by increasing the number of driving sprocket teeth, and the position and gear ratio of the knotter-bill and driving bevelgear have to be change to give a !motter-bill speed of 1110 rpm. It is also desirable to attach a belt conveyor which smoothly carries the bundle to the ground. 6. The optimum harvesting time cased on maximum field yield was found to be at a grain moisture content of around 22 percent for Suweon 258 variety, and 20 percent for Jinheung variety. Tota] field yield and field yield at the time amounted to 9, 812.5 kg/ha, 9, 302. 5kg/ha respectively for the Suweon 258, and 7, 819.5 kg/ ha, 7, 158.7 kg/ha respectively for the Jinheung variety.

• Korean Journal of Soil Science and Fertilizer
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• v.23 no.4
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• pp.281-286
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• 1990

Field experiments were conducted to avail the accumulated phosphorus by silica 200kg/10a and compost 2,000kg/10a instead of phosphate fertilization in 1988 to 1989. Cultivated varieties were Dongjinbyeo in paddy soils of Av. $P_2O_5$ 233ppm, and Baegunkong in upland soils of Av. $P_2O_5$ 530ppm. The results were as follows. 1. Available phosphorus in the soil was increased about 60ppm in silica and compost application compared with control. Its increment rate by silica and compost application was higher in paddy soils than in upland soils. 2. Absorbed phosphorus by plant was increased in silica and compost application compared with control, whose difference was higher in soybean plant than in rice plant. 3. Amount of absorbed phosphorus in plant was negative in relation to soil DTPA-Fe, but was positive in relation to soil reduction and root nodule of soybean. 4. Persistence rate of phosphorus was about 80 percent in compost application and 100 percent in phosphate fertilization compared with control, and it was apt to decrease by silica. 5. The yield of rice was no difference between with and without phosphate fertilization, but the yield of soybean was increased 5 percent in none application compared with phosphate fertilization.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.5
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• pp.442-448
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• 1992

In order to determine the critical seeding date in dry paddy field at southern plain area of Gyeongbug province, dry seeds of three different rice cultivars was sown April 25 to June 20 at 15 or 10-day intervals. The number of days from seeding to emergence decreased in late seeding date : from 32 days at April 25 to 7 days at June 10 sowing. The number of seedlings showed 121-154 plants per square meter were not much differed among the varieties and seeding dates. Culm length, panicle length and ripened grain ratio decreased in late seeding date, but number of panicles per square meter, 1,000 grain weight and spikelets number per panicle were similar among the seeding dates. The cumulative effective temperature(mean air temperature-15$^{\circ}C$) from emergence to heading was very constant having 655$\pm$9$^{\circ}C$ in Keomhobyeo, 771$\pm$9$^{\circ}C$ in Donghaebyeo and 801$\pm$3$^{\circ}C$ in Milyang 95, respectively. Grain yield of Dong Haebyeo seeded in June 20 and Milyang 95 seeded in June 10 were much lower compared with other seeding dates and increased green kernel in late seeding date of Donghaebyeo and Milyang 95.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.2
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• pp.104-112
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• 2020

Maize is thought to be an alternative crop to rice in paddy fields for efficient field management and maintenance of rice production at appropriate levels in Korea. Thus efforts to breed waterlogging-tolerant maize cultivars have been ongoing. However, molecular studies related to waterlogging tolerance are limited for developing molecular markers to select waterlogging tolerant maize varieties. In this study, we examined molecular biological changes of B73 in the V3 stage after immersion treatment for 7 days. Overall growth of maize was lower in treated samples compared to non-immersed control samples. The length of leaf and root decreased by 21.3% and 50.6%, respectively and the weight of root reduced by 21.6%. Soil plant analysis development (SPAD) value and chlorophyll content of leaf also decreased by 55.7% and 35.3%, respectively. Reactive oxygen species (ROS) content of root increased by 46.5% at 2 hours in immersion treatment. In addition, immersed roots were 2.5-fold thickened with additional aerenchyma formation in the cortex. In order to identify the causes of these changes, we performed a microarray and found increased expression of genes, such as WIP1, PMIP2, EXPA1, TPS1, and MAS1, in immersed samples. These differentially expressed genes and expression of previously reported genes, including ALDH2, Wusl1032, UP-1, UP-2, and CAT2 were further confirmed with qRT-PCR. Here, we report 7 differentially expressed genes after immersing treatment, which may be utilized as useful resources for breeding waterlogging- tolerant maize.

• Journal of Biosystems Engineering
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• v.6 no.2
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• pp.33-47
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• 1982

To modernize the conventional rice post production technology and reduce grain losses, a transition toward the wet-paddy threshing system has been strongly demanded. The head-feeding type thresher with pneumatic separation has been used dominantly for threshing dried-paddy, but some adverse effects in separation performance for threshing wet-paddy is encounterred. In order to solve the problems, the development of thresher with an additional oscillating sieve to the conventional pneumatic separation has been recommanded. This study was intended to evaluate the separating performance of thresher with oscillating sieve which was attached additionally to the conventional auto-thresher equipped with separation system of blower and suction fan. For different feed rates and rice varieties, wet-and dry-material were tested with threshers attached with and without oscillating sieve. Results of the study are summarized as follows: 1. When the feed rates were 480 and 640 kg/hr, there was no statistically significant difference in power reqirements between the threshers with and without an additional sieve device for both dry-and wet-threshing. However, when the feed rate was 960 kg/hr, power requirements of thresher without sieve were greater for wet-paddy threshing than the thresher with the additional sieve separator by about 20% points. 2. With additional oscillating sieve device, the ratios of total weights of whole grains including grains with branch let and damaged grains to the total output did not show statistical difference among the feed rates. However, with pneumatic separation the ratio was decreased as the level of feed rate increased. 3. The total amount of grains with branchlet (including broken panicle) increased with the moisture content. For both the wet-and dry-material threshing with the additional oscillating sieve, the percent of grains with branchlet to the total output decreased greatly as the feed rate increased. 4. The output of the damaged grains increased as moisture content decreased. Especially, for the dry-paddy threshing, the additional sieve separating device produced more damaged grains than the pneumatic separation at all feed rates. 5. Generally, for dry paddy threshing, the separating performance of the thresher with the additional sieve device was better at all feed rates, showing greater difference with increasing feed rates. 6. Separating losses were greater with the pneumatic than sieve separation for both the wet-and dry-threshing. 7. The overall comparison of separating performance of threshers tested with and without an additional sieve device showed that the former was more effective than the latter for the dry-material threshing. However, for the wet-paddy threshing, the separation performance with a sieve device was better than the pneumatic only when the feed rate was high.

• Applied Biological Chemistry
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• v.31 no.1
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• pp.1-6
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• 1988

The degermed Japonica and J/Indica brown rites were abrasively milled to give an average yield for each milling of about 5% flour, with 85% of the rice left as residual kernel. The contents of protein, fat and ash were in the highest in fraction I and decreased with each successive milling. The fraction I contained twice as much protein as did the original kernel, 5.7 times as much ash and 11.4 times as much fat. However, no significant differences in the distribution among varieties were noticed. Residual kernels contained 68.7% of protein, 5.1% of fat and 41.8% of ash in the original kernel.

• Current Research on Agriculture and Life Sciences
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• v.6
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• pp.25-30
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• 1988

Seven rice varieties and $42F_1$ hybrids of $7{\times}7$ diallel cross were used in genetic analysis for grain size, weight and shape. Effects of average heterosis for grain length and shape showed significantly negative values. GCA, SCA and RCA variances were significant for all characters and also additive variance was more important than dominance variance for grain length, width, thickness and weight. GCA effects of BG 2 and Arborio were highly positive for grain size and weight, and those of BG 2 and Nagdongbyeo were highly negative for grain shape. Partial dominance was observed for all characters. The direction of dominance was negative for grain length, width and shape, and ambidirections for grain thickness and weight. The effective gene number was two for grain length and shape. Both narrow and broad sense heritability were high in all characters.

• Korean Journal of Soil Science and Fertilizer
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• v.9 no.3
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• pp.183-199
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• 1976

1. The cultivated land in Korea has originally low fertility resulting in high dependence to fertilizers. 2. The total fertilizer requirement calculated by the Office of Rural Development (ORD) in 1976 was about 1,153 thousand mts, and the total amount of supply planned by the Ministry of Agriculture and Fishery was 1,010 thoushand mts which is close to the amount calculated by ORD. However, there is some gap between the amount of recommended (N, 11.6; $P_2O_5$: $K_2O$, 7.3kg/10a> and supply planned (N, 12.0; $P_2O_5$, 6.3; $K_2O$. 4.8kg/10a) fertilizers for each elements per unit area 3. For 15 years from 1960 to 1975 the fertilizer consumption of nitrogen was roughly increased from 200,000 mts to 500,000 mts; phosphorus, from 50,000 to 250,000 mts; potassium, from 10, 000 to 170,000 mts; accounting 2.5, 5, and 17 times of increase respectively. 4. The total fertilizer consumption for 5 years from 1967 to 1971 was about 100,000 mts and another 5years from 1971 to 1975 was 300,000 mts indicating three times increase. 5. The direct factors influenced to the increase of fertilizer consumption in recent years are 1) the dissemination of high yielding Tongil type rice varieties which are resistant to heavy fertilization 2) high price policy for agricaltural products 3) increased cultivation of vegetables:, fruits, and forages which require high level of fertilizers. The indirect factors are 1) dissemination of new improved agricultural techniques, 2, improvement of cultivated land conditions through irrigation system and land reform, 3) increased supply of silicate fertilizers, and 4) increase of farm income. 6. The percentage of total fertilizer consumption by rice (32%) and barley (25%) is about 57%. The ratio of total fertilizer consumption by vegetables and forages is expected to increase greatly. 7. Based on the increasing tendency of cultivated land and yield per unit area for last 10 years in each crop, total fertilizer consumptions in 1980, 1990, and 2000 year are estimated to 1,290,000, 1,580,000 and 1,870,000 mts respectively.

• Korean journal of applied entomology
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• v.11 no.2
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• pp.101-107
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• 1972

This experiment was conducted in order to determine the fungi associated with ear blight of rice and their chemical control. 1, Pyricularia oryzes, Helminthosporium oryzne, Epicoccum purpurascens, Curvularia lunata, Cladosporium cladosporoides and Alternaria tenuis et al. were mainly detected in large quantities from the discolored seeds of recommended varieties but Trichoconis padwickii, Fusarium dimerum, and Nigrospora oryzae were mainly detected from Tongil. 2. Pyricularia oryzae, Nigrospora oryzae, and Curvularia lunate et at. were from the necks; Helminthosporium oryzae, Trichoconis padwickii, Stemphylium sp. , Cladosporium cladosporoides, and Alternaria tenuis et at. were from the branches of ear; and Phoma spp. was mainly detected from the kernels. 3. In the laboratory Difolatan WP $0.13\%$ gave good control of Helminthosporium oryzae, Cladosporium cladosporoides, and Alternaria tenuis, et al.; and Dithane M-45 WP $0.2\% gave especially good control of Pyricularia oryzae, Trichoconis padwickii, and Curvularia lunate. 4. In field experiments, the appropriate date of chemical spray was milk ripening stage or panicle emergence stage. Under these conditions Hinosan Ec and Kasugamin Ec were more effective than Difolatan WP and Dithane M-45 WP. However, the assessment of ear blight was complicated by a severe outbreak of neck blast.

• The Korean Journal of Food And Nutrition
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• v.26 no.3
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• pp.601-607
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• 2013

This study was performed to investigate the changes of total and soluble ${\beta}$-glucan contents, purity and physicochemical characteristics of alkali hydrolyzed barley varieties: Saessalbori (SSB), Saechalssalbori (SCSB) and Hinchalssalbori (HCSB). The barleys were hydrolyzed at different concentrations of sodium hydroxide (0.2~1.0 N) for 12 hours. Total ${\beta}$-glucan contents of raw SSB, SCSB and HCSB were 8.40, 7.77 and 8.28%, and soluble ${\beta}$-glucan contents were 4.80, 4.16 and 4.61%, respectively. The total ${\beta}$-glucan contents after alkali hydrolyzed at 1.0 N NaOH were 7.54, 6.89 and 7.54%, also soluble ${\beta}$-glucan contents were 4.82, 4.30 and 4.55%, respectively. The degree of purity of soluble ${\beta}$-glucan in SSB, SCSB, and HCSB were 35.79, 30.91 and 33.90%, respectively. They were increased to 74.02, 75.28 and 81.41% after hydrolyzed at 1.0 N NaOH, respectively. The molecular weight and viscosity of soluble ${\beta}$-glucan solutions were decreased as sodium hydroxide concentration was increased. The re-solubility of raw barley ${\beta}$-glucan was about 50%; however, it was increased to approximately 87% as sodium hydroxide concentration was increased.