• Journal of Photoscience
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• v.11 no.1
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• pp.25-28
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• 2004

The kinetics of the loss of leaf fresh weight during incubation of barley and rice leaves in 9% or 15% NaCl solutions were biphasic, indicating the existence of a controlling mechanism for water transport. The first rapid phases reached their plateaus within 1 and 2 h in the case of rice and barley leaves, respectively. When barley leaves were fed with sodium fluoride, an inhibitor of phosphatase inhibitor, through their epicotyls for 3 h in darkness, prior to the treatment of NaCl, the biphasic pattern shown during NaCl treatment was disappeared resulting in linear decreases in the relative fresh weights. The results suggest that NaF accelerates salt-induced water efflux from plant cells, possibly by inhibiting the protection mechanism that may act in NaF-untreated leaves. The linear water loss can be explained in terms of phosphorylation of aquaporin by blocking its dephosphorylation in the presence of the phosphatase inhibitor to keep aquaporin in a phosphorylated form. However, the effect of NaF shown in barley leaves were not observed in rice. These results suggest that the regulation of water transport depends on plant species, and the mechanism for the controlling water transport in rice is different from that of barley.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.1
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• pp.14-22
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• 1989

Rice varieties showing different degree of resistance were compared with their yield losses due to the damage of sheath blight disease in field condition through 1985 to 1986. Gayabyeo showed the lowest value of disease severity among 5 varieties tested in 1985 and 8 in 1986. and Taebaekbyeo, Kwanakbyeo and Labelle showed higher value of disease severity under the condition of artificial or natural disease inoculation. Grain yield of Gayabyeo, a moderate resistant rice variety, was reduced by 0.3 to 5％ in the rate due to sheath blight disease damage and Taebaekbyeo. a susceptible variety. showed the highest in the rate of yield loss, 6.8 to 25.8 ％. The matured grain rate and 1000-grain weight of the matured tiller were decreased when the developing disease lesion reached to the flag leaf, and then panicle weight was decreased more than 25 ％ compared with panicle of healthy culm. In conclusion, Gayabyeo showed the lower rate of yield loss because of slow development of disease to the upper leaves after initial disease occurence on the lower parts of rice plants.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2011.10a
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• pp.335-343
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• 2011

We examined the effect of the acidic liquid from carbonized rice hull(ALCRH) treatments to molded fiber packages(MFP) on weight, Haugh unit, pH and microbial activity of egg to extend the shelf life in egg packaging. Higher concentration and surface spray treatment of the acidic liquid extended the shelf life of egg. ALCRH treatment to MFP improved the performance of the packaging for egg in terms of decreased weight loss and retarded microorganism growth of eggs during storage.

• Korean Journal of Weed Science
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• v.18 no.1
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• pp.12-19
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• 1998

The pattern of rice cultivation in Korea is changing from hand transplanting and machine transplanting into direct-seeding for low input and cost-down practices. However, there are still some obstacles to establish the direct-seeding cultural practices because of poor seedling stand, lodging, and weed infestation. In particular, there were much more and wide weed occurrence in direct-seeding rice as compared with the transplanted rice. Weed occurrence in terms of dry weight of weeds was highest in dry direct-seeded rice followed by sowing an puddled soil, sowing on submerged soil in order as compared with transplanting with infant rice seedling. Echinochloa crux-galli was a common dominant weed with 35~44% distribution in any direct-seeding methods. The dominant weed species were E. crux-galli, Cyperus difformis, C. serotinus, and Ludwigia prostrata in dry-seeded rice. The dominant weed species in water-seeded rice were E. crus-galli, Eleocharis kuroguwai, Scirpus juncoides, and Monochoria vaginalis. Yield loss of rice due to weeds at weedy condition was 96% in dry direct-seeded rice. In water-seeded rice, yield loss was 61%, whereas yield loss was 40% in machine transplanting with infant rice seedling.

• Journal of environmental and Sanitary engineering
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• v.14 no.4
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• pp.93-98
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• 1999

We had investigated combustion properties of rice bran dusts. Decomposition of rice bran dusts with temperature were investigated using DSC and the weight loss according to temperature using TGA in order to find the thermal hazard of rice bran dusts, and the properties of dust explosion in variation of their dust with the same particle size. Using Hartman's dust explosion apparatus which estimate dust explosion by electric ignition after making dust disperse by compressed air, dust explosion experiments have been conducted by varying concentration and size of rice bran dust.According to the results for thermodynamic stability of rice bran dust, there are little change of initiation temperature of heat generation and heating value for used particle size. But initiation temperature of heat generation decreased with high heating rate whereas decomposition heat increased with particle size. Average maximum explosion pressure was $10kgf/cm^2$ for 60/70 mesh and $1.5mg/cm^2$ dust concentration.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.288-288
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• 2022

Rice is an important staple in the world. And drought is one of the important constraints that negatively affect yield loss and grain quality of rice. CRISPR/Cas9 is a new breeding strategy that can improve the characteristics of rice quickly and accurately. CRISPR/Cas9 is a novel approach that can reliably harvest rice yields in response to a rapidly changing climate. In addition, there is no externally inserted DNA left in genome-editing rice, and it is receiving attention as being able to take responsibility for future food because its characteristics are continuously improved. In the future, high levels of drought resistant in water-constrained environments will be required, which will reduce yield loss. OsSAP was genome-editing with CRISPR/Cas9 in rice. A different line number was assigned to each panicle, and the generation advanced by applying the ear-to-row method. Genome-editing rice has improved drought resistance in drought conditions. Also, in genome-editing rice, the target sequence was homozygous in the 0 generation, and the coefficient of variation of heading date, number of tiller, and 1,000-grain weight was very small in 2 generation. In the era of rapidly changing climate change, CRISPR/Cas9 presents a new breeding strategy that can rapidly and accurately improve agronomic traits of major food crops as well as rice. CRISPR/Cas9 is applied together with traditional breeding to develop into a new breeding strategy, it is suggested that food can be obtained stably in response to climate change.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.1
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• pp.22-27
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• 2005

To find out the optimum mixture ratio of ammonium and nitrate on rice plant, 4 rice varieties were examined during 14days after transplanting in hydroponics with the different ratio of ammonium to nitrate(100 : 0, 75: 25,50: 50, 25: 75 and 0: 100). The highest N uptake from solution and the maximum plant dry weight were $60\~70\%$ ammonium and $30\~40\%$ nitrate mixture treatment both in Japonica and Tongil type rice plants. And with the same varieties N-uptake and N use-efficiency were compared between 10.0 mM and 1.0 mM nitrogen using $70\%$ ammonium and $30\%$ nitrate for 24 days after transplanting. Rice plants absorbed more nitrogen$(131\~145\%)$ in 10.0mM than 1.0mM treatment but accumulated N in rice plants were almost the same in both treatment. Among the tested rice cultivars, dry matter production and total accumulative nitrogen in rice plants were much high in Tongil type than japonica type rice cultivars. N-recovery ratios of rice plants from uptake N were $90.8-99.0\%$ in low concentration N solution(1.0 mM), but $69.4-81.7\%$ were observed in high concentration N solution(10.0 mM). It means that suppling low concentration N steadily will be better to prevent loss of N without reducing of growth in rice plants.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.2
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• pp.132-136
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• 2002

The rice straw managements are essential for maintaining soil fertility as well as reducing chemical fertilizer application in paddy field. A field experiment was conducted on moderately well draining alluvial paddy soil to investigate the decomposition pattern of rice straw. The mesh bags containing the rice straw harvested in the previous year were placed at soil surface and buried into around 10cm depth and recovered periodically for determining the straw decomposition. Pot experiments were conducted to investigate the fates of N released from $^{15}$ N-labeled rice straw under different levels of N fertilizer application. The overall decomposition patterns of rice straw were similar for the two incorporation depths in transplanted paddy field. The straw incorporated at transplanting date showed weight loss of about 50%, 70% and 90% after 2 months, 5 months, and 2 years, respectively. The decompositions of straw cell wall components showed somewhat different pattern. The decompositions of cellulose and silica were similar to that of dry weight while the decomposition of lignin was slower than that of cellulose and silica. N was released from rice straw 42% and 65 % of the initial N after one month and after five months, respectively. P release was faster than N release. Recoveries of rice straw-$^{15}$ N by rice plants were 10.2, 13.4 and 14.9% in 0, 120 and 240 mg N pot$^{-1}$ , respectively. Soil recoveries of rice straw $^{15}$ N were 17.3, 20.6 and 18.9% in 0, 120 and 240mg N pot$^{-1}$ , respectively.

• The Journal of Internal Korean Medicine
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• v.27 no.4
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• pp.836-844
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• 2006

Background: Mahuang (Ephedra sinica STAPF) is well known as an herbal medicine and has been widely used to reduce body weight and increase athletic ability. However, as a result of reporting many cases of adverse effects on the cardiovascular system, use of dietary supplements containing ephedra was prohibited by the FDA. Objectives : The object of this study was to find the effectiveness of ephedra on weight loss without severe adverse effect. Methods : 16 healthy volunteers consisting of an ephedra group (N=8) and a placebo group (N=8) were investigated. Study form was a randomized, controlled, double-blind clinical trial. The ephedra group took 12g of ephedra while the placebo group took 12g of glutinous rice powder. Both groups were measured with BCA (body composition analysis) on weight loss and with HRV (heart rate variability) on its adverse effect before and after medication. Results : The following results were obtained after taking 12g of ephedra for 14 days. In the ephedra group, body weight reduced significantly. In the placebo group, there were no significant differences of body weight between before and after placebo treatment. There was a slight increase of heart beat rate and deactivation of cardiac activity. Parasympathetic nerves were deactivated, but balances of autonomic nervous system were well maintained. Conclusions : The results suggest that ephedra in healthy adults tends to reduce body weight and deactivation of autonomic nervous system and cardiac activity.

• Korean journal of food and cookery science
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• v.28 no.6
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• pp.763-771
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• 2012

Physicochemical and sensory characteristics of pound cakes containing Angelica gigas NAKAI(Korean Angelica) with various levels of rice flour were investigated in this study. There were significant differences in the specific gravity of dough, and it had the lowest value of 0.848 in the control group. The weight of pound cakes was significantly increased by addition of rice flour, but the volume, specific volume and baking loss rate were significantly decreased by addition of rice flour. The moisture content and pH of pound cakes were found to increase with increasing rice flour content. DPPH radical scavenging activity of the control group was 51.02%, whereas pound cakes with rice flour ranged from 51.90~55.75%. The L value of brightness was increased, but a and b values were decreased significantly by addition of rice flour. In all of items of texture, the control group was higher than those of the pound cakes prepared with various levels of rice flour. Sensory evaluation scores in terms of appearance, flavor, taste, texture and overall preference for pound cakes showed that 50% and 75% substituted sample groups were higher than those of the other groups. The results of this study suggest that addition of 50~75% rice flour is the best substitution ratio for Korean Angelica pound cakes.