• KOREAN JOURNAL OF CROP SCIENCE
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• v.24 no.3
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• pp.7-12
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• 1979

Seven hundred and forty eight rice cultivars were screened for drought tolerance at seedling stage in a special green house. A number of cultivars such as Wonkiljo, Hanyangdo, YR 52-$_{x}\textrm{BF}_7-67, Satominori, Mamoriaka, Akanomochi 114, Thkebenimochi, IR 937-55-3, IR2735-F_3B-6-2, IR 2871-53-2, $_{x}\textrm{BFI76}^9/Dwan, Khoo lliok Mali-4-2-105, Os6, Palawan, IRAT10, TOS 2583 and H-l05 seemed to be tolerant to drought at seedling stage. There was negative correlation between drought resistance score and growth of plant height and water content of culm and leaf after drought treatment, and highly positive correlation between resistance to blast and resistance to drought at seedling stage. There was no relationship between drought resistance and germination speed, plant height before drought treatment.

• Asian Journal of Turfgrass Science
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• v.6 no.1
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• pp.11-22
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• 1992

To determine the use of waste materials as root zone soil mixtures for turfgrass culture, the effects of paper mill sludge and briquet ash on physical and chemical properties of soil and growth of turfgrasses were examined. Three turfgrass species of zoysiagrass(Zoysia japonicaSteud.). kentycky bluegrass(Poa pratensis L. 'Ram I') and creeping bentgrass(Agrostis panistris Huds 'Persucross') were cultured in 32cm diameter plastic pots containing various soil mixtures. The basic ingredients used for mixtures included sand(SD), field soil(SL), paper mill sludge(PS), sphagnum peat moss(PM) and briquet ash(BA). Seven combinations using these ingreients were mixed in different percentage by volume as follows: SD+SL+PM(80:10.10), SH+SL+PS(80:10:10), SD-PM(80:20), SD+PS (80:20), SD+BA(80:20), SD+BA+PM(60:20:20) and SD+BA+PS(60:20:20). 1. Paper mill sludge showed pH of 6.6, more than 30% of organic matter content, and higher concentrations of total N, P, k, Ca, Mg and CEC. Bulk density, fild moisture capacity and electrical conductivity of soil mixtures were increased by the comimation of 10~20% PS by volume. 2. Briquet ash showed pH of 8.0, and higher levels of P, k, Ca and Mg than those of field soiks. Bulk density, field moisture capacity and hardenss of soil mixtures were increased but vertical water flow rate and electrical conductivity were decreased by the combination of 20% BA by volume. 3. Phytotoxic effects of PS and BA on growth of turfgrasses were not found. Shoot growth of all three species was higher in soil combination of SD+BA+PS than that of SD+SL+PM added with fertilizer. However, root growth was better in soil mixtures combined with PM. Soil mixtureomposed of 60% SD, 20% BA and 20% PS by volume was most effective on growth of all three species. 4. Paper mill sludge resulted in higher N level in the leaf tissue. The contents of heavy metals such as Cd and Ph did not vary significantly among soil mixtures and species. However, the Mn level was 2~3 times higher in plants growh in mixtures containing PM compared with others, and especially it was higher in creeping bentgrass than other species.

• Korean Journal of Plant Resources
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• v.20 no.2
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• pp.129-132
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• 2007

It summarize result that test 3 years since 2002 allowing back 4 processing for disregard to supply basis data of method of cultivation establishment examining raw meat and quantity by the nitrogen additional fertilizer amount after Saururus chinensis 1th harvesting, is as following, Plant height, size of leaf, Stem diameter, water saving, goods leave, foliar such as the number of tillering and growth of rhizoma are good by long or, thick or, many tendency the nitrogen additional fertilizer using as a trial amount is much after the first harvesting. When foliar amount uses 158 kg/10a provision for disregard 3, 6, 9kg/10a because is increased the nitrogen additional fertilizer using as a trial amount is much night watch, each 20%, 42%, 60% rose, Rutin of constituent content was augmented tendency nitrogen additional fertilizer amount used is much, and quercitrin is high more or less in nitrogen additional fertilizer 3kg/10a using as a trials.

• Korean Journal of Medicinal Crop Science
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• v.15 no.5
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• pp.352-356
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• 2007

The present study was investigated the anti-oxidative effects of aloe vera ingestion on brain and kidney in aged rats by monitoring several oxidative-related parameters. Male specific pathogen-free Fischer 344 rats were randomly divided into four groups of five rat each: Group A was fed test chow without aloe supplementation; Group B was fed a diet containing a 1% freeze-dried aloe filet; Group C was fed a diet containing a 1% charcoal-processed, freeze-dried aloe filet; and Group D was fed a diet containing a charcoal-processed, freeze-dried, whole leaf aloe in drinking water. Analyses of tissues were done at 4 months and 16 months of age. Results showed that a long-term intake of aloe, regardless of the preparation used, enhanced antioxidant defenses against lipid peroxidation, as indicated by reduced phosphatidylcholine hydroperoxide levels in both brain and kidney. The additional benefit of aloe intake on the anti-oxidative action was evidenced by enhanced superoxide dismutase and catalase activity in all aloe-ingested groups. Another beneficial effect of aloe shown in this study, although not an anti-oxidative parameter, was its cholesterol-lowering effect as detected in brain and kidney with significant decreases at age16 months of aloe-fed rats. Based on these findings, we conclude that a long-term dietary aloe supplementation modulated the anti-oxidative defense systems and cholesterol level.

• Journal of Ecology and Environment
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• v.35 no.3
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• pp.203-212
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• 2012

The physiological effects of elevated $CO_2$ concentration and temperature were examined for Quercus gilva and Q. glauca grown under control (ambient $CO_2$ and temperature) and treatment (elevated $CO_2$ and temperature) conditions for 39 months. The objective of the study was to measure the long-term responses, in physiological parameters, of two oaks species exposed to elevated $CO_2$ and temperature. The photosynthetic rate of Q. gilva was found to be decreased, but that of Q. glauca was not significantly affected, after long-term exposure to elevated $CO_2$ and temperature. Stomatal conductance of Q. glauca was reduced by 21.7%, but that of Q. gilva was not significantly affected, by long-term exposure to $CO_2$ and temperature. However, the transpiration rate of the two oak species decreased. Water use efficiency of Q. gilva was not significantly affected by elevated $CO_2$ and temperature, while that of Q. glauca was increased by 56.6%. The leaves of Q. gilva grown under treatment conditions had an increased C:N ratio due to their reduced nitrogen content, while those of Q. glauca were not significantly affected by long-term exposure to elevated $CO_2$ and temperature. These results suggest that the long-term responses to elevated $CO_2$ and temperature between Q. gilva and Q. glauca are different, and that Q. gilva, the endangered species, is more sensitive to elevated $CO_2$ and temperature than Q. glauca.

• Proceedings of the KSRS Conference
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• 2007.10a
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• pp.243-245
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• 2007

This study was begun to classify the paddy fields by the rice varieties and to monitor the temporal change in rice growth using SAR backscatter coefficients $({\sigma}^{circ})$. For nine fine-beam mode images of Radarsat-1 SAR, a growing period time-series of backscatter coefficients was set up from April to October in 2005, and was compared with the field-measured rice growth parameters such as LAI (leaf area index), plant height, fresh and dry biomass, and water content in grain and plant for 45 parcels in Dangjin-gun, Chungcheongnam Province, South Korea. The average backscatter coefficients for early-maturing rice varieties (13 parcels) were ranged from -18.17dB to -6.06dB and were lower than for medium-late maturing rice varieties during most of the growing season. At around the heading stage (July 30) for early-maturing rice, both rice crops showed the highest backscatter coefficient values and the difference was the greatest before harvesting early-maturing rice. The temporal difference in backscatter coefficients between rice varieties was expected to play a key role to identify early-maturing rice fields. On the other hand, comparison with field-measured rice growth parameters showed that the backscatter coefficients decreased or stayed on the plateau after heading stage even though the growth of rice canopy advanced.

• Korean Journal of Medicinal Crop Science
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• v.25 no.3
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• pp.160-164
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• 2017

Background: This study were performed to determine the effect of root pruning of Zizyphus jujuba var. inermis (Bunge) Rehder. Root cutting inhibit vegetative growth and promote reproductive growth as temporarily reducing growth, net assimilation, water potential of leaf and cytokinin level. Methods and Results: The root pruning was treated of the root cutting widths 50, and 80 ㎝ and the root cutting depths 10, and 20 cm. The amount of root pruning and the number of suckers were the highest in the root-pruning treatment at a width of 50 cm and a depth of 20 cm. The blooming time was from June 18 to 20, and no difference was observed in the blooming time among the root-pruning treatments. The number of flowers was rather higher in the root-pruning treatment at a width of 50 cm and a depth of 20 cm and at a width of 80 cm and a depth of 20 cm. The percentage of fruit setting was higher in the plants whose roots were pruned at a depth of 20 cm than in the untreated plants. The fruit size, fruit weight, and sugar content showed no difference among the root-pruning treatments. Conclusions: The results showed that percentage of fruit setting increased with root pruning, while no difference was observed in the growth and fruit quality of plants.

• Journal of The Korean Society of Agricultural Engineers
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• v.56 no.5
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• pp.55-65
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• 2014

Radar remote sensing is appropriate for rice monitoring because the areas where this crop is cultivated are often cloudy and rainy. Especially, Synthetic Aperture Radar (SAR) can acquire remote sensing information with a high temporal resolution in tropical and subtropical regions due to its all-weather capability. This paper analyzes the relationships between backscattering coefficients of rice measured by RADARSAT-2 SAR and growth parameters during a rice growth period. And we applied the relationships to crop monitoring of paddy rice in North Korea. As a result, plant height and Leaf Area Index (LAI) increased until Day Of Year (DOY) 234 and then decreased, while fresh weight and dry weight increased until DOY 253. Correlation coefficients revealed that Horizontal transmit and Horizontal receive polarization (HH)-polarization backscattering coefficients were correlated highly with plant height (r=0.95), fresh weight (r=0.92), vegetation water content (r=0.91), LAI (r=0.90), and dry weight (r=0.89). Based on the observed relationships between backscattering coefficients and variables of cultivation, prediction equations were developed using the HH-polarization backscattering coefficients. Concerning the evaluation for the applicability of the LAI distribution from RADARSAT-2, the LAI statistic was evaluated in comparison with LAI distribution from RapidEye image. And LAI distributions in Pyongyang were presented to show spatial variability for unaccessible areas.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.4
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• pp.434-439
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• 2008

The amount of salt to make seed sorting solution of the specific gravity of 1.13 was reconsidered and determined as 3.8 kg salt in 18 L water, which is lower amount than currently used. Five rice cultivars were examined. Percent germination and seedling emergence were not similar. Seedling emergence rate of Japonica varieties, Nampyungbyeo and Daerypbyeo-1 were 87% and 95% under specific gravity of 1.13, respectively. Seedling emergence rate of Tongil type variety, Dasanbyeo was as high as 67% in specific gravity of 1.06. Seedling emergence rate of waxy rice, Hwasunchalbyeo and Aranghangchalbyeo were examined. Seedling emergence rate was 94% in both cultivars in specific gravity of 1.04. Seedling emergence rate was same in specific gravity of 1.08 which is generally used for selecting seed currently. Early growth (plant height, leaf number, and dry weight) were not significantly different by specific gravity within species. In all cultivars except waxy rice, highest seedling emergence rate was observed in specific gravity of 1.13 which is currently used for selection and decreased as specific gravity is lowed. However, considering total amount of seeds in each group of specific gravity, amount of seed in lower specific gravity group is relatively small and total seedling emergence rate within variety dose not show big difference. However, if seeds with low speicific gravity are produced due to the bad grain filling condition and consequently total seed content of low specific gravity increases, results will be differnt. Reduction in total growth and yield could occur. It will be important to comply with the seed sorting criterion of 1.13 for Japonica, 1.06 for Tongil, and 1.04 for waxy rice variety to ensure the maximum rice growth and yield.

• Journal of Biosystems Engineering
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• v.41 no.4
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• pp.365-372
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• 2016

Purpose: Tea is the most frequently consumed drink worldwide, next to water. About 75% of the total world tea production includes black tea, and withering is one of the major processing steps critical for the quality of black tea. There are two types of tea withering methods: physical and chemical withering. Withering can be achieved by using tat, tunnel, drum, and trough withering systems. Of these, the trough withering system is the most commonly used. This study focuses on the different types of withering, their effect on the various quality attributes of tea, and other aspects of withering methods that affect superior quality tea. Results: During physical withering, tea shoots loose moisture content that drops from approximately 70-80% to 60-70% (wet basis). This leads to increased sap concentration in tea leaf cells, and turgid leaves become flaccid. It also prevents tea shoots from damage during maceration or rolling. During chemical withering, complex chemical compounds break down into simpler ones volatile flavor compounds, amino acids, and simple sugars are formed. Withering increases enzymatic activities as well as the concentration of caffeine. Research indicates that about 15% of chlorophyll degradation occurs during withering. It is also reported that during withering lipids break down into simpler compounds and catechin levels decrease. Improper withering can cause adverse effects on subsequent manufacturing operations, such as maceration, rolling, fermentation, drying, and tea storage. Conclusion: Freshly harvested leaves are conditioned physically and chemically for subsequent processing. There is no specified withering duration, but 14-18 h is generally considered the optimum period. Proper and even withering of tea shoots greatly depends on the standards of plucking, handling, transportation, environmental conditions, time, and temperature. Thus, to ensure consumption of high quality tea, the withering step must be monitored carefully.