• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.3
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• pp.147-151
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• 1998

The conductivity test is a measure of electrolytes leakage from plant tissue. The shorter the maturation period after heading was the greater electrical conductivity (EC) of rice seed. The polymer-coated seed was not different in EC compared with non-coated seed. As soaking time of rice seed increased, EC increased gradually. The EC varied from 9.9 to 20.7$\mu$S $cm^{-1}g^{-l}$ for control plots and from 21.3 to 41.7$\mu$S $cm^{-1}g^{-l}$ for heat-killed seeds which were produced by autoclaving seeds at 121$^{\circ}C$ for 20 minutes. The germination speed (the rate of 5th day) of rice seed was 94% at control plot, 83% at low temperature and 20% at high temperature. Besides, germination percentage was 95% for the control, 92% for the low temperature treatment and 39% for the high temperature treatment. The EC was negatively correlated (r=-0.771$^{**}$) with germination percentage at low temperature. Water uptake in seeds of 30, 40, 50 days after heading (DAH) was greater than that of 20 DAH. Plant height of seedlings was 9.84 cm for the control but 4.32 cm for the high temperature treatment, and the tallest for polymer-coated seed. Dry weight of seedlings was 0.841 g for the control and 0.287 g at high temperature. Besides, the polymer-coated seed was heavier than non-coated seed. The number of roots was largest from 40 to 50 DAH and polymer-coated seed, but was decreased from 20 to 30 DAH. The length of roots was 20.52 cm at control plot and 19.89 cm polymer-coated seed but 8.68 cm for the low temperature treatment and 7.28 cm for the high temperature treatment.

• Korean Journal of Food Science and Technology
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• v.36 no.3
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• pp.514-517
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• 2004

O157:H7, Salmonella typhimurium, Listeria monocytogenes were treated with aqueous chlorine dioxide to elucidate effect of aqueous chlorine dioxide treatment on major food-borne pathogenic bacteria. Survival plot of E.coli O157:H7 at 5 ppm chlorine dioxide showed typical first-order rate. After 5 min of treatment, cell number decreased by 1.5 log cycle. Survival plot slope gave D value of 3.37 min. S. typhimurium and L. monocytogenes showed biphasic curve. Aqueous chlorine dioxide treatment on S. typhimurium and L. monocytogenes resulted in bactericidal effect for 5 min, and thereafter no effect was observed under experimental conditions of this study. These results suggest concentration of chlorine dioxide is more important than treatment time, and 5 ppm chlorine dioxide treatment is not sufficient for sanitizing fresh vegetables.

• Korean Journal of Organic Agriculture
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• v.10 no.1
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• pp.65-74
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• 2002

The results of the experiment about the effect of the length of electrical stimulation treatment time on the yield components and NO$_3$ content in edible parts of 2 cherry type radishes(Raphanus salivas L.) were like followings. 1. The 2 hours electrical stimulation promoted the length of leaf and the enlargement of the root diameter of 'Comet' and 'Sakuranbo' cultivars, and their root diameters were increased by 14.7% and 12.8% respectively than that of the control. 2, The plot which showed the highest root fresh weight was the 2 hours stimulation plot in 'Comet' and 8 hours stimulation plot in 'Sakuranbo', and these results were approximately 39% higher than that of the control. 3. All of the electrically stimulated plots of 'Comet' and 'Sakuranbo' showed higher NO$^{[-10]}$ $_3$content in roots than the control. And the amount of NO$^{[-10]}$ 3 in their roots showed a remarkable positive correlation with the root diameter, the root fresh weight and the total fresh weight.

• Korean Journal of Organic Agriculture
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• v.14 no.4
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• pp.433-443
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• 2006

With treatment of Kitosan, Wood vinegear and EM(effective microoganism) which farmers call it as substance in fertilizing, conditioning and disease control substances, authors in vestigated on microorganisms change in soil and ealy growth characteristics of tomato. The results were summarized as follows: Among foliar application of kitosan, wood vinegear and EM(effective microoganism) treatments diluted by chitosan 500 times solution level was effective considering growth of tomato as compared other dilutions and control plot. Change of microorganism number in the soil for cultivation of tomato was increased with microorganism treatment plot as compared with control plot. Specially chitosan 500 times solution level showes the most significant effect.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.2
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• pp.78-88
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• 2003

This study was conducted to develop the plant-mat for ecological restoration which was formed as the thin multi-layers of woven nets, soil media, seeds, etc. The experimental site was selected at a slope of 240$m^2$ at the rear of Design College of Sangmyung University and divided into 8 sub-experimental plots (20$m^2$ each) according to mat types. (forest-type and grass-type mats with and without seed attachment, respectively) Also, the existing vegetation plot and the no-treatment plot were included in this experiment for comparison. The experiment construction was conducted on September 3, 2002. Mat covered plots regardless of seed attachment showed nearly no signs of erosion even if rainy season in summer compared to the no-treatment plot. Vegetation monitoring result showed that germination rates were somewhat high in both forest and grass-type mats without seed attachment in the initial germination stage. Although germination rates of seed attached mats were somewhat slower than non-seed attached mats in the germination stage, but over time, it showed a good rooting and shooting environment for germinated tree and grass species because of soil media existence within the mat. This indicates that while non seed-attached mats require follow-up maintenance, seed-attached mats does not require maintenance after rooting and germination.

• The Journal of Natural Sciences
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• v.5 no.1
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• pp.29-36
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• 1992

The experiment was conducted to evaluate the effects of organic fertilizer. Sarang of fermented poultry manure. Miwon glutamic acid fertilizer and poultry manure, on the growth and yield of radish cultivated in spring and autumn. 1) The growth of leaf length, leaf weight, root length, root diameter and root weight of radish in two culture types was stimulated in order of NPK, fermented poultry manure + 1/5NK, fermented poultry manure, poultry manure and control treatment, and chlorophyll and nitrogen content of leaf were increased in order of the above mentioned fertilizers.2) Yield decreased in fermented poultry manure plot of 450kg application comparison with NPK plot but the one of 1800kg fermented poultry manure was increased. The yield of 450kg Sarang plot was sufficient as compared with Korean average yield of spring and autumn culture.3) The difference of growth of radish between treatments of fermented poultry manure and NPK was lowered by continuous application of Sarang organic fertilizer.4) Soil nitrogen content and exchangeable Mg were similar in all treatments but soil pH, the contents of organic matter, $P_2 O_5$ and Ca were high in the fermented poultry manure treatment.

• Journal of The Korean Society of Agricultural Engineers
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• v.61 no.5
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• pp.23-31
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• 2019

Crop response to weather and internal water pressure changes is more sensitive to crop water stress than soil water content. Recently, its implementation to optimal irrigation scheduling has been receiving much attention. This study was conducted to determine and compare the theoretical crop water stress index (CWSI) using meterological data and canopy temperature collected from three different irrigation treatments, which were Tr-1 plot (rainfed), Tr-2 plot (50% of daily evapotranspiration (ET) irrigated) and Tr-3 plot (75% of daily evapotranspiration (ET) irrigated). The readings of canopy temperature and CWSI were significantly different among irrigation treatment schemes. The average canopy temperatures and CWSIs of Tr-1 and Tr-3 plots were $34.6^{\circ}C$ and $32.6^{\circ}C$, 0.79 and 0.64, respectively. Solar radiation had the biggest correlation with CWSI (R=0.68) which was followed by wind speed, relative humidity and air temperature. Overall, the findings of this study indicated that canopy temperatures and CWSIs could be further used for irrigation scheduling for crop growth.

• Korean Journal of Soil Science and Fertilizer
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• v.20 no.4
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• pp.375-385
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• 1987

This study was carried out to investigate the effects of pesticides on soil respiration, microflora and enzymes in loam soil, and on pathogenic microorganisms in continuous pepper cropping soil. The results are summarized as follows. No significant effect of pesticides on soil respiration was shown, with the exception of propoxur which slightly increased at $10{\mu}g\;g^{-1}$ treatment. When pesticides were treated, the amount of soil microorganisms generally decreased at the early stage of incubation and the number of microflora was much more decreased at 60-day incubation. When pesticides were treated, the amount of soil enzyme activity was inhibited at the early stage of incubation and gradually recovered at the last stage of incubation. The amount of polygalacturonase activity was increased at the 20-and 30-day incubation in propoxur treatment plot. The amount of ${\beta}$-glucosidase and dehydrogenase activity was increased at 20-and 60-day incubation in carbofuran and acephate treatment plot. The amount of phosphatase activity was increased at 60-day incubation in propoxur and isoprocarb treatment plot. The amount of Fusarium generally decreased in continuous pepper cropping soil, with the exception of isoprocarb and acephate treatment plot which significantly increased. The amount of Pythium increased at 60-day incubation with the exception of captan treatment plot which significantly decreased.

• Korean Journal of Medicinal Crop Science
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• v.9 no.2
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• pp.91-98
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• 2001

Scutellaria baicalensis G. was cultivated in plots of different soil textures which were sand loam(SL), loam(L) and clay loam(CL). Also three fertilizer conditions were used; non application (NA)treatment, rice straw manure(RSM) treatment and N-P-K, chemical fertilization(CF) treatment. The chemical-physical properties, such as organic matter, available phosphate, $K_2O$, CaO, clay contents and porosity ratio in CL plot with RSM application were the most proper in CL plot and RSM application for the culture of S. baicalensis plants. RSM had very high contents of total nitrogen, 2.25% and C/N ratios, 21.4. Thus the growth of shoot and root in loam plot with RSM treatment were greater compared to that of CL plot with NA treatment. Whereas, The highest baicalin, baicalein and wogonin contents in roots were found in CL plot with RSM treatment. There was significantly positive correlation between aerial and underground parts of plant, yield and contents of T-N, $K_2O$ but negatively correlated with the contents of baicalin, baicalein and wogonin in S. baicalensis roots.

• Korean journal of applied entomology
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• v.34 no.3
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• pp.256-265
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• 1995

The effect ground-cover weeds on the occurrence of apple pests and their natural enemies was studied in an apple orchard in Ahnsung, Kyung-gi do during seasons of 1993 and 1994. The major apple pests and their parasitoids and predators were surveyed on the apple tree canopy in tow experimental plots; a weed-free lot where all weeds were removed by herbicide treatment, and a mowed plot where weeds were allowed restrictly by cutting with an asickle. Also, a sweep net sampling was taken from ground-cover weeds in the mowed plot. There were no significant differences in the abundance of mite and aphids between two plots, although mite densities tend to be lower in the mowed plot. The apple leaf miner, Phyllonorycter ringoniella, was significantly fewer in the mowed plot,. The densities of natural enemies of mites and aphids were slightly higher in the mowed plot. The parasitism of apple leaf miner in the mowed plot was 6~10% and 20~25% higher than that in the weed-free plot in 1993 and 994, respectively. Several natural enemies such as Apanteles kuwayamai (Braconidae), Orius sauteri (Anthocoridae), Chrysopa sp. (Chrysopidae), coccinellidae, and Eulophidae were collected both from weeds and the apple trees, However, potential apple pests were not observed on weeds. The development of insect community on the apple tree canopy was restricted by the pesticide spray on apple trees, while the insect community on weeds was maintained without significant destruction by pesticides spray on apple trees. Consequentely, the ground-cover weeds under apple trees affected occurrences of apple pests and their natural enemies in apple trees. te specialist natural enemies such as apple leaf miner's parasitoids dispersed from weeds to the apple canopy and affected apple leaf miner density significantly. However, generalist predators that have preys available on weeds stayed on weeds, hence their control effects for mites and aphids on the apple canopy were low.