• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.47 no.3
• /
• pp.151-156
• /
• 2002

The heritability of sink-source characters was estimated by regression coefficient between F$_2$ and F$_{5}$ in two crosses of IR 66738-118-1-2/Gayabyeo and the Ilpumbyeo/YR 15965 Acp 33. In order to get the some basic information for breeding of high yielding rice, genetic resources of new plant type with low tiller and heavy panicle were used. Most of the sink and source characters in Ilpumbyeo/YR 15965 Acp 33 cross showed high heritability over than 0.224. But the specific leaf area and sink-source ratio displayed low heritability being 0.009 and 0.013, respectively. Heritability of all sink and source characters in IR 66738-118-1-2/Gayabyeo cross ranged from 0.115 to 0.247. Correlation coefficient between yield and yield components in both combination were in the ranged between 0.001 and 0.247. But correlations among the yield components were not significant. Correlations between the yield and sink-source characters in both combinations were also highly significant. Particularly, correlation between the grain tiling ratio and most of the sink-source characters in IR 66738-118-1-2/Gayabyeo cross were not significant. In Ilpumbyeo/YR 15965 Acp 33 cross, correlations between grain filling ratio and source characters were positively significant. but sink characters (sink capacity and sink-source ratio, etc) were negatively significant.

• Horticultural Science & Technology
• /
• v.31 no.1
• /
• pp.24-31
• /
• 2013

This study was conducted to determine the characteristics of quality and yield in potatoes grown at paddy field before rice transplantation during the spring season. Three potato cultivars ('Jowon', 'Haryeong', and 'Goun') were grown in Gangneung (asl 5 m) and Seocheon (asl 20 m). In both locations, weather condition belonged to the fourth zone (spring cropping) in potato production location's distribution of Korea. Daily mean soil temperature in both the locations was $0.2-0.6^{\circ}C$ lower than air temperature, while soil moisture was adequate level to potato growth in spite of spring drought. TR ratio was not affected by location, but by cultivar. Specific gravity, starch content, dry matter rate, and yield were significantly influenced by location and by cultivar. There was no difference in total tuber number by location, however there was a large gap in marketable tuber yield according to locations and cultivars. There were high negative relationships between yield and main qualities such as dry matter rate and starch content, while high positive correlation was observed between main qualities. It was possible to produce potato before rice transplanting at drained paddy fields located in representative two locations of potato spring cropping and their characteristics in growth and quality were similar to those generally well known in upland cultivation. Paddy field was thought to be more favorable than upland in terms of available soil moisture supply against spring drought. Further research, however, was needed to increase soil temperature and also preliminary review on proper cultivar according to location seemed to be needed for high yield.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.50 no.4
• /
• pp.221-237
• /
• 2005

For developing the site-specific fertilizer management strategies of crop, it is essential to know the spatial variability of soil factors and to assess their influence on the variability of crop growth and yield. In 2002 and 2003 cropping seasons within-field spatial variability of rice growth and yield was examined in relation to spatial variation of soil properties in the· two paddy fields having each area of ca. $6,600m^2$ in Suwon, Korea. The fields were managed without fertilizer or with uniform application of N, P, and K fertilizer under direct-seeded and transplanted rice. Stable soil properties such as content of clay (Clay), total nitrogen (TN), organic mater (OM), silica (Si), cation exchange capacity (CEC), and rice growth and yield were measured in each grid of $10\times10m$. The two fields showed quite similar spatial variation in soil properties, showing the smallest coefficient of variation (CV) in Clay $(7.6\%)$ and the largest in Si $(21.4\%)$. The CV of plant growth parameters measured at panicle initiation (PIS) and heading stage (HD) ranged from 6 to $38\%$, and that of rice yield ranged from 11 to $21\%$. CEC, OM, TN, and available Si showed significant correlations with rice growth and yield. Multiple linear regression model with stepwise procedure selected independent variables of N fertilizer level, climate condition and soil properties, explaining as much as $76\%$ of yield variability, of which $21.6\%$ is ascribed to soil properties. Among the soil properties, the most important soil factors causing yield spatial variability was OM, followed by Si, TN, and CEC. Boundary line response of rice yield to soil properties was represented well by Mitcherich equation (negative exponential equation) that was used to quantify the influence of soil properties on rice yield, and then the Law of the Minimum was used to identify the soil limiting factor for each grid. This boundary line approach using five stable soil properties as limiting factor explained an average of about $50\%$ of the spatial yield variability. Although the determination coefficient was not very high, an advantage of the method was that it identified clearly which soil parameter was yield limiting factor and where it was distributed in the field.

• Korean Journal of Medicinal Crop Science
• /
• v.26 no.3
• /
• pp.220-226
• /
• 2018

Background: Atractylodes japonica Koidz. and Atractylodes macrocephala Koidz. belong to the family (Asteraceae). Their rhizomes, called white Atractylodes rhizomes, are used in traditional medicine. To address some issues with their cultivation, we recently developed eight hybrid cultivars by interspecific hybridization of A. japonica and A. macrocephala. This study was conducted to screen the hybrid cultivars that have high amounts of active ingredients and yield ability. Methods and Results: Experiments were conducted using the eight hybrid cultivars and A. macrocephala (control cultivar) in the experimental field of the department of Herbal Crop Research located in Eumseong, South Korea. We investigated the growth characteristics of the aerial and underground parts. Among the cultivars, 'Sanwon' had the highest rhizome dry weight (53.8 g/plant), followed by 'Dachul' (50.0 g/plant). In addition, the content of atractylenolide I, II, III and total active ingredients were investigated using high-performance liquid chromatography. Compared with A. macrocephala, most of the inter-specific hybrid cultivars had a higher content of active ingredients and yield ability. Conclusions: Through study, we established the superior quality of Atractylodes inter-specific hybrid cultivars. In particularly, it was found that 'Dachul' may be grown as a superior cultivar, with high amount of active ingredients as well as yield ability.

• Microbiology and Biotechnology Letters
• /
• v.17 no.5
• /
• pp.421-428
• /
• 1989

A soil bacterium synthesizing an extremely viscous biopolymer was isolated and identified as Pseudomonas delafieldii. The optimal pH and temperature for the growth were 6.5 and 3$0^{\circ}C$, respectively. Maximum specific growth rate was 0.24 h$^{-1}$. The specific polysaccharide productivity, growth yield and product yield were 6.25 mg/g-cell/h, 54.5% and 38.39%, respectively. The polysaccharide was presumed to be $\beta$-glucan containing glucose and gluconolactone (1.9：1.0 in molar ratio) and 1.35 % acetyl group, Element analysis showed that it contained carbon (31.85%) and hydrogen (5.15%). The weight average molecular weight by GPC was 5.64$\times$10$^7$. The intrinsic viscosity was 42.84 dl/g.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.27 no.3
• /
• pp.425-432
• /
• 1998

The strain producing L-lactic acid from starch was isolated from kimchi. The isolated strain was identified as a homofermentative Streptococcus sp. through its morphological, cultural, biochemical characteristics, and named Streptococcus sp. JEJ-6. Lactic acids are of two types, one L-specific and the other D-specific form in a stereospecific form. Streptococcus sp. JEJ-6 produced selectively L-lactic acid from all of the tested carbon sources. The optimum conditions for the L-lactic acid production from the isolated microorganism were determined. For the maximum yield of L-lactic acid from Streptococcus sp. JEJ-6, the cell should be harvested at the early stationary phase, and the growth temperature, pH, and NaCl concentration should be 37$^{\circ}C$, pH 7.0 and 0.1%, respectively. 4% Soluble starch as substrate and organic nitrogen sources such as peptone and yeast extract should be used for the best yield. The optimum pH of the nicotinamide adenine dinucleotide(NAD)-dependent and NAD-independent lactate dehydrogenase(LDH) activities was pH 8.5 and pH 7.0, respectively.

• Journal of Microbiology and Biotechnology
• /
• v.19 no.11
• /
• pp.1408-1414
• /
• 2009

The obtention of high yields of purified plasmid DNA is viewed as an essential issue to be considered towards efficient production of DNA vaccines and therapeutic plasmids. In this work, Escherichia coli $DH5\alpha$. bearing the pVAXI-LacZ plasmid was grown in a developed semi-defined medium at different temperatures and tryptone concentrations. Analysis of pDNA yields and E. coli morphology revealed that at higher temperatures (37 and $40^{\circ}C$), higher specific yields and E. coli filamentation were obtained. However, the best results were achieved when a lower tryptone concentration was used. This approach was shown to be a powerful tool to promote plasmid amplification, keeping the desirable plasmid structure, and favoring the attainment of quality. Our results suggest that by using tryptone alone as an amino acid source, pDNA amplification was improved and a specific yield of 20.43 mg pDNA/g dcw was achieved, proving that this strategy can improve pDNA yield even at a small scale.

• Journal of Environmental Science International
• /
• v.1 no.1
• /
• pp.1.1-11
• /
• 1992

To find heavy metal-specific effects on the photosynthetic apparatus of higher plants, we investigated effects of $CuCl_2$, HgCl_2$ and $ZnCl_2$ on electron transport activity and chlorophyll fluorescence induction kinetics of chloroplasts isolated from barley seedlings. Effects on some related processes such as germination, growth and photosynthetic pigments of the test plants were also studied. Germination and growth rate were inhibited in a concentration-dependent manner by these metals. Mercury was shown to be the most potent inhibitor of germination, growth and biosynthesis of photosynthetic pigments of barley plants. In the inhibition of electron transport activity, quantum yield of PS II, and chlorophyll fluorescence induction kinetics of chloroplasts isolated from barley seedlings, mercury chloride showed more pronounced effects than other two metals. Contrary to the effects of other two metals, mercury chloride increased variable fluorescence significantly and abolished qE in the fluorescence induction kinetics from broken chloroplasts of barley seedlings. This increase in variable fluorescence is due to the inhibition of the electron transport chain after PS ll and the following dark reactions. The inhibition of qE could be attributed to the interruption of pH formation and do-epoxidation of violaxathin to zeaxanthin in thylakoids by mercury. This unique effect of mercury on chlorophyll fluorescence induction pattern could be used as a good indicator for testing the presence and/or the concentration of mercury in the samples contaminated with heavy metals.

• Journal of Microbiology and Biotechnology
• /
• v.18 no.5
• /
• pp.918-925
• /
• 2008

Controlling the light energy and major nutrients is important for high cell density culture of cyanobacterial cells. The growth phase of Anabaena variabilis can be divided into an exponential growth phase and a deceleration phase. In this study, the cell growth in the deceleration phase showed a linear growth pattern. Both the period of the exponential growth phase and the average cell growth rate in the deceleration phase increased by controlling the light intensity. To control the light intensity, the specific irradiation rate was maintained above $10\;{\mu}mol/s/g$ dry cell by increasing the incident light intensity stepwise. The final cell density increased by controlling the nutrient supply. For the control of the nutrient supply, nitrate, phosphate, and sulfate were intermittently added based on the growth yield, along with the combined control of light intensity and nutrient concentration. Under these control conditions, both final cell concentration and cell productivity increased, to 8.2 g/l and 1.9 g/l/day, respectively.

• Journal of Microbiology and Biotechnology
• /
• v.32 no.5
• /
• pp.672-679
• /
• 2022

Microbial lipases are used widely in the synthesis of various compounds due to their substrate specificity and position specificity. 4-Ethyl malate (4-EM) made from diethyl malate (DEM) is an important starting material used to make argon fluoride (ArF) photoresist. We tested several microbial lipases and found that Photobacterium lipolyticum M37 lipase position-specifically hydrolyzed DEM to produce 4-EM. We purified the reaction product through silica gel chromatography and confirmed that it was 4-EM through nuclear magnetic resonance analysis. To mass-produce 4-EM, DEM hydrolysis reaction was performed using an enzyme reactor system that could automatically control the temperature and pH. Effects of temperature and pH on the reaction process were investigated. As a result, 50℃ and pH 4.0 were confirmed as optimal reaction conditions, meaning that M37 was specifically an acid lipase. When the substrate concentration was increased to 6% corresponding to 0.32 M, the reaction yield reached almost 100%. When the substrate concentration was further increased to 12%, the reaction yield was 81%. This enzyme reactor system and position-specific M37 lipase can be used to mass-produce 4-EM, which is required to synthesize ArF photoresist.