• Journal of The Korean Society of Grassland and Forage Science
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• v.9 no.3
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• pp.174-178
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• 1989

The investigation was carried out to identify the main pathogen infected with sheath blight in corn plant during 1986-1987. The main fungi of sheath blight isolated from corn plant was identified as Rhizoctonia sobni. Sheath blight in corn plant was first found in early July and infected extremely from late July to end August. Severe sheath blight disease was observed in Gyeongido (Yeoju and Suweon) and Jeonnam (Kwangju) area. The rate of attack was associatied with management and cultural environments of corn plant. Dense planting increased sheath blight, but application of cattle compost reduced the rate of infection. A positive correlation was found between infection rate of shealth blight and concentration of soluble carbohydrate in corn plant (r=0.96). The varieties of Jinjuok, Suweon 83, Suweon 87, Suweon 89, P.3055, P.3160, DK689 and XCG 51 showed remarkable tolerance to sheath blight disease.

• Korean journal of food and cookery science
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• v.8 no.3
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• pp.255-263
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• 1992

Pasting characteristics and amylose-surfactant complex forming ability of sweet potato starch were investigated after defatting and the addition of surfactants, such as SSL (sodium steamyl-2-lactylate) Dimodan (mono/di glyceride) and SE (sucrose ester) with different concentrations. All starch granules were smooth and round, there were no damages to starch granules after defatting and surfactant addition. amylose content of surfactant added stach decreased and me order of decrease was SSL, SE and Dimodan. The cornplex forming ability of SE added starch increased according to increasing HLB value. As surfactants concentration increased, amylose complex formig ability increased. In case of gelatinization patterns by amylograph, the initial pasting temperature of surfactant added starches was higher than mat of untreated or defatted starches, but viscosity at each temperature were all decreased. Soluble carbohydrate and leached amylose of starches increased at increasing temperature, those of surfactant added starches decreased at each temperature in the order of SSL, SE and Dimodan.

• Journal of the Korean Society of Food Culture
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• v.26 no.5
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• pp.513-520
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• 2011

This study was carried out to investigate the physicochemical properties of mung bean starch and the texture of cold-stored (5$^{\circ}C$ for 0, 24, 48, and 72 hours) mung bean starch gels added with soy bean oil (0, 2, 4, 6%). The swelling power of mung bean starch added with soy bean oil did not significantly change, whereas solubility increased significantly. Soluble carbohydrate content of mung bean starch added with soy bean oil decreased without any significant differences, whereas soluble amylose content decreased significantly. In RVA viscosity, pasting temperature and peak viscosity of mung bean starch added with soy bean oil were not significantly different, whereas minimum viscosity decreased and breakdown and consistency increased significantly. In RVA viscosity, there were no differences according to concentration of soy bean oil. DSC thermograms show that onset temperature of mung bean starch added with soy bean oil did not significantly change, whereas the enthalpy increased in the case of 4% and 6% oil addition. Rupture properties of freshly prepared mung bean starch gels added with soy bean oil increased in the case of 2% and 4% oil addition, and oil addition to mung bean starch gels suppressed changes in rupture properties during cold storage. There were no significant differences in the texture of freshly prepared mung bean starch gels added with soy bean oil, whereas hardness, chewiness, and gumminess of cold-stored mung bean starch gels added with soy bean oil decreased. In the above textural charactristics, there were no differences due to concentration of soy bean oil. Thus, the addition of 2-4% soy bean oil to mung bean starch is appropriate for improving the quality characteristics of cold-stored mung bean starch gels.

• Journal of Korean Society on Water Environment
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• v.20 no.4
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• pp.327-332
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• 2004

This study was carried out to examine the effect of gamma irradiation on the physico-chemical characteristics and ultimate anaerobic biodegradability of sewage sludge. The results found that the solubilization rates of SCOD in wasted activated sludge(WAS) and thickened sludge(T-S) with gamma irradiation of 3kGy were 8 times and 7 times greater than these of the raw WAS and T-S without the irradiation, respectively; each soluble concentration protein were 4 times and 3 times greater than these of the raw WAS and T-S; each soluble carbohydrate concentration was 8 times and 6 times greater than these of the raw WAS and T-S. The ultimate anaerobic biodegradabilities of WAS and T-S with gamma irradiation were 51 % and 50%, which corresponds to each 8% and 10% greater than these of the raw sludges. Approximately 83% and 81% of the each biodegradable substrates in the irradiated WAS and the T-S were degraded within 11 days with the first order decay rate coefficients, $k_1$ that ranged $0.143{\sim}0.164day^{-1}$ for WAS and $0.134{\sim}0.152day^{-1}$ for T-S. Based on the results, it can be concluded that when irradiated with gamma the solubilization of sewage sludge greatly increases resulting in substrates suitable for the subsequent biological treatment processes.

• Journal of Ecology and Environment
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• v.37 no.3
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• pp.131-137
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• 2014

To investigate the solute pattern of salt marsh plants in Suncheon Bay in Korea, plants and soil samples were collected at three sites from July to September 2011. The soil pH around the investigated species was weakly alkaline, 6.9-8.1. The total ion and Cl- content of site 1 gradually increased, while those of site 2 and site 3 were lowest in August and highest in September. The exchangeable $Ca^{2+}$, $Mg^{2+}$ and $K^+$ in the soil were relatively constant during the study period, but the soil exchangeable $Na^+$ content was variable. Carex scabrifolia and Phragmites communis had constant leaf water content and very high concentrations of soluble carbohydrates during the study period. However, Suaeda malacosperma and S. japonica had high leaf water content and constant very low soluble carbohydrate concentrations. Carex scabrifolia accumulated similar amounts of $Na^+$ and $K^+$ ions in its leaves. Phragmites communis contained a high concentration of $K^+$ ions. Suada japonica and S. malacosperma had more $Na^+$ and $Cl^-$ ions than $K^+$ ions in their leaves. Suaeda japonica had higher levels of glycine betaine in its leaves under saline conditions than C. scabrifolia and P. communis. Consequently, the physiological characteristics of salt marsh chenopodiaceous plants (S. japonica and S. malacosperma) were the high storage capacity for inorganic ions (especially alkali cations and chloride) and accumulation of glycine betaine, but monocotyledonous plant species (C. scabrifolia and P. communis) showed high $K^+$concentrations, efficient regulation of ionic uptake, and accumulation of soluble carbohydrates. These characteristics might enable salt marsh plants to grow in saline habitats.

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.2
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• pp.145-152
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• 2002

To compare the Carbon metabolic response to high temperature stress in Zoysiagrass [Zoysia matrella (L.) Merr.] and Creeping bentgrass (Agrostis palustris Huds) with respect to heat tolerance, C metabolites were determined from April to September. Sampling was carried out on an established golf course (Muan Country Club, Chonnam, Korea). Shoot mass(g Dry weight per hole cup) of creeping bentgrass started to decrease from June and recovered from August whereas that of zoysiagrass was less varied. Chlorophyll content in creeping bentgrass was significantly higher than zoysiagrass until July, and then decreased by 43% from July to August. Zoysiagrass contained higher soluble sugar than creeping bentgrass throughout experimental period. Soluble sugar in zoysiagrass increased about 58% from April to May, and less varied until August. Soluble sugar in creeping bentgrass slightly increased until July and sharply decreased at August. Starch concentration in zoysiagrass continuously decreased to September after a significant increase from April to May. A remarkable fluctuation in both starch and fluctuation concentration was observed between June and August showing high accumulation for June to July and high degradation for July to August. These results suggest that through creeping bentgrass suffers much severely from high temperature stress than zoysiagrass especially June to August. An active accumulation and degradation in nonstructural carbohydrate in creeping bentgrass during this period might be associated with heat stress.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.4
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• pp.232-242
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• 2002

To investigate the effects of arbuscular mycorrhizal (AM) fungus (Glomus intraradices) colonization on drought-stress tolerance, leaf water potential, chlorophyll concentration, P content and carbohydrate composition were examined in perennial ryegrass (Lolium perenne L.) plants exposed to drought-stressed or well-watered conditions. Drought stress significantly decreased leaf water potential, P content and leaf growth. These drought-induced damages were moderated by mycorrhizal colonization. Drought stress decreased the concentration of soluble sugars in shoots. AM plants had a higher foliar soluble sugar than non-AM plants under drought stress condition. Drought stress depressed the accumulation of starch and fructan in shoots, but stimulated in roots. Under drought-stressed condition, starch concentration in roots was higher in non-AM plants than in AM plants. Fructan was the largest pool of carbohydrates, showing the highest initial concentration and the highest net increase for 28 days of treatment. Drought stress slightly decreased fructan concentration in shoots, but remarkably increased in roots. Under drought-stressed condition, fructan concentrations in non-AM and AM shoots at day 28 were 18.7% and 13.3% lower than the corresponding values measured at well-watered plants. However, in the roots, fructan accumulation caused by drought was lessen 13.6% by mycorrhizal colonization. The results obtained suggest that mycorrhizal colonization improves drought tolerance of the host plants by maintaining higher leaf water status and P status, and by retaining more foliar soluble sugars.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.1
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• pp.44-49
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• 2008

Sufficient inorganic nitrogen supply for crop growth is crucial for economically sustainable organic farming. The effects of an application of cover crop biomass on crop growth, nitrogen utilization and carbohydrate composition were investigated during early stage. Short-term changes in soil nitrogen after incorporating fresh hairy vetch and rye shoots were measured. The inorganic nitrogen from cover crops reached the peak at 15 ($NH_4-N$) and 24 ($NO_3-N$) days after incorporation, and then decreased rapidly. The highest concentration of soil nitrate showed at 27 days of incorporation in hairy vetch and at 18 days in rye, and three fold differences exhibited between two treatments. Crop growth under hairy vetch or rye incorporation significantly differed. At 20 DAT, dry matter production in NPK and hairy vetch was about two fold greater than that in rye. Difference in decomposing rates of hairy vetch and rye had also influence on nitrogen status in leaves and roots of pepper plants. Total nitrogen was greater in NPK and hairy vetch than in rye until 20 DAT, whereas inorganic nitrogen (nitrate and nitrite) concentration was higher in rye. Temporal changes in soluble sugars and starch in pepper plants among treatments were similar, although difference in the amount existed. It was suggested that hairy vetch as an alternative nitrogen source promoted crop growth and mineral utilization during early growth stage, whereas an obvious effect in rye was not found.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.1
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• pp.48-53
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• 2002

To investigate the changes in the composition and pool size of carbohydrates under drought stress, white clover (Triforium repens L.) were exposed to -0.04 Mpa(well-watered, control) or to -0.12 Mpa (drought-stressed) of soil water potential during 28 days. Dry weight of leaves in drought-stressed plants was remarkably decreased by 45% within 14 days and 74% within 28 days compared to those of the control. Glucose concentration in drought-stressed plants was increased, while that of control was slightly decreased or remained at same level throughout experimental period. Fructose and sucrose concentrations in leaves were not significantly changed for drought-stressed plants, but those of the control were significantly decreased on plant after 14 days. Fructose and sucrose concentrations in stolon of control plants were sharply decreased, while that of drought-stressed plants was less varied. Those concentrations in roots were generally increased in drought-stressed plants. The concentration of total soluble sugars at 28 day was 438.0 and 632.6 mg $g^{-l}$ dwt. in control and drought stressed plants, respectively. Starch concentration of stolon and roots of control plants was significantly increased to 2.0 and 1.4 times of initial level, respectively, whereas those of drought stressed plants was nearly same level or slightly decreased compared to initial level.l.

• Journal of Plant Biology
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• v.37 no.2
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• pp.195-201
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• 1994

In order to study the effects of polyamine inhibitors and polyamines on adventitious root formation, the correlation between adventitious root formation and carbohydrate metabolism was investigated in inoculated soybean (Glycine max L.) cotyledons at the concentration of $10^{-3}\;M$ methylglyoxal bis-(guanylhydrazone)[MGBG], and $10^{-3}\;M$ MGBG plus $10^{-5}\;M$ polyamines (putrescine, spermidine and spermine), respectively, for the adventitious root formation medium. The contents of starch, maltose and sucrose were lower in control and were higher in the treatments containing $10^{-3}\;M$ MGBG, and $10^{-3}\;M$ MGBG plus $10^{-5}\;M$ polyamines during culture. It was shown that the soluble sugar levels, except glucose, were higher than that of control in most of the treatments and the change in glucose contents tended to be similar to that control. The amylase activity increased in control and MGBG treatment, the maltase activity was higher in control and the invertase activity showed less substantial changes during culture.ulture.