• 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.48 no.4
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• pp.305-311
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• 2015

Both low and high temperatures affect plant growth and development at whole plant level, tissue and even cell level through a variety of metabolic changes. Temperature stress is one of frequently occurring problems in greenhouse crops in summer and winter seasons due to the wide-spread year-round cultivation. In the present study, we investigated the extent of the inhibition of growth, macro-element uptake and soluble carbohydrate production, and the effect of extra-supply of minerals as a means of the recovery from temperature damage. Tomato plants were grown five different growth temperatures (15/8, 20/13, 28/21, 33/23 and $36/26^{\circ}C$), and extra-supply of minerals was composed of 1.5- and 2.0-fold stronger than the standard nutrition (1/2 strength of Hoagland's solution). Temperature stress significantly adversely affected tomato growth and mineral uptake, whereas soluble carbohydrate accumulation represented temperature-dependent response, more accumulation at low temperature and more consumption at high temperature. The soluble sugars in leaves and stems were mostly declined with the supply of extra-minerals at low and optimal temperatures, whereas remained unchanged at high temperature. The starch levels also remained unchanged or slightly decreased.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.6
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• pp.594-601
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• 1994

Effects of translocation on seed yield and carbon-nitrogen compounds at five leaf-pod ratios of soybean [Glycine max. (L.)Merr. ] culti bars, 'Paldalkong', 'Baekunkong', and 'Danyeobkong' were measured. The upper 50 and lower 50% of leaves and pods were subjected to treatments at growth stage R3. Three soybean cultivars showed the similar trends on changes in dry matter accumulation and on the contents of soluble sugar, starch and protein in seeds among the treatments. Mean stem dry weight was increased with upper leaf-lower pod and lower leaf-upper pod removals, and decreased with upper leaf and lower leaf removals. Leaf dry weight was appeared higher at the upper leaves among the treatments. Seed numbers and dry weights were decreased with leaf and leaf-pod removals, and were higher in lower part of the plants. Soluble sugar and starch contents in seeds were also showed slightly higher in lower part. Protein content of seeds was decreased in upper part with upper leaf removal and in lower part with lower leaf removal, however, that of the upper seeds was the highest with lower leaf removal. The results of this study are assumed that carbon and nitrogen compounds were translocated opposite directions and protein source was weak in remobilization for the long distance transport during the reproductive growth period of soybean plants.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.1
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• pp.96-114
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• 2000

Genetically selected beef cattle are fed high-energy diets in intensive production systems developed in industrial countries. This type of feeding can induce rumen dysfunctions that have to be corrected by farmers to optimise cost-effectiveness. The risk of rumen acidosis can be reduced by using slowly degradable starch, which partly escapes rumen fermentation and goes on to be digested in the small intestine. Additives are proposed to stabilise the rumen pH and restrict lactate accumulation, thus favouring the growth of cellulolytic bacteria and stimulating the digestion of the dietary plant cell wall fraction. This enhances the energy value of feeds when animals are fed maize silage for example. Supplementation of lipids to increase energy intake is known to influence the population of rumen protozoa and some associated rumen functions such as cellulolysis and proteolysis. The end products of rumen fermentation are also changed. Lipolysis and hydrogenation by rumen microbes alter the form of fatty acids supplied to animals. This effect is discussed in relation with the quality of lipids in beef and the implications for human health. Conditions for optimising the amount of amino acids from microbial proteins and dietary by-pass proteins flowing to the duodenum of ruminants, and their impact on beef production, are also examined.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.1
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• pp.55-58
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• 2000

Germination of sweet and super sweet corn is lower than normal corn due to the higher sugar and lower starch contents of kernels. Sweet corn seeds are easily deteriorated in the field under the unfavorable condition, therefore it is important to identify the optimal harvesting time for seed production. This trial was conducted to investigate the responses of germination percentage of shrunken-2(sh2), brittle(bt), sugary(su), and sugary enhancer(se) hybrids in relation to harvesting dates. Eight hybrids of four different gene sweet corns were harvested at 15, 20, 25, 30, 35, 40, 45, and 50 days after silking(DAS). Germination test was performed using paper towel method. Mean germination percentages across eight hybrids showed the highest value at 45 DAS. There were significant differences among genes and within gene for germination. Shrunken-2 hybrid Mecca was higher than su hybrids for germination, indicating that sh2 would not be poorer than su Late harvesting beyond the optimal harvesting date might not be desirable because of more lodging and ear rots. Theoretical optimal harvesting date estimated from the regression equation was 40.9 DAS, however, practical date for harvesting would be a few days later than the estimated date if seedling vigor might be considered. Kernel dry weight per ear showed similar response to germination. Regression equation showed the highest kernel dry weight at 40.7 DAS. Significant correlations between kernel dry weight and germination were observed, impling that kernel dry matter accumulation would be an important factor for germination.

• Food Science and Preservation
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• v.24 no.4
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• pp.491-496
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• 2017

Paddy rice is typically stored during postharvest until rice grain is processed into brown rice and milled rice by hulling and milling procedure, respectively. Recently, instead of storing paddy rice, storage of brown rice has been in the spotlight because it is more convenient and economically feasible. Different brown rice cultivars with varying amylose contents including waxy rice, medium-waxy rice, and non-glutinous rice were stored in room temperature storage for four months, and the changes in grain qualities of brown rice were evaluated. Amylose content significantly affected pasting properties in which rice cultivar with higher amylose content showed longer pasting time and higher peak viscosity. Storage also affected pasting viscosities, showing an increase in peak viscosity, but a decrease in breakdown viscosity. The changes in pasting viscosity during storage could be an important starch property for aged brown rice utilization. Waxy brown rice showed the weakest aging property in terms of free fatty acids (FFA) accumulation, whereas non-glutinous rice was more substantial grain quality against aging. The FFA values of two months storage were not significantly different from the initial FFA contents, suggesting that brown rice stored in room temperature for two months could be feasible for direct consumption of brown rice.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.215-215
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• 2022

Starch synthase proteins (SSI, SSII and SSIII) in rice are mainly involved in amylopectin synthesis mediating its chain elongation, and the functional loss of SSII can increase amylose accumulation through decreasing of amylopectin chain proportions. For purposes of identifying functional haplotypes and evolutionary analyses of this gene, SSII-1, we investigated 374 rice accessions belonging to different subgroups of origins. We subsequently performed bioinformatic analyses on their variations through haplotyping, resequencing and structuring based on different classified populations. Haplotyping of cultivated rice accessions using genetic variations within SSII-1 genomic region of chromosome 10 revealed a total of 8 haplotypes, representing 6 functional haplotypes by 4 non-synonymous SNPs of three different exons (1, 4 and 10), which effect on protein structure. Higher nucleotide diversity value was found in wild group (0.0055) compared to any of cultivated subpopulations, of which aus showed the most reduction of diversity value (0.0003). Tajima's D analysis exhibits the most Tajima's D value only in admixture group (0.3600) which appears to be the cause of a sudden population contraction by rare alleles scarcity. A clear separation of some wild accessions from the admixed cultivated subpopulations was observed in PCA and phylogenetic analysis. Similar admixed pattern of population structure was estimated with an increased K values of 2 to 8 where genetic components of almost all cultivated subpopulations were shared with the wild which can also be subsequently estimated by very low F_ST-values by -0.011 (wild-aromatic) and -0.003 (wild-admixture).

• Journal of Life Science
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• v.34 no.5
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• pp.296-303
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• 2024

Vinegar is a fermented food product created by fermenting various sugar- and starch-containing ingredients with microorganisms. It contains a variety of organic acids, sugars, amino acids, esters, and other compounds that contribute to its unique sensory properties. Vinegar is known for its potential benefits, including aiding digestion, lowering blood sugar levels, anti-obesity effects, and antioxidant properties. It is also believed to contribute to improving alkaline body conditions. This study was conducted to develop functional dried vinegar powder from naturally fermented vinegars. Unripe apple, brown rice, and black chokeberry (aronia) were fermented using Gluconacetobacter xylinus for 90-180 days. The filtrate vinegar was spray dried with 37.46% maltodextrin, 5% glucose, 1% citric acid, and 0.04% vitamin C. Analysis of the acidity, color difference, water and soluble solid content, and heat stability of dried vinegar (DV) confirmed that spray drying is a suitable method for powder production. Moreover, the DVs exhibited excellent sensory attributes and solubility. Among the DVs, aronia-DV showed the highest 1,1-diphenyl-2-picryl hydrazyl and 2,2-azobis (3- ethylbenzothiazoline-6-sulfonate) radical scavenging activity (36.7% and 75.3%) and reducing power (0.334) at 0.5 mg/ml concentration, respectively. The nitrite scavenging activity was highest in brown unripe apple-DV, followed by aronia-DV and brown rice-DV. In the anti-thrombosis activity assay, aronia-DV showed the highest prothrombin inhibition. The brown rice-DV exhibited lipid accumulation inhibitory activity in 3T3-L1 adipocytes without cell cytotoxicity. Our results suggest the potential for commercialization of dried vinegar, highlighting its diverse benefits and applications.

• Horticultural Science & Technology
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• v.31 no.6
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• pp.706-713
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• 2013

With pot-grown 4-year-old 'Fuyu' persimmon trees, this study evaluated the effect of different nitrogen (N) rates during summer on fruit characteristics, changes of leaf nutrients after harvest, reserve accumulation, and early growth the following year. A total of 0, 36 g N in June, and 72 g N in June and July was fertigated to each tree using urea solution. All the fruits were harvested on Nov. 3. Although not significant, fruits were larger for the 36 g and 72 g N than the 0 g N. Fruits for the 0 g N, having lower N concentration, were softer and had a better coloration and higher soluble solids, indicating that they matured earlier. SPAD value on Nov. 3 was 19.2 for the 0 g N and 54.9 for the 72 g N, and then the values linearly decreased in all the treatments by Nov. 14, exhibiting rapid leaf senescence. Specific leaf weight, being the lowest for the 0 g N, also gradually decreased during this period. Increasing N level significantly increased cross-sectional area of the trunk. Leaf N concentration on Nov. 3 was 0.87% for the 0 g N, whereas it was 1.18 and 1.52% for the 36 g and 72 g N, respectively. The N fertigation tended to increase leaf concentrations of soluble sugars, starch, and amino acids. Contents of N, P, K, soluble sugars, starch, and amino acids per unit leaf area gradually decreased in all the treatments during the 11 days after harvest, and the extent of the decrease was the lowest for the 0 g N. On the other hand, those of Ca, Mg, and protein did not consistently change during this period. The N fertigation resulted in higher concentrations of N in dormant shoots on Nov. 14, and although not great, it also increased soluble sugars, starch, amino acids, and protein. Clear differences were found in number of flower buds per one-year-old branch and total shoot length per tree the following year. The 72 g N trees had 5.6-fold more flower buds and 1.9-fold more shoot length, compared with those of 0 g N trees. However, it was noted that tree growth the following year was not significantly different between the 36 g and 72 g N the previous year. It was concluded that N rate during summer should be adjusted with considering the changes of fruit maturation, mobilization of leaf nutrients, and reserve accumulation.