• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.59 no.2
• /
• pp.194-200
• /
• 2014

Skin ridge (SR) is a irregular line shape that stand out in epidermal layer on sweet potato (Ipomoea batatas Lam.). SR reduced marketable value of storage root in sweet potato. It would be occurred by accumulation of starch in epidermal layer. SR rate was more highly increased in early planting. SR rate was under 3% in 7 varieties 'Geonpoongmi', 'Yeonhwangmi', 'Geonmi' etc and the rate of two varieties 'Healthymi', 'Borami' were up to 30%. SR rate was positively correlated with vine weight. SR rate was the highest in 120 days after planting. As leaf area index was reduced to 3, 4, 5 and 6 (non-topping) by topping, it was hard to fine SR occurrence in topping treated sweet potato. Topping treatment, however, caused decrease in yield overall. Therefore, topping treatment for decreasing of SR was not recommended in agricultural practice of sweet potato.

• Journal of Sericultural and Entomological Science
• /
• v.32 no.2
• /
• pp.79-84
• /
• 1990

To make clear the changes of the amount of reserve substances in the bark of stem and root of mulberry graftages after planting, studies were carried with mulberry graftages classified into three groups of 7.0-7.9mm, 9.0-9.9mm and 11.0-11.9mm in diameter of stems at 3cm above their base. The results obtained were as follow : 1. The dry weight of stem and root bark gradually decreased with growth of new shoots till about five weeks after planting, and from then it increased. 2. The duration of new shoots growth depending on the reserve substance was limited for 6-7 weeks after planting. In no fertilized group, the length of new shoots increased up to 6-7 weeks, form then decrease. 3. Dry leaf yield three weeks after planting was found to be no difference in the same diameter of saplings between with and without fertilization. 4. The content of chlorophyll in the leaves was higher in thicker group and in fertilized group than thinner and no fertilized one, respectively. 5. There was no difference in the amount of carbohydrates of the bark of stem and root among the stem diameters. There was a transient increase in the amount of total sugar in the bark of stem and root in the first three weeks after planting, followed by gradual decline up to five weeks. The amount of reducing sugar in the bark of stem and root increased both in fertilized and in no fertilized group up to three weeks after planting, and then it decreased. There was a gradual decline in the content of starch in the bark of stem and root both in fertilized and in no fertilized group up to five weeks after planting, followed by gradual increase.

• Korean Journal of Soil Science and Fertilizer
• /
• v.23 no.2
• /
• pp.123-127
• /
• 1990

The results of the investigation on the relationship between the varietal difference of photosynthesis capacity and carbohydrate metabolism and the susceptibility to sudden wilting are as follow: 1. Yushin and Milyang 23, varieties in which sudden wilting occurs easily, showed that the photosynthesis capacity at the young panicle formation stage and the contents of chlorophyll of the flag leaf were lower than Jinhung which did not show sudden wilting. 2. Respiration consumption index (${\frac{amount\;of\;respiration}{amount\;of\;assimilation}{\time}100$) of Yushin and Milyang 23 were higher than Jinhung's. 3. Regarding sugar contents of each internode at the ripening stage, the contents of the second and third internodes of Yushin were lower than Jinhung, but no varietal difference was found in the 1st internode. 4. The starch content of the Yushin node sharply decreased compared with Jinhung at the ripening stage. In Jinhung it was especially higher in lowerinternodes, but in the third internode of Yushin. was not more than 50% of that in higher internode's.

• Korean Journal of Plant Resources
• /
• v.23 no.5
• /
• pp.465-479
• /
• 2010

This study was carried out to classify the regional folk plants in the inland of Gyeongsangbuk-do. According to the survey results from 582 survey sheets of 126 residents at 85 places of 17 counties and cities from March to October, 2009, the folk plants in the inland of Gyeongsangbuk-do consisted of a total 254 taxa; 76 families, 207 genera, 225 species, 2 subspecies, 26 varieties, and 1 form. The use by its usage was: 216 taxa; edible, 82 taxa; medicinal, 30 taxa; dye, 3 taxa; aroma, 4 taxa; spice, 4 taxa; ornamental, 1 taxa; fiber, 2 taxa; oil, 1 taxa; starch, 5 taxa; fuel, 9 taxa; others, respectively, so the edible use is the highest. The most useful part was the leaf, followed by stem and root. The folk plants of 3 head families from Yeongyang and Cheongsong were 42 taxa. The consistency comparison between the scientific name and the local name were the highest in the 50's and the lowest in 80's.

• Korean Journal of Plant Resources
• /
• v.26 no.1
• /
• pp.90-102
• /
• 2013

This study was carried out in order to catalogue the folk plants of 5 counties and cities of Chungcheongbuk-do Province from March to October, 2011. 429 pages of field notes relating to the folk plants were collected from approximately 92 local inhabitants and analyzed subsequently. The identified folk plants were of 173 taxa, composed of 150 species, 1 subspecies, 22 varieties and 129 genera under 56 families. Naturalized plants were included. The use by its usage was: 349 taxa; edible, 68 taxa; medicinal, 2 taxa; dye, 1 taxa; aroma, 4 taxa; spice, 1, taxa; ornamental, 3 taxa; oil, 1 taxa; starch, 18 taxa; others respectively, so the edible use is the highest. The most useful part was the leaf, followed by stem, and whole plant. The consistency comparison between the scientific name and the local name were the highest in the 50's and the lowest in 90's.

• Korean Journal of Soil Science and Fertilizer
• /
• v.41 no.4
• /
• pp.247-253
• /
• 2008

Winter annual green manure crops may be an effective tool for environmental-friendly agriculture system. The effect of legume (hairy vetch), non-legume (rye) and N fertilization ($190kg\;N\;ha^{-1}$) was examined and compared on red-pepper yield, nitrogen uptake, carbohydrate composition, and soil N and C contents. We monitored soil N and C for 120 days after incorporation (DAI) of green manures or mineral fertilizer. The mineralization of nitrogen reached the maximum around 30 DAI. The amount of inorganic nitrogen supplied by mineralization of hairy vetch residue was greater with than chemical N or rye. Photosynthetic rate was similar by 70 DAT in all treatments however, it in rye-incorporated red-pepper presented a sharp decline at later growth period. Leaf total nitrogen was greater with hairy vetch and chemical N than rye throughout the experiment. The soluble sugar increased steadily in all treatments from 40 to 110 days after transplanting (DAT) whereas starch showed a tendency of great decrease. Hairy vetch greatly promoted red-pepper growth by the later period however, chemical N showed the highest fruit yields.

• Korean Journal of Environmental Agriculture
• /
• v.27 no.4
• /
• pp.428-434
• /
• 2008

The objective of this study is to investigate the effect of the level of $CO_2$ (370 and $650{\mu}mol\;mol^{-1}$) and temperature (ambient and ambient+$5^{\circ}C$) on tomato growth and fruit characteristics as affected by the application rate of N-fertilizer (68 and $204\;N\;kg\;ha^{-1}$), for the purpose of evaluating the influence of elevated $CO_2$ and temperature on tomato crop. The elevated atmospheric $CO_2$ and temperature increased the plant height and stem diameter for tomato crop, while the differences among the nitrogen(N) application rates were not significantly different. Under the elevated $CO_2$, temperature, and a higher N application rate, the biomass of aerial part increased. The fruit yield showed the same result as the biomass except for the elevated temperature. The elevated temperature made the size of fruit move toward the small, but the elevated $CO_2$ and the application of N-fertilizer were vice versa. The sugar content and pH of fruit juice were affected by nitrogen application rate, but not by the elevated $CO_2$ and temperature. These results showed that both the elevated $CO_2$ and temperature stimulated the vegetative growth of aerial parts for tomato, but each effects on the yield of fruit showed an opposite result between the elevated temperature and $CO_2$. In conclusion, the elevated $CO_2$ increased tomato yield and the ratio of large size of fruit, but the elevated temperature did not. Therefore, to secure the productivity of tomato as nowadays in future environment, it will need to develop new breeder as high temperature-tolerable tomato species or new type of cropping systems.

• Asian-Australasian Journal of Animal Sciences
• /
• v.32 no.4
• /
• pp.574-584
• /
• 2019

Objective: Research was conducted to test the effect of including fiber-rich feedstuffs in practical pig diets on nutrient digestibility, nitrogen balance and ammonia emissions from slurry. Methods: Three Vietnamese fiber sources were screened, namely cassava leaf meal (CL), cassava root residue (CR), and tofu by-product (TF). Accordingly, a control diet (Con) with 10% of dietary non-starch polysaccharides (NSP) and three test diets including one of the three fiber-rich feedstuffs to reach 15% of NSP were formulated. All formulated diets had the same level of crude protein (CP), in vitro ileal protein digestible and metabolisable energy, whereas the in vitro hindgut volatile fatty acid (VFA) production of the test diets was 12% to 20% higher than the control diet. Forty growing barrows with initial body weight at $28.6{\pm}1.93kg$ ($mean{\pm}standard$ deviation) were allocated to the four treatments. When pigs reached about 50 kg of body weight, four pigs from each treatment were used for a nitrogen balance trial and ammonia emission assessment, the remaining six pigs continued the second period of the feeding trial. Results: The TF treatment increased fecal VFA by 33% as compared with the control treatment (p = 0.07), suggesting stimulation of the hindgut fermentation. However, urinary N was not significantly reduced or shifted to fecal N, nor was slurry pH decreased. Accordingly, ammonia emissions were not mitigated. CR and CL treatments failed to enhance in vivo hindgut fermentation, as assessed by fecal VFA and purine bases. On the contrary, the reduction of CP digestibility in the CL treatment enhanced ammonia emissions from slurry. Conclusion: Dietary inclusion of cassava and tofu byproducts through an increase of dietary NSP from 10% to 15% might stimulate fecal VFA excretion but this does not guarantee a reduction in ammonia emissions from slurry, while its interaction with protein digestibility even might enhance enhanced ammonia emission.

• Korean journal of applied entomology
• /
• v.25 no.1 s.66
• /
• pp.41-46
• /
• 1986

Exogenous factor and nutrients affecting for conidial germination of Colletetrichum dematium f. sp. capsicum causing red pepper anthracnose were studied by slide germination test. Optimum temperature of conidial germination was at $28^{\circ}C$, ranging 15 to $35^{\circ}C$. Optimum pH was at 5.5, ranging 4.5 to 8.0, and more than 90% of relative humidity (RH) was optimum. Poor conidial germination of the fungus was observed on sterile distilled water, but potato sucrose broth (PSB), red pepper fruit broth (RPFB), green pepper fruit broth (GPFB) and pepper leaf broth (PLB) furnished a satisfactory nutrients for conidial germination. Exogenous supply of carbon and nitrogen sources were essential for conidial germination, while potassium, phosphorous and sulfur were not evident as that for carbon and nitrogen. Soluble starch was the most suitable as a carbon source for conidial germination and followed by D-glucose, D-galactose and lactose in that order. Maximum germination was attained in the $1{\times}10^4$ conidia per ml. Germination was decreased with increment of conidial concentration, and in the density of $5{\times}10^4$ conida per ml, germination was nearly supipressed. It suggested existing a self-inhibitor. Non-washed conidia germinated more than washed conidia, and conidial germination was also gradually decreased by increasing conidial density.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.59 no.1
• /
• pp.101-108
• /
• 2014

This study was conducted to investigate the effect of nitrogen rates on the growth characteristics and yield of maize in agricultural fields with the stream. This indicates the necessity and optimal level of nitrous fertilization to examine the possibilities of quantity enhancement. Plant height and ear height of maize were not significantly different among the nitrogen rates. Stem diameter and leaf area index increased in the nitrogen treatment compared to untreated control. Changes of photosynthetic rate in maize leaves depending on nitrogen treatments increased as much as nitrogen rates were increased up to the highest level, 36 kg per 10a. NDF and ADF content levels of maize were investigated with different nitrogen rates regardless of treatments. In the case of NDF, it showed a tendency to decrease after 8 days of tasseling date. ADF had also decreased after 15 days of tasseling date. Nitrogen uptake of maize leaves with different nitrogen rates showed the highest level, $4.9g\;kg^{-1}$ with 36 kg per 10a on the tasseling date. Ear length and 100-kernel weight, there were no significant differences according to yield and the components with different nitrogen rates. Ear diameter and kernel number, nitrogen rates of 18 kg and 36 kg were increased compared to nitrogen rate of 9 kg per 10a and untreated control. The pericarps in 9 kg nitrogen rate and control were thicker than those of 18 kg and 36 kg treatment. The yield, 18 kg, 36 kg, and 9 kg treatments were increased by 10.96%, 9.27%, and 3.31%, compared to control. The component analysis on maize kernel with different nitrogen rates, starch showed no significant differences among treatments. Total sugar in 18 kg nitrogen treatment represented the highest content level, 6.37%. In addition, Amylopectin in 18 kg treatment showed the highest content level of 90.38%. However, amylose in 18 kg treatment showed the lowest level, 9.62% which drew a conclusion that waxy of 18 kg treatment is considered to be the strongest one. From the results described above, nitrous fertilization is essential to grow maize in agricultural fields with the stream. The optimum level of nitrous fertilization is considered 18 kg per 10a.