• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.54 no.1
• /
• pp.88-103
• /
• 2009

The volatile and semi-volatile compounds of 5 accessions of domestic scented and 25 accessions of introduced scented were extracted by solid phase microextraction (SPME) and analyzed by gas chromatographymass spectrum (GC-MS). A total of 156 volatile and semivolatile compounds were identified from 30 accessions of aromatic rice, including 32 alcohols, 25 acids, 25 ketones, 21 hydrocarbon, 18 esters, 16 aldehydes, 4 ethers, 5 amines, 2 phenols, 2 bases, and 8 miscellaneous compounds. By UPGMA/Neighbor-join tree analysis, the thirty accessions of aromatic rice could be classified into seven groups according to the major odor or aroma compounds. Group I included indica type of Basmati varieties. Group II and Group IV included japonica type introduced scented. Group III consisted only Hyangmibyeo1ho in domestic scented. Group V and Group VII included indica type of Basmati and non-Basmati varities. Group VI included four of domestic scented of seven accessions excepted Basmati6129, Basmati 6311, and Seratus Malam.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.17 no.3
• /
• pp.267-274
• /
• 2017

Recently, several researches have been studied on agricultural automation system according to convergence of IT technology with agriculture. An automatic control system of the growth environment in crops is one of the these researches. The controls of damages caused by diseases and insects pest in crops are mainly carried out by manual mode or semi-automatic mode because of farmer's concerns for poor efficiency. But, this situation needs to be improved because it occurs various problems, such as human exposure to toxic pesticides, environmental pollution and waste due to drug overuse. In order to solve these problems, we developed an automatic quantity control system which based on the amount of pesticides for area under cultivation. The amount of pesticides is calculated according to the manufacturer's instruction for pesticides. To verify the effectiveness of our developed automatic system, we also compared with the systems of manual mode and the semi-automatic mode. The experimental results of a pest control performance of an automatic quantity control system showed that automatic system can reduce overuse of drugs. These results suggested that it can be expected to replace the existing system, with equivalent effectiveness to the manual mode.

• Journal of Forest and Environmental Science
• /
• v.38 no.3
• /
• pp.184-194
• /
• 2022

Triplochiton scleroxylon K. Schum is the plant species most affected by logging activities in the East Region of Cameroon due to its market value. This logging has impacted the ecological niche of the fern plant for which limited research has been done. The aim of this study is to contribute towards improving knowledge of fern richness and biomass on T. scleroxylon within the Central African sub-region. Fern data collection was done on 20 felled/harvested T. scleroxylon where, in addition to fern inventory, fern biomass was collected by the destructive method. The diameter and height of T. scleroxylon measured were used as explanatory variables in allometric equations for fern biomass estimation. Fern inventory was characterized using diversity index. Eight fern species were recorded on T. scleroxylon (≈5 species/T. scleroxylon). The minimum diameter where fern could be found is 59.4 cm. The average fern biomass found was 23.62 kg/T. scleroxylon. Pearson correlation coefficient showed a positive correlation (r>0.55) between fern biomass and T. scleroxylon diameter. For allometric equation, the logarithmic model improved better the adjustment than the non-logarithmic model. However, the quality of the adjustment is improved more when only the diameter is considered as an explanatory variable. Fern biomass is estimated to 90.08 kg/ha^-1 with 76.02 kg/ha^-1 being lost due to T. scleroxylon exploitation in the study area. This study is a contribution towards increasing knowledge of fern diversity specific to T. scleroxylon, and also fern biomass contribution to climate change mitigation and the potential carbon loss due to T. scleroxylon exploitation.

• The Plant Pathology Journal
• /
• v.40 no.1
• /
• pp.59-72
• /
• 2024

A comprehensive survey of mungbean-growing areas was conducted to observe leaf spot disease caused by Alternaria alternata. Alternaria leaf spot symptoms were observed on the leaves. Diversity of 50 genotypes of mungbean was assessed against A. alternata and data on pathological traits was subjected to cluster analysis. The results showed that genotypes of mungbean were grouped into four clusters based on resistance parameters under the influence of disease. The principal component biplot demonstrated that all the disease-related parameters (% disease incidence, % disease intensity, lesion area, and % of infection) were strongly correlated with each other. Alt a 1 gene that is precisely found in Alternaria species and is responsible for virulence and pathogenicity. Alt a 1 gene was amplified using gene specific primers. The isolated pathogen produced similar symptoms when inoculated on mungbean and tobacco. The sequence analysis of the internal transcribed spacer (ITS) region, a 600 bp fragment amplified using specific primers, ITS1 and ITS2 showed 100% identity with A. alternata. Potato virus X (PVX) -based silencing vector expressing Alt a 1 gene was constructed to control this pathogen through RNA interference in tobacco. Out of 50 inoculated plants, 9 showed delayed onset of disease. Furthermore, to confirm our findings at molecular level semi-quantitative reverse transcriptase polymerase chain reaction was used. Both phenotypic and molecular investigation indicated that RNAi induced through the VIGS vector was efficacious in resisting the pathogen in the model host, Tobacco (Nicotiana tabacum). To the best of our knowledge, this study has been reported for the first time.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.12 no.3
• /
• pp.2019-2028
• /
• 1970

1. Experiments were made for the efficient plowing method by the 4 wheel tractor, the results are as follow; 1) In case of plowing of inner side of the field, the efficient turning method to be the smallest turning time is the $\Omega$-shaped turning method in the turning distance less than 2r (r is the minimum turning radius of the tractor), and also, it is the U-shaped turning method in the turning distance larger than 2r. 2) 2.5r is most efficient in the unit turning section 'w' on plowing of the inner side of the field. 3) In case of plowing of outer side of the field, intermitted plowing method is efficient in case of W>-0.0345 L + 35.84, and also, semi-followed plowing method is efficient in case of W<-0.0345 L + 35.84. 4) The smaller the width of outer side of outer side of the field 'I' is, the higher is the plowing efficiency, and it is estimated that the minimum value 2r is suitable to 'I' in plowing of inner side and outer side of the field. 2. Study on the correlation between the unit field and plowing efficiencies obtained the following results; 1) plowing efficienies increase generally according as length-width ratio L/W and area A increase. 2) Percent of increase of plowing efficiencies decreases generally according as length-width ratio and area enlarge. 3) The limit that change of T is large owing to L/W is 6 for 20 a, 5 for 30 a, 4 for 50 a, 3 for 80 a, less than 2.5 for 100 a, generally, in L/W-T curve. 4) Rate of change of T-A curve is similar to rate of change of $T=A-\frac{2}{3}$ curve in spite of influence of L/W. 5) In case that length-width ratio is more than 3, effects of increase of 10 a area influenced upon plowing efficiencies are as much as effects of about 5 increase of length width ratio without correlation of size of the field. 6) In case that length-width ratio is 2 to 3, effects of increase of 10 a area influenced upon plowing efficiencies are as much as effects of about 4 to 2 increase of length-width ratio without correlation of size of the field, and the effects decrease according as not only length-width ratio decreases but also area increases, generally.

• Analytical Science and Technology
• /
• v.15 no.2
• /
• pp.149-156
• /
• 2002

In this study, the levels of DEHA, carbaryl, and amitrole contained in the fresh water fishes and amphibians were determined. The 31 sampling sites were selected including 29 sites along the several rivers and 2 sites from the well-known wet lands. The rivers consists of the Han, Nakdong, Kum, Youngsan, and other small scaled rivers. DEHA was detected from 10 sites, but carbaryl and amitrole were not detected at any sites. The highest average concentration of DEHA was determined from the Kum River by $52.7{\mu}g/kg$. In the detected 10 sites, the average concentration of DEHA from fishes was $40.0{\mu}g/kg$, and that from amphibians was $8.90{\mu}g/kg$ which indicates that 5 times more DEHA was observed from fishes than amphibians. The detection frequency from fishes was 10/62 while that from amphibians was 2/62, and the highest concentration from fishes was $95.5{\mu}g/kg$ (crucians from Kongjoo) and that from amphibians was $12.1{\mu}g/kg$ (bullfrog from Najoo). Among the 10 detected sites, 6 sites were agricultural area and the other 4 sites were semi-urban area.

• Journal of agricultural medicine and community health
• /
• v.40 no.2
• /
• pp.80-92
• /
• 2015

Objectives: To clarify the association between dust from large construction sites and allergic and respiratory conditions among residents in Sejong city. Methods: We included 379 individuals older than 50 years from three areas of Sejong city; two areas near construction sites and one area for a comparison. Prevalence of self-reported allergic and respiratory conditions was compared across the three areas using logistic regression to adjust for covariates including age, gender, smoking, and educational attainment. A total of 16 individuals were interviewed to take details of the residents' experiences of construction work. Results: Those living in the nearby areas around construction sites were generally found to have the increased prevalence for all allergic and respiratory conditions. Odds Ratio(OR)s for cough and sneezing among the six symptoms and allergic rhinitis among the three diagnosed diseases reached statistical significance but only OR for cough remained significant after adjustment: adjusted OR for cough was 2.63 (95% CI, 1.07-6.46). Two relevant themes emerged from semi-structured interview were; 1) most residents from the affected area reported a considerable level of exposure to construction dust, 2) about half of them noted that construction dust influences allergic- and respiratory health. Conclusions: General pattern provides suggestive evidence that living close to construction sites may be positively associated with elevated risks of allergic and respiratory conditions. Efforts should be made to establish preventive measures and a comprehensive in-depth health impact assessment on this issue.

• Korean Journal of Breeding Science
• /
• v.40 no.3
• /
• pp.308-313
• /
• 2008

"Jeokjoong", a white winter wheat (Triticum aestivum L.) variety was developed from the cross "Keumkang"/"Tapdong". "Jeokjoong" is an awned, semi-dwarf and soft white winter wheat, similar to "Keumkang" (check variety). The heading and maturing date of "Jeokjoong" were similar to "Keumkang". Culm and spike length of "Jeokjoong" were 78 cm and 7.5 cm, similar to "Keumkang". "Jeokjoong" had lower test weight (800 g) and lower 1,000-grain weight (40.1 g) than "Keumkang" (811 g and 44.0 g, respectively). It had resistance to winter hardiness, wet-soil tolerance and lodging tolerance. "Jeokjoong" showed moderate to scab in test of specific character although "Keumkang" is susceptible to scab. "Jeokjoong" had lower flour yield (69.2%) and ash content (0.36%) than "Keumkang" (72.0% and 0.41%, respectively) and similar flour color to "Keumkang". It showed lower protein content (8.9%) and SDS-sedimentation volume (36.8 ml) and shorter mixograph mixing time (3.5 min) than "Keumkang" (11.0%, 59.7 ml and 4.5 min, respectively). Amylose content and pasting properties of "Jeokjoong" were similar to "Keumkang". "Jeokjoong" had softer and more elastic texture of cooked noodles than "Keumkang". Average yield of "Jeokjoong" in the regional adaptation yield trial was 6.19 MT ha-1 in upland and 5.33 MT/ha in paddy field, which was 19% and 16% higher than those of "Keumkang" (5.21 MT/ha and 4.58 MT/ha, respectively). "Jeokjoong" would be suitable for the area above the daily minimum temperature of $-10^{\circ}C$ in January in Korean peninsula.

• Korean Journal of Breeding Science
• /
• v.40 no.2
• /
• pp.153-158
• /
• 2008

"Baegjoong", a white winter wheat (Triticum aestivum L.) cultivar was developed by the National Institute of Crop Science, RDA. It was derived from the cross "Keumkang"/"Olgeuru" during 1996. "Baegjoong" was evaluated as "Iksan307" in Advanced Yield Trial Test in 2004. It was tested in the regional yield trial test between 2005 and 2007. "Baegjoong" is an awned, semi-dwarf and soft white winter wheat, similar to "Keumkang" (check cultivar). The heading and maturing date of "Baegjoong" were similar to "Keumkang". Culm and spike length of "Baegjoong" were 77 cm and 7.5 cm, similar to "Keumkang". "Baegjoong" had lower test weight (802 g) and lower 1,000-grain weight (39.8 g) than "Keumkang" (811 g and 44.0 g, respectively). It had resistance to winter hardiness, wet-soil tolerance and lodging tolerance. "Baegjoong" showed moderate to pre-harvest sprouting (23.9%) although "Keumkang" is susceptible to pre-harvest sprouting (38.9%). "Baegjoong" had similar flour yield (72.4%) and ash content (0.41%) to "Keumkang" (72.0% and 0.41%, respectively) and similar flour color to "Keumkang". It showed lower protein content (8.8%) and SDS-sedimentation volume (35.3 ml) and shorter mixograph mixing time (3.8 min) than "Keumkang" (11.0%, 59.7 ml and 4.5 min, respectively). Amylose content and pasting properties of "Baegjoong" were similar to "Keumkang". "Baegjoong" had softer and more elastic texture of cooked noodles than "Keumkang". Average yield of "Baegjoong" in the regional adaptation yield trial was $5.88\;MT\;ha^{-1}$ in upland and 5.35 MT ha-1 in paddy field, which was 13% and 17% higher than those of "Keumkang" ($5.21\;MT\;ha^{-1}$ and $4.58\;MT\;ha^{-1}$, respectively). "Baegjoong" would be suitable for the area above the daily minimum temperature of $-10^{\circ}C$ in January in Korean peninsula.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.29 no.1B
• /
• pp.11-22
• /
• 2009

Long-term rainfall-runoff modeling is a key element in the Earth's hydrological cycle, and associated with many different aspects such as dam design, drought management, river management flow, reservoir management for water supply, water right permission or coordinate, water quality prediction. In this regard, hydrologists have used the hydrologic models for design criteria, water resources assessment, planning and management as a main tool. Most of rainfall-runoff studies, however, were not carefully performed in terms of considering reservoir effects. In particular, the downstream where is severely affected by reservoir was poorly dealt in modeling rainfall-runoff process. Moreover, the effects can considerably affect overall the rainfallrunoff process. An objective of this study, thus, is to evaluate the impact of reservoir operation on rainfall-runoff process. The proposed approach is applied to Anseong watershed, where is in a mixed rural/urban setting of the area and in Korea, and has been experienced by flood damage due to heavy rainfall. It has been greatly paid attention to the agricultural reservoirs in terms of flood protection in Korea. To further investigate the reservoir effects, a comprehensive assessment for the results are discussed. Results of simulations that included reservoir in the model showed the effect of storage appeared in spring and autumn when rainfall was not concentrated. In periods of heavy rainfall, however, downstream runoff increased in simulations that do not consider reservoir factor. Flow duration curve showed that changes in streamflow depending upon the presence or absence of reservoir factor were particularly noticeable in ninety-five day flow and low flow.