• Journal of Forest and Environmental Science
• /
• v.38 no.4
• /
• pp.256-262
• /
• 2022

The timing of seed harvesting is an important decision in the management of seed orchards because it affects seed quality and yield. To investigate the effect of cone harvest time on seed quality and determine the optimal harvesting time, cones were regularly collected in seven times and germination tests were performed at each harvest time in two clonal seed orchards of Chamaecyparis obtusa. As cones developed, the percentage of seed germination increased before cone moisture content began to decrease significantly. The moisture contents of cones were highest at the first collection as 68.3% and 67.3% in Jeju and Gochang seed orchards respectively. At this time, germination speed was slowest, indicating poor seed vigour. The highest germination was found at the second stage in Jeju (36.5%) and at the seventh stage in Gochang (28.6%) seed orchard. The germination speed increased as cone moisture content decreased. Additionally, changes of seed vigour differed among the developmental stages in both seed orchards. Consequently, the optimal cone harvest time of C. obtusa seed orchards in Jeju was early September when high germination percentage was obtained. In Gochang seed orchards, late October was optimal cone harvest time when the germination speed was fast and the cone moisture content decreased.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2021.06a
• /
• pp.143-143
• /
• 2021

Climate change indicators, mainly frequent drought which has happened since the drought of 1994, 1995, and 2012 causing the devastating effect to the agricultural sector, and could be more disruptive given the context of climate change indicators by increasing the temperature and more variable and extreme precipitation. Changes in frequency, duration, and severity of droughts will have enormous impacts on agriculture production and water management. Since both the possibility of drought manifestation and substantial yield losses, we are propositioning an integrated method for evaluating past and future agriculture drought hazards that depend on models' simulations in the Hung-up watershed. to discuss the question of how climate change might influence the impact of extreme agriculture drought by assessing the potential changes in temporal trends of agriculture drought. we will calculate the temporal trends of future drought through drought indices Standardized Precipitation Evapotranspiration Index, Standardized Precipitation Index, and Palmer drought severity index by using observed data of (1991-2020) from Wonju meteorological station and projected climate change scenarios (2021-2100) of the Representative Concentration Pathways models (RCPs). expected results confirmed the frequency of extreme agricultural drought in the future projected to increase under all studied RCPs. at present 100 years drought is anticipated to happen since the result showing under RCP2.6 will occur every 24 years, RCP4.5 every 17 years, and RCPs8.5 every 7 years, and it would be double in the largest warming scenarios. On another side, the result shows unsupportable water management, could cause devastating consequences in both food production and water supply in extreme events. Because significant increases in the drought magnitude and severity like to be initiate at different time scales for each drought indicator. Based on the expected result that the evaluating the impacts of extreme agricultural droughts and recession could be used for the development of proactive drought risk management, policies for future water balance, prioritize sustainable strengthening and mitigation strategies.

• Journal of Agricultural Extension & Community Development
• /
• v.12 no.1
• /
• pp.109-118
• /
• 2005

This study was carried out to identify the major characteristics of plug seedling farm's management. Thirty glasshouse farms were surveyed out of 42 farms that adopted plug seedling production technology in Korea. The major objectives of this survey were to determine the technical capability of the glasshouse farmers, and to analyze the significant differences in terms of production performance and management capabilities. The major results of the survey were as follows : 1) The production quantity of plug seedlings of the superior group was 43% higher than the inferior group. 2) The plug seedling loss rate of the superior roup was lower by 4% than the inferior group. 3) The income of superior group was 4.2 million Won per $1,000m^2$, while the income of the inferior group was only 0.45 million Won. 4) The cause of low production of grafted plug seedlings was primarily due to the lack of technical knowledge and skills. 5) The results indicated that the technical knowledge level and production skills of grafting plug seedling should be improved.

• Journal of Agricultural Extension & Community Development
• /
• v.7 no.1
• /
• pp.3-12
• /
• 2000

Agricultural extension services in Korea began in 1956, and led self sufficiency of rice through the 'Green Revolution' in 1970's, and a year around supply of green vegetables through the 'White/Vinyl Revolution' in 1980s. The developmental stages of agricultural extension services in Korea, in terms of major purposes, observed by the researcher were as follows; 1) Stage of production guidance when increase in production was directly related to increased income of farmers, 2) Stage of management guidance, when agricultural extension were not only concerned in increasing production, but also in management and marketing, and 3) Stage of improved welfare, when extension services put more emphasis on welfare of farmers in terms of quality of life, as well as increased production, management and marketing. Since late 1980s, farmers in Korea realized the fact that increased production may not lead to increased income. because of this, farmers also wanted improvement of management and marketing. Extension changed the identified needs of farmers to new knowledge, information, and technology in their farm business operation including management and marketing. Loosened cooperations among the central, provincial and local levels after localization of extension services since January 1997 should be strengthened. Provincial level monitoring and supervising should be enhanced for more effective agricultural extension services to meet the changing needs of farmers in the future.

• Korean Journal of Organic Agriculture
• /
• v.26 no.1
• /
• pp.1-17
• /
• 2018

This study analyzes the management performance of environmentally-friendly rice farms using GCM method based on the multifaceted approach. This approach compares the management performance of GCM farms before and after the introduction of GCM, as well as the performance of GCM farms with the performance of conventional farms. It also compares the technical and managerial competence level of surveyed GCM farms with that of conventional farms based on the standard diagnosis table developed by Rural Development Adminstration. Results showed that average income has increased after the introduction of the GCM method and the average income of GCM farms was higher than that of conventional farms, while the level of rice production in farms using GCM method was lower than that of conventional farms. In addition, the technical and managerial competence score of surveyed farms using GCM method was higher than that of conventional farms. These results implies that the higher management performance of GCM farms compared to the conventional farms is attributed to not only the GCM method but also the competence level of farms using GCM method.

• Korean Journal of Organic Agriculture
• /
• v.28 no.4
• /
• pp.555-577
• /
• 2020

This study analyzes the management performance and productivity of environmentfriendly farms compared to conventional farms and the trend of changes in price premium rates of environment-friendly agricultural products. And environmentfriendly farms in Jeollanam-do are surveyed for difficulties in management, proper premium rate of environment-friendly agricultural products (WTA), and tasks for promoting sales. According to the analysis results, the management performance and productivity of are low in many items, and the number of items that are on the decline or stagnant in the environment-friendly premium is making it difficult for farmers to manage. According to a farm survey, the most important task is to promote school meals for boosting sales of environment-friendly agricultural products. And 65.5% of the respondents having contract cultivation, nearly half or 41.1% of the respondents said they do not need contract cultivation or want contract cultivation for less than one year, which means that the current contract does not meet the needs of farmers. Finally, the environment-friendly premium rate based on consumer prices is generally lower than the premium rate (WTA) that farmers perceive as appropriate, so it is important to resolve the gap between the actual premium rate and the WTA.

• Korean Journal of Organic Agriculture
• /
• v.9 no.3
• /
• pp.45-71
• /
• 2001

The duck-rice forming system is increasingly spread up throughout Korea since 1992. It is discussed the rice field, rice quality, weed and pest management in the duck-rice weeding system compared to conventional farming system. Moreover the optimizing duck population, system management and fertilizer application rate were reported. Energy input and output by duck-rice farming system were carefully compared with those of low input sustainable paddy field and conventional farming paddy field. To find out the environmentally sound function of duck-rice system, the total nitrogen in paddy soil and paddy water, and nitrogen cycle in paddy rice cultivation system were analysed. finally the input and output were calculated, and ecological characteristic were determined in terms of nitrogen balance, labor input, animal input, renewable energy input, turnover of soil organic matter, energy loss, non-renewable indirect and direct energy input. It was concluded duck-rice weeding system could be recommended in terms of net only environmentally sound, but also farmer's income. But there are still some research needs for successful adaption of duck-rice farming to investigate to determine the optimal population of duck in rice paddy field unit, release time of duckling, duck management after release, and strategy for duck marketing and duck processing.

• Korean Journal of Environmental Agriculture
• /
• v.36 no.2
• /
• pp.119-128
• /
• 2017

BACKGROUND: Miscellaneous cereal have been largely consumed in Korea as due to their physiological functions beneficial to human health. The cereals are currently a social concern because they have been found to contain heavy metals. Thus, monitoring heavy metals in the cereals is an important requirement for food safety analysis. In this study, we determined arsenic concentration in the cereals randomly harvested from different markets. METHODS AND RESULTS: Inorganic arsenic was determined by ICP-MS coupled with HPLC system. The HPLC-ICP-MS analysis was optimized based on the limit of detection and recover test to reach $0.13-1.24{\mu}g/kg$ and 94.3-102.1%, respectively. The concentrations of inorganic arsenic equivalent to daily exposure were levels of $19.91{\mu}g/day$ in mixed grain, $1.07{\mu}g/day$ in glutinous rice, $0.77{\mu}g/day$ in black brown rice, $0.13{\mu}g/day$ in barley and $0.11{\mu}g/day$ in soybeans. CONCLUSION: The levels of arsenic in miscellaneous cereals were found lower than the recommended The Joint FAO/WHO Expert Committee on Food Additives (JECFA) levels, suggesting that the cereals marketed in Korea are not potential concern in risk assessment.

• Korean Journal of Environmental Agriculture
• /
• v.19 no.3
• /
• pp.201-205
• /
• 2000

Eleven runoff $plots(3{\times}15\;m)$ were built on a sloping field of a high plateau in Kangwon Province, Korea. The plots were treated with different tillage, residue covers and fertilizers, corn and potato were cultivated, and sediment discharge was measured from the plots for 3 years. Agricultural management practices were monitored around the plots to develop adequate best management practices. The least sediment occurred from the plots with no-till and 100% residue cover $(corn,\;0.1{\sim}2.2\;t/ha/year)$ and with contour tillage and vinyl sheet cover plots $(potato,\;0.1{\sim}0.2\;t/ha/year)$. The largest sediment was measured from the plots with up-and-down till and no cover ($11{\sim}33$ and $16{\sim}31\;t/ha/year$ from corn and potato plots, respectively). The type of organic and commercial fertilizers seemed not to affect sediment discharge. Sediment discharge from contour plots were largely dependent on the collapse of ridges due to the flush of water stored in furrows. The sediment discharge from contour corn and potato plots with no residue cover was $10{\sim}27$ and $16{\sim}24\;t/ha/year$, respectively. No-till with residue cover, vinyl cover for tuber crops, construction of furrow dam, frost heave research, furrow and ridge tillage with furrow dam after tuber crop harvest, limited stalk harvest of row crops, use of winter cover crops, and other common best management practices were recommended to minimize the sediment discharge from a high plateau sloping land culture.

• The Plant Pathology Journal
• /
• v.32 no.6
• /
• pp.570-574
• /
• 2016

Botrytis cinerea is a necrotrophic pathogen causing a major problem in the export and post-harvest of strawberries. Inappropriate use of fungicides leads to resistance among fungal pathogens. Therefore, it is necessary to evaluate the sensitivity of B. cinerea to various classes of fungicide and to determine the effectiveness of different concentrations of commonly used fungicides. We thus evaluated the effectiveness of six classes of fungicide in inhibiting the growth and development of this pathogen, namely, fludioxonil, iprodione, pyrimethanil, tebuconazole, fenpyrazamine, and boscalid. Fludioxonil was the most effective ($EC_{50}$ < $0.1{\mu}g/ml$), and pyrimethanil was the least effective ($EC_{50}=50{\mu}g/ml$), at inhibiting the mycelial growth of B. cinerea. Fenpyrazamine and pyrimethanil showed relatively low effectiveness in inhibiting the germination and conidial production of B. cinerea. Our results are useful for the management of B. cinerea and as a basis for monitoring the sensitivity of B. cinerea strains to fungicides.