• Journal of The Korean Society of Grassland and Forage Science
• /
• v.41 no.4
• /
• pp.223-233
• /
• 2021

The objective of this study was to investigate the effect of gypsum on the dry matter yield and the chemical composition of alfalfa in reclaimed tideland with soil dressing. The experimental site was Sukmoon reclaimed tideland. The tideland was reclaimed approximately 17 to 33 years ago and the 70 cm of soil was top-dressed. The soil that covers the reclaimed tideland brought from the island did not treat di-salinized. Treatments were consisted of three groups; control group where no gypsum (G0) was applied and two experimental groups where 2 ton/ha (G2) and 4 ton/ha (G4) of gypsum were applied, respectively. The first harvest was conducted when the alfalfa reached early flowering (open the flower 10%), and after that subsequent harvest was conducted at approximately 35 days intervals. The dry matter yield of the alfalfa showed that G2 was significantly higher in the first year than G0 and G4, and G2 tended to be higher in the second year than G0 and G4, although there were no significant differences between treatments. The reason for the high dry matter yield in G2 was that the soil pH and EC of the soil were at marginal and ideal levels and the coverage and alfalfa botanical composition were also high. In both years, there were no differences in the crude protein, neutral detergent fiber and acid detergent fiber contents and relative feed value between gypsum treatments. Meanwhile, the results in the first and second years showed that the alfalfa dry matter yield were negatively affected by droughts stress in spring and concentrated precipitation in summer. Therefore, this study suggests gypsum treatment in reclaimed tidal land could increase the dry matter yield of alfalfa, and 2 ton/ha of gypsum was the optimum rate.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.42 no.2
• /
• pp.89-95
• /
• 2022

This experiment was conducted to investigate the change in the productivity of Italian ryegrass seeds according to the inter-row spacing in the southern region of the Korean Peninsula. Italian ryegrass (Lolium multiflorum Lam.) 'Green Call' variety was sown in Jinju, Gyeongnam in the fall of 2020 with three inter-row spacings (20, 30 and 40 cm). The experiment was arranged a randomized block design with three replications. The ryegrass was sown on October 17, 2020, and the harvest was on May 31, about 60 days from the first heading stage. There was no difference among treatments with an average of April 27^th in heading stage. Plant height was significantly longer at 30 cm seeding interval and the shortest in 20 cm treatment. The length of the spike was the longest in the 40 cm seeding interval, and the number of seeds per spike was the highest in the 20cm seeding interval, but there was no significant difference among treatments. The seed yield was the highest at the 20 cm sowing interval (2,180 kg/ha), and decreased as the spacing increased. The dry matter content of seeds and straw was found to be 44.90% and 45.51% on average, and there was no significant difference among treatments. The amount of remaining straw after harvesting was found to be 7,506 kg/ha on average on DM basis, and was high at the 20 cm seeding interval. In view of the above results, it was found that it is most advantageous to sow at intervals of 20 cm when producing Italian ryegrass seeds through autumn sowing in the southern region.

• Journal of Bio-Environment Control
• /
• v.31 no.4
• /
• pp.343-355
• /
• 2022

This study investigated the consumption tendency and awareness of paprika in order to expand and promote the consumption of Capsicum annuum L. The research investigated the relationship of preference and loyalty based on emotional response of paprika according to the semantic differential scale. The survey was conducted from January to February 2022 using a random sampling method targeting 155 general people, and a total of 142 questionnaires were analyzed excluding 13 wrong answers. The nine items on the awareness of paprika showed to be consisted of three factors such as 'Food taste', 'Usability', and 'Economics' by factor analysis. Regarding to the awareness of paprika the positive answer that 'I think paprika is good for health' among the nine questions was the highest at 92.3%. In the preference aspect of shape, blocky type had the highest preference for the shape of paprika, followed by mini and conical types in order of preference (p < 0.001). As for color preference, yellow paprika was the most preferred, followed by orange, red, and green, showing statistical significance. The emotional response of paprika by paprika image showed a statistically significant difference in the four colors. The words such as 'bright', 'clean', and 'spirited' appeared as representative emotional vocabulary for paprika. Multiple regression analysis was performed to examine the effect of paprika on the three factors of awareness, preference, and loyalty due to the quality of life. As a result, the higher the paprika preference and quality of life, and the higher the taste and availability factors, the higher the paprika awareness and loyalty. As the variable that has the most influence on the loyalty of the survey respondents, preference was found to have the highest explanatory power at 43%. From these results, it was judged as a very important factor in the survey on the shape and color preference of paprika. Therefore, the recent increase in awareness that paprika is good for health is thought to act as a positive factor in revitalizing the domestic market and increasing consumption of paprika in the future. Also, among the three types of paprika, the yellow blunt type showed the highest preference. Therefore, in order to produce and promote this type of paprika, it is also important to increase the cultivation to suit the purchasing propensity of consumers.

• Journal of Bio-Environment Control
• /
• v.31 no.2
• /
• pp.79-89
• /
• 2022

With the wide use of greenhouses, the working hours have been increasing inside the greenhouse for workers. In the closed ventilated greenhouse, the internal environment has less affected to external weather during making a suitable temperature for crop growth. Greenhouse workers are exposed to organic dust including soil dust, pollen, pesticide residues, microorganisms during tillage process, soil grading, fertilizing, and harvesting operations. Therefore, the health status and working environment exposed to workers should be considered inside the greenhouse. It is necessary to secure basic data on particulate matter (PM) concentrations in order to set up dust reduction and health safety plans. To understand the PM concentration of working environment in greenhouse, the PM concnentrations were monitored in the cut-rose and Hallabong greenhouses in terms of PM size, working type, and working period. Compare to no-work (move) period, a significant increase in PM concentration was found during tillage operation in Hallabong greenhouse by 4.94 times on TSP (total suspended particle), 2.71 times on PM-10 (particle size of 10 ㎛ or larger), and 1.53 times on PM-2.5, respectively. During pruning operation in cut-rose greenhouse, TSP concentration was 7.4 times higher and PM-10 concentration was 3.2 times higher than during no-work period. As a result of analysis of PM contribution ratio by particle sizes, it was shown that PM-10 constitute the largest percentage. There was a significant difference in the PM concentration between work and no-work periods, and the concentration of PM during work was significant higher (p < 0.001). It was found that workers were generally exposed to a high level of dust concentration from 2.5 ㎛ to 35.15 ㎛ during tillage operation.

• Journal of Life Science
• /
• v.31 no.12
• /
• pp.1088-1093
• /
• 2021

Jeju horse (Equus ferus caballus) is a Korean horse breed that has been native to Jeju Island for a long time. Jeju horses are used as racehorses, and their racing ability is a major economic trait. The role of the myostatin (MSTN) gene in skeletal muscle mass has been studied in various mammals, and mutations in the MSTN gene are known to affect the racing ability and stamina of thoroughbreds. In this study, we compared the frequency of mutations in the MSTN gene in several horse breeds, including 1,433 Jeju horses. Among the mutations (ECA18 g.66493737C>T) in the MSTN gene, the long-distance aptitude genotype (TT) was found to have a frequency of 0.826 in Jeju horses, which was higher than that in Halla horses (0.285) and thoroughbreds (0.252). The genotypes and arrival records of Jeju horses were compared according to various distances (400 m, 800 m, 900 m, 1,000 m, 1,110 m, and 1,200 m). According to the results, the CT type showed a faster-reaching record than the TT type in races of less than 1,000 m. However, almost identical results were confirmed in races over 1,110 m. This study suggests that the MSTN mutation in Jeju horses may be related to race distance aptitude. In future research, the data in this study can be used for developing markers related to race distance aptitude and racing abilities in Jeju horses.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.24 no.3
• /
• pp.164-178
• /
• 2022

Uncertainties in weather forecasts would affect the reliability of yield prediction using crop models. The objective of this study was to compare uncertainty in crop yield prediction caused by the use of the weather forecast data. Daily weather data were produced at 10 km spatial resolution using W eather Research and Forecasting (W RF) model. The nearest neighbor method was used to downscale these data at the resolution of 5 km (W RF5K). Parameter-elevation Regressions on Independent Slopes Model (PRISM) was also applied to the WRF data to produce the weather data at the same resolution. W RF5K and PRISM data were used as inputs to the CROPGRO-SOYBEAN model to predict crop yield. The uncertainties of the gridded data were analyzed using cumulative growing degree days (CGDD) and cumulative solar radiation (CSRAD) during the soybean growing seasons for the crop of interest. The degree of agreement (DOA) statistics including structural similarity index were determined for the crop model outputs. Our results indicated that the DOA statistics for CGDD were correlated with that for the maturity dates predicted using WRF5K and PRISM data. Yield forecasts had small values of the DOA statistics when large spatial disagreement occured between maturity dates predicted using WRF5K and PRISM. These results suggest that the spatial uncertainties in temperature data would affect the reliability of the phenology and, as a result, yield predictions at a greater degree than those in solar radiation data. This merits further studies to assess the uncertainties of crop yield forecasts using a wide range of crop calendars.

• Journal of Mushroom
• /
• v.20 no.3
• /
• pp.168-172
• /
• 2022

This study was conducted to investigate the optimum supplementation ratio when replacing cotton seed meal with rapeseed meal for cultivating oyster mushrooms. The chemical properties among the treatments were pH 4.5~4.7, total carbon content was 46.3~46.5%, total nitrogen content was 1.6~1.7%, and carbon-nitrogen ratio was 27.0~27.8. These did not differ significantly from the control. Mycelial growth was 85.1 mm (Heuktari), and 72.8 mm (Suhan-1Ho) in medium containing 5% rapeseed meal, with no significant difference in mycelial density between cultivars. Fruiting body characteristics are as follows: In 'Heuktari', the color of the pileus was darker than control with an L value of 32.5, and pileus thickness and diameter were 3.2 mm and 27.6 mm, respectively. Stipe length and diameter were 86.0 mm and 9.1 mm, respectively. Valid stipe number per bottle (1,100 cc) was 25.9, and a yield of 189.7 g/1,100 cc was recorded in mixed medium containing 5% rapeseed meal (higher than control). In mixed medium containing 10% rapeseed meal, the yield was 184.5 g/1,100 cc (comparable to control). In 'Suhan-1Ho', supplemented with 5% rapeseed meal, pileus color was darker than control color, with an L value of 28.8. Pileus thickness was 4.5 mm. Stipe diameter was 12.3 mm (higher than control), and yield was 145.5 g/1,100 cc (comparable to control).

• Korean Journal of Environmental Agriculture
• /
• v.40 no.4
• /
• pp.279-289
• /
• 2021

BACKGROUND: Recently, the golden apple snail, Pomacea canaliculata has been used as an environmentally-friendly weed-control agent in rice farming. Although effective for this particular style of farming, P. canaliculata can be destructive to other crops. The objective of this study was to identify overwintering as well as regional and seasonal distribution characteristics of P. canaliculata. Notably, winter is typically fatal for P. canaliculata. However, owing to increasing average global temperatures, we assessed the ability of P. canaliculata to survive through uncharacteristically warm winters. METHODS AND RESULTS: To examine the distribution and overwintering regions of P. canaliculata, We conducted a survey from April 2020 to May 2021 on environmentally-friendly rice fields, agricultural waterways, and streams in 23 cities belonging to 8 provinces. In addition, because air temperature may influence the distribution density of P. canaliculata, we analyzed the winter temperature data (http://weather.rda.go.kr). CONCLUSION(S): In 2021, overwintering of P. canaliculata (1-3 individuals/m²) was observed in the Goheung and Yeongam regions in Jeonnam. Overwintering of P. canaliculata was observed in fewer regions in 2021 than in 2020; this fact may be attributed to the lower minimum temperatures measured in 2021 (approximately 8℃ lower) than those in 2020. Our results suggest that overwintering occurs as long as overnight temperatures are ≥ -15℃, but can take place if temperatures are as low as -19℃.

• Korean Journal of Environment and Ecology
• /
• v.36 no.3
• /
• pp.303-317
• /
• 2022

Climate change caused by increased greenhouse gas emissions can alter the natural ecosystem, including the pollination ecosystem and agricultural ecology, which are ecological interactions between potted insects and plants. Many studies have reported that populations of wild bees, including bees and wasps (BW), which are the key pollinators, have gradually declined due to climate change, leading to adverse impacts on overall biodiversity, ultimately with agribusinesses and the life cycle of flowering plants. Therefore, we could infer that the rising temperature in Korean Peninsula (South Korea) due to global warming has led to climate change and influenced the wild bee's ecosystem. In this study, we surveyed the distributional pattern of BW (Superfamily: Apoidea, Vespoidea, and Chrysidoidea) at 51 sites from 2017 (37 sites) to 2018 (14 sites) to examine the effects of climatic factors on the nationwide distribution of BW in South Korea. Previous literature has confirmed that their distribution according to forest climate zones is significantly correlated with mean and accumulative temperatures. Based on the result, we predicted the effects of future climate changes on the BW distribution that appeared throughout South Korea and the species that appeared in specific climate zones using Shared Socioeconomic Pathways (SSPs). The distributions of wild BW predicted by the SSP scenarios 2-4.5 and 5-8.5 according to the BIOMOD species distribution model revealed that common and endemic species will shift northward from the current habitat distribution by 2050 and 2100, respectively. Our study implies that climate change and its detrimental effect on the ecosystem is ongoing as the BW distribution in South Korea can change, causing the change in the ecosystem in the Korean Peninsula. Therefore, immediate efforts to mitigate greenhouse gas emissions are warranted. We hope the findings of this study can inspire further research on the effects of climate change on pollination services and serve as the reference for making agricultural policy and BW conservation strategy

• Journal of Bio-Environment Control
• /
• v.31 no.2
• /
• pp.133-141
• /
• 2022

Bulbophyllum auricomum Lindl. is a rare orchid and has flowers with an attractive fragrance. The present study investigated the tissue culture method for micropropagation. Capsules derived from artificial self-pollination were obtained for the best seed germination in MS basal medium. Plant growth regulators (1.0 mg·L^-1 of BAP and 2.0 mg·L^-1 of NAA) were affected by callus induction from subcultured pseudobulb explants. For the callus subculture, different natural plant extracts were tested in 11 treatment media. Among them, MS medium with 150 mL·L^-1 of coconut water was generally effective in fresh weight (1.75 ± 0.08) and (3.01 ± 0.20) of callus proliferation and PLBs induction at 1 and 2 months, respectively, followed by an MS combination of 30 g·L^-1 of banana and 20 g·L^-1 of potato extract. The results of a comparative study of different MS mediums containing plant growth regulators with a natural extract combination and MS medium supplemented with natural extract only showed that MS medium supplemented with a combination of natural extracts (150 mL·L^-1 of coconut water) and plant growth regulators (2.0 mg·L^-1 of BAP and 1.0 mg·L^-1 of NAA) obtained the highest shoot regeneration (3.37 ± 0.17) and (6.41 ± 0.68) after 1 month and 2 months of culturing, respectively.