• The Korean Journal of Zoology
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• v.14 no.2
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• pp.57-74
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• 1971

The present investigation has been done to observe the ecological habits of field mice to protect the rice from damages during the growing season in paddy-field and during the storge period. The results obtained are summarized as follows: 1. Of 155 mice captured in the period of April-November 1970, which belong to four genera (Apodemus, Cricetulus, Rattus, and Micromys), 148 mice(95%) were found as striped field mice (Apodemus agrarius coreae). The population density of striped field mouse was revealed by the present study as 55/ha, which is quite a low level compared with that in Japan of 900/ha. 2. The age distribution of the mice as judged by their body weight was found mainly composed of adult and the sex ratio was found to be 1.8 as determined with 147 individuals. The nest was found to be occupied by an adult and was composed of at least three openings and more than one food storage tunnels. The mice usually keep hulled rice rather than unhulled one in storage tunnel. The weight of food found in a nest was about 50 grams on an average. 3. The mice show a most active behaviour 1-2 hours after the sunset, around midnight, and an hour before the sunrise, but they are active even in daytime in order for searching for food and for breeding. 4. The ratio (%) of damage appeared in high stem of sweet corn in August was 30 ~ 40 percent, whereas that in low stem was 80 ~ 90 percent. The weight of spoiled grains in paddy-field was 11, 400gm/0.4ha and this gives an estimate of 349, 695 for whole country. 5. The female striped field mouse weighs average of about 30 grams and gives birth to average of 4.8 younglings which wean away from female mouse three weeks after delivery. 6. The natural enemies to the mice are found to be carnivores (weasel, cat, mountain cat, fox, raccoon, and otter), raptatores(eagle, owl, kete, buzzard), and snakes. Two kinds of field rats(Rattus norvegicus, Cricetulus tritor) are also the predator to the mice. 7. The feeding preference of striped field mice follows in decreasing order of sweet corn, soybean, sweet potatoes, chestnut, and wheat. The mice do not have a preference for barley, millet, rough millet, red bean, and green bean. 8. The starvation experiment, in which water alone was supplied, revealed that the mice in good physical and nutritional conditions survived for 71 ~ 79 hours, whereas those in worse conditions survived for only 32 ~ 39 hours.

• Korean Journal of Poultry Science
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• v.50 no.3
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• pp.171-185
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• 2023

This study was conducted to investigate the effects of supplementation of Allium hookeri (AH) root powder on the gut microbiome, immunity, and health in broiler chickens fed experimental diets from d 10 to 28. A total of 60 10-day-old Ross 308 broilers were weighed and assigned to two dietary treatments with 5 birds per cage in a randomized complete block design based on body weight. The two experimental diets consisted of a control diet based on corn-soybean meal and the control diet supplemented with 0.3% AH root powder. All birds were fed ad libitum with experimental diets and water for 18 d. At 28 d, two birds near the median weight from each cage were selected for cecal content and small intestinal tissue sample collection. The addition of AH changed the gut microbiome by increasing probiotic candidate beneficial bacteria such as Enterococcaceae, Lactobacillaceae, Limosilactobacillus, Cuneatibacter, and Ruminoccoides. Regarding gut immunity, the supplementation of AH resulted in changes in intestinal immune cells, including reduced CD3+CD4+ T cells, which are a type of helper T cell, in the small intestine of birds (P=0.049). Additionally, there was a tendency to increase the expression of antioxidant function-related gene such as GPX2 (P=0.060), but no significant changes were observed in cytokines such as IL1b, IL6, and IL10. Overall, the addition of AH root powder may have positive effects on the microbiome of the chickens. This may help promote gut health in broiler chickens at the age of d 10 to 28.

• Korean Journal of Remote Sensing
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• v.39 no.5_1
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• pp.521-535
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• 2023

When converting rice fields into fields,sorghum (sorghum bicolor L. Moench) has excellent moisture resistance, enabling stable production along with soybeans. Therefore, it is a crop that is expected to improve the self-sufficiency rate of domestic food crops and solve the rice supply-demand imbalance problem. However, there is a lack of fundamental statistics,such as cultivation fields required for estimating yields, due to the traditional survey method, which takes a long time even with a large manpower. In this study, U-Net was applied to RGB images based on unmanned aerial vehicle to confirm the possibility of non-destructive segmentation of sorghum cultivation fields. RGB images were acquired on July 28, August 13, and August 25, 2022. On each image acquisition date, datasets were divided into 6,000 training datasets and 1,000 validation datasets with a size of 512 × 512 images. Classification models were developed based on three classes consisting of Sorghum fields(sorghum), rice and soybean fields(others), and non-agricultural fields(background), and two classes consisting of sorghum and non-sorghum (others+background). The classification accuracy of sorghum cultivation fields was higher than 0.91 in the three class-based models at all acquisition dates, but learning confusion occurred in the other classes in the August dataset. In contrast, the two-class-based model showed an accuracy of 0.95 or better in all classes, with stable learning on the August dataset. As a result, two class-based models in August will be advantageous for calculating the cultivation fields of sorghum.

• Journal of Plant Biotechnology
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• v.50
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• pp.275-289
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• 2023

Since the implementation of the Living Modified Organisms (LMOs) Act in 2008, approximately 10 million tons of genetically modified corn, soybean, potato, canola, and other crops have been imported into South Korea. The import approval procedures have been completed for approximately 191 cases that include seven crops. Of these, approximately 90 cases, excluding crossbreeds of approved LMOs, were reviewed via consultation risk evaluation in four areas: human health, crop culture, natural ecology, and marine fishery environment. LMO developers in South Korea, who are major stakeholders in the import of LMO crops produced overseas, have raised concerns regarding procedural inefficiency in consultation reviews and the need of excessive reviews that are unsuitable for food-feed processing purposes. These procedures reflect the perspective of consultation agencies that deviate from the nature of risk assessment and demand specific supplementary data that do not reflect familiarity and substantial equilibrium. Based on frequent instances of unintentional environmental release of LMO crops imported into Korea, the ministries responsible for consultation insist on a review that considers the climate and natural environment of Korea. In addition, the ministries mandate that their reviews reflect the expertise of competent ministries and are based on risk assessment principles and methods in accordance with international guidelines. In this regard, considering that traits introduced into LMO crops involving familiar agricultural crops have been considered safe for more than two decades, we have suggested reasonable alternatives to several risk assessment items for agricultural LMOs. These alternatives can mitigate conflicts of interest among key stakeholders within the scope of the current LMO regulations.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.69 no.1
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• pp.25-33
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• 2024

This experiment was conducted at the affiliated farm of the Suncheon University from 2022 to 2023 to investigate the growth, yield, and quality characteristics of soybeans based on the treatment method of Methyl Sulfony Methane (MSM) for the establishment of stable production practices. In the initial investigation of growth characteristics in 2022, an increasing trend in characteristics such as plant height, stem thickness, and branching index was observed as the treatment concentration increased from 50% to 200%. Yield components also followed the same trend, with the basal fertilization + top dressing 3 times at 200% treatment showing the highest yield at 355 kg·10a^-1, with the highest number of pods. In the subsequent study to determine the optimal concentration exceeding 200% in 2023, growth characteristics showed a trend of 400% > 200% > 800%. The basal fertilization + top dressing 3 times at 400% treatment exhibited the longest plant height (106.7 cm) and the most branches (6). In terms of seed quality, this treatment also had the highest proportion (66.9%) of seeds with a diameter over 6.7 mm. Additionally, in yield components such as pods, seeds per pod, and 100-seed weight, the basal fertilization + top dressing 3 times at 400% treatment showed the highest values, resulting in a maximum yield of 374 kg·10a^-1, representing a 23.4% increase compared to the control. Therefore, for the optimal production of high-quality soybeans, it is recommended to apply the treatment of basal fertilization + top dressing 3 times at 400% concentration, with top dressing occurring at 30-day intervals before harvest.

• Food Science and Preservation
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• v.30 no.6
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• pp.1056-1071
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• 2023

This study aimed to investigate the quality and microbial population changes for 90 days under two fermentation conditions, outdoors and indoors (35℃), with starters (single or mixed) in soybean paste. Bacillus velezensis NY12-2 (S1), Debaryomyces hansenii D5-P5 (S2), Enterococcus faecium N78-11 (S3), and their mixtures (M) were used for the makjang fermentation. The content of amino-type nitrogen among the makjang samples was highly shown in the indoors, followed by M, S3, and S2. The glutamic and aspartic acid contents in the M sample fermented in the indoors showed the highest values of 867.42±77.27 and 243.20±15.79 mg/g, respectively. By the electronic tongue analysis, the M sample fermented in the indoors exhibited lower saltiness and higher umami than the others. Consequently, we expect that using mixed strains, such as Bacillus, Debaryomyces, and Enterococcus, under constant conditions showed potential to the quality improvement of soy products.

• Journal of Life Science
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• v.34 no.1
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• pp.18-27
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• 2024

Laying hens are known to be able to 'bio-accumulate' the health-promoting ingredients of their diet into eggs. The purpose of this study was to characterize lignan-rich eggs as functional food fed with Schisandra fruit by-product (SCP). Experimental diets were formulated using yellow corn, rice bran, soybean meal, fish meal, meat bone meal, poultry meal, vitamin premix, mineral premix, CaCO₃, and supplemented Schisandra chinensis by-product. This experiment conducted a completely randomized design with 5 treatments for 5 laying hens. Levels of SCP were fed control diet or each formulated diet containing 1%, 3%, 5% and 7% SCP powder. The weight of eggs and the lignan content in white and yolk of egg were investigated every 7 days. Egg production and egg weight were not affected by diet at less than 5% SCP in the diet, but were significantly reduced when the diet was supplemented with a high concentration of 7% SCP after 3 weeks. Yolks and white in eggs were analyzed by using a high performance liquid chromatography (HPLC) to determine the lignans profile. Higher dietary SCP supplementation significantly increased gomisin N and schisandrin C in Acetonitrile (p<0.05). Gomisin N in egg white increased in a concentration-dependent manner, but shisandrin C not detected. These results indicated that the use of SCP powder in layering diets was effective in egg quality and for the production of lignans fortified eggs. In conclusion, dietary supplementation of Schisandra by-product with less than 5% can produce lignans-enrich eggs used as functional foods.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.4
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• pp.335-342
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• 2023

To achieve self-sufficiency in domestic wheat (Triticum aestivum L.), an increase in high-quality wheat production is essential. Given Korea's limited land area, the utilization of cropping systems is imperative. Wheat is compatible with a double cropping system along with rice, soybeans, and corn. Data on alterations in wheat quality following summer crop cultivation is required. This study investigated the impact of cultivating preceding crops such as rice, soybeans, and corn in a wheat cropping system. The analysis focused on the influence of these preceding crops on wheat growth, quality, and soil characteristics, elucidating their interrelationships and impacts. While there were no differences in growth timing and quantity during wheat growth, a significant variance was observed in stem length. Protein content, a key quality attribute of wheat, displayed variations based on the intercropped crops, with the highest increase observed in wheat cultivated after soybeans. Soil moisture content also exhibited variations depending on the intercropping system. The wheat-rice intercropping system, which requires soil moisture retention, resulted in greater pore space saturation in comparison to other systems. Moreover, soil chemical properties, specifically phosphorus and calcium levels, were influenced by intercropping. The highest reduction in soil phosphorus content occurred with soybean cultivation. These findings suggest that intercropping wheat with soybeans can potentially enhance wheat quality in domestic varieties.

• Korean Journal of Agricultural Science
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• v.15 no.1
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• pp.47-68
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• 1988

This study was conducted to define the optimal conditions for embryo growth during seed stratification and for breaking dormancy as well as seed germination of stratified ginseng seeds. The experiments were also carried out to detect some materials which were expected to induce seed dormancy in the ginseng seeds. The results summarized as follows; 1. The growth of embryo during seed stratification was significantly inhibited by the existence of endocarp. The fastest embryo growth was resulted at $15^{\circ}C$ and an estimated optimal temperature for embryo growth was about $18^{\circ}C$. 2. There was no significant difference between the embryo growth and germination ratio of ginseng seeds which were sown in seed bed at Aug-5 without seed stratification and that of artificial seed stratification. 3. Embryo growth and germination ratio was significantly inhibited by high temperature treatment at $30^{\circ}C$ for 24 hours or respiration stress by immersing seeds in water for 10 days or more. 4. When the seed stratification was started at $10^{\circ}C$, growth of embryo in the ginseng seeds were almost stopped. But, when the seeds were stratified first at $20^{\circ}C$ for 50 days and next at $10^{\circ}C$ for 50 days, the embryo growth was significantly promoted compared with the embryo growth in the seeds which were stratified at $20^{\circ}C$ for 100 days. 5. The successive embryo growth after seed stratification was significantly accelerated at $10^{\circ}C$ but the seeds chilled at $5^{\circ}C$ for 100 days were resulted in the highest germination ratio as well as the shortest days for germination. 6. The successive embryo growth during chilling treatment and seed germination were significantly inhibited by immersing seeds in water just before chilling treatment or during chilling treatment and by interruption of chilling treatment with raising temperature to $20^{\circ}C$ for 20 days during chilling treatment. 7. The germination ratio of ginseng seeds which finished chilling treatment was highest at $10^{\circ}C$ and 62.5% was the estimated soil moisture for the best germination of ginseng seeds. The ginseng seeds were found to require high amount of oxygen for germination. 8. Only water soluble material in homogenized ginseng seeds showed a significant inhibiting effect on the seed germination of sesame, millet and soybean. Water soluble material dissolved from undehisced ginseng seeds showed stronger inhibiting effect on the seedling growth of sesame than material from dehisced ginseng seeds. Extraction temperature did not influence the inhibiting effect of the material dissolved from ginseng seeds on the seedling growth of sesame. 9. Water soluble materials dissolved from the berry pulps, leaves, fresh roots and dried roots also showed a significant inhibiting effect on the seedling growth of sesame. 10. Water soluble materials dissolved from the ginseng seeds, leaves and fresh roots showed a significant inhibiting effect on the germination of true fungi and the growth of spawn but the growth of phytopathogenic bacteria was not. 11. Among the water soluble materials dissolved from ginseng seeds, the materials of low molecular weight less than 3,000 were resulted a significant inhibiting effect on the seedling growth of sesame and the materials of high molecular weight also showed an inhibiting effect.