The alfalfa weevil (Hypera postica) is an important pest that causes significant damages to alfalfa crops, reducing yield and quality, but there’s a solution. This research had two main goals to evaluate the efficacy of insecticides available in Korea for alfalfa weevil control and to provide data for pest management studies. The experiment, conducted from 2023 to 2024 at the National Institute of Animal Science in Cheonan, Republic of Korea, included four treatment plots: control (CON), early-occurrence (EAR), mid-occurrence (MID), and late-occurrence (LAT). It also included two frequency plots with primary and secondary insecticide using 50% fenitrothion emulsion, which made it truly comprehensive study. The primary insecticide was applied at the first observation of the alfalfa weevil larvae, with subsequent secondary applications at specified intervals. The results showed that two-times insecticide applications significantly reduced larvae populations and increased yield and nutrient content compared to a single application. Specifically, control rates ranged from 94 to 94.7% on the third day after treatment and from 72.2 to 93.4% on the seventh day. Plots with two applications had higher yields and crude protein content. The study concluded that the timing and frequency of insecticide applications are critical to maximizing alfalfa yield and quality, emphasizing the importance of optimized application strategies for effective pest control.

This study aims to contribute to resolving the critical issue of weed management in newly established alfalfa fields, study has been conducted on effective herbicide use. The study evaluated the impact of various domestically available foliar herbicides on alfalfa phytotoxicity, weed control, yield, and nutritive value. The experiment was designed in a randomized complete block design with four treatments. Alfalfa ‘SW 5615’ seeded in the spring of 2024 on a 1 ha field (March 18), with herbicide treatments including fluazifop-P-butyl (FPB), bentazone (BEN), and a mixture of these herbicides (MIX). Herbicide efficacy, alfalfa yield, and nutritive value were assessed 30 days post-application. Results indicated that the MIX treatment achieved superior weed control comparable to hand weeding (HW), although it exhibited higher phytotoxicity, requiring extended recovery periods. While MIX led to lower overall yield, it enhanced alfalfa purity, resulting in higher crude protein (CP) content and relative feed value (RFV) compared to other treatments. The study concludes that despite the potential for increased phytotoxicity, mixed herbicide treatments could offer a strategic advantage in enhancing the quality of alfalfa feed through effective weed management, thereby improving CP and RFV, critical factors for the nutritional value of alfalfa. These findings provide valuable insights for optimizing weed management practices in alfalfa cultivation, suggesting that mixed herbicide application, although associated with increased phytotoxicity on the plants, could improve the overall feed quality by reducing weed competition.

한국에서 시설 딸기 해충을 방제하는 대표적인 방법은 살충제를 사용한 화학적 방법이다. 이는 농가에서 쉽게 접하고 처리 시기를 마음대로 조절할 수 있는 장점이 있지만, 방제 비용과 농업인부의 빈번한 화학살충제 노출이 큰 단점이다. 경주시 상평농원은 천적을 적극적으로 사용하는 농가로써 2020년부터 현재까지 4년간 4종의 천적 을 구매, 사육, 방사를 실시하였다. 방사한 천적은 점박이응애 방제용 칠레이리응애와 사막이리응애, 작은뿌리 파리 방제용 뿌리이리응애, 진딧물 방제용 콜레마니진딧벌이며, 농장의 규모는 재배동 1,250평, 육묘동 450평으 로 자가육묘를 하기에 1년 내내 딸기를 재배하는 농장이다. 본격적으로 천적을 활용하는 시기는 9월부터 이듬해 5월까지 약 9개월이다. 이 기간 동안 소요된 비용은 천적을 구매하고 자가사육하여 사용한 경우(154만원), 천적과 약제를 구매하여 같이 사용한 경우(240만원), 천적만 구매하여 사용한 경우(262만원), 약제만 처리(377만원) 순 으로 나타났다. 다만, 이 결과는 과학적으로 반복 및 재현 검증되지는 않았고, 각 농가의 천적과 해충의 생태에 대한 이해도와 작물 재배능력, 천적 사육능력에 따라 차이가 있을 수 있다.

This study was conducted to determine the appropriate seeding dates by verifying the difference in winter survival and productivity of alfalfa according to fall sowing dates in the central area of South Korea. The experiment was conducted for 2 years (2020 and 2021) at the field in the Department of Animal Resources Development, NIAS located in Cheonan. Sowing dates started from September 18 to November 8 with 10 days of intervals during 2020 and 2021; SO1 (September 18), SO2 (September 28), SO3 (October 8), SO4 (October 18), SO5 (October 28), and SO6 (November 8). After sowing, the winter survival rate was measured in the spring of the following year, and the dry matter yield was measured by harvesting at 10% flowering and harvesting five times a year. SO6 failed to winter survival, and SO5 also had a lower winter survival rate than SO1~4 (p<0.05). The average annual dry matter yield of alfalfa linearly decreased with delaying sowing dates (p<0.05). The feed value did not differ in the same year by delaying the sowing date in the same year. These results suggest that sowing date should be started before October 18 to increase winter survival and productivity of alfalfa in the central area of South Korea.

This study investigated the antioxidant characteristics of sweet potato according to different plant parts and drying methods. The sweet potato plant parts were divided into root tubers, stems, stalks, leaves, and tips, and the drying methods were freeze-drying and hot air drying. Total polyphenol and flavonoid contents and radical scavenging activity of the sweet potato plant parts were significantly different depending on the plant parts and drying methods. The total polyphenol content of freeze-dried sweet potato leaves and tips were 52.76 and 46.19 mg chlorogenic acid equivalents/g sample, and the total flavonoid contents were 222.47 and 214.12 mg quercetin equivalents/g sample, respectively, and decreased with hot air drying. DPPH radical scavenging activity was higher in freeze-drying than hot air drying and was significantly different depending on the plant parts. The ABTS radical scavenging activity of freeze-dried sweet potato leaves and tips were 43.48 and 44.68 mg Trolox equivalents/g sample, respectively, and decreased with hot air drying. Therefore, additional studies on the functionality of using by-products from sweet potato cultivation are needed.

Suncheon Bay Ecological Park, possessing abundant fisheries and biological diversity, was registered as a Ramsar wetland in Korea. Approximately 300 bacterial strains were isolated from the Suncheon Bay in a comprehensive study of indigenous prokaryotic species conducted during 2019-2020 in South Korea. A total of 12 bacterial strains were identified using 16S rRNA gene sequencing, demonstrating >98.7% sequence similarity with validly published species. These species were determined to be unrecorded bacterial species in Korea. A total of six strains were isolated from brackish water and Phragmites communis Trin (reed) species. These unrecorded species were phylogenetically diverse and belonged to three classes, six orders, and ten genera. Regarding the genus and class levels, the previously unrecorded species belonged to Jiella, Martelella, Rhizobium, Paracoccus, Rhodovulum, and Altererythrobacter of the class Alphaproteobacteria; Mycolicibacterium, Demequina, and Microbacterium of the class Actinobacteria; Confluentibacter of the class Flavobacteria. The twelve species were further characterized by gram staining, colony and cell morphology, biochemical properties, and phylogenetic position.

This study aimed to examine the changes in dry matter yield and growth characteristics of alfalfa (Medicago sativa L.) in response to variations in sowing dates during the autumn season of 2021-22 in a dry paddy field of Chilbo-myeon, Jeongeup-si, Jeollabuk-do. Treatments comprised four sowing dates at 10-day intervals, i.e., October 8, October 18, October 28, and November 8, 2021. The winter survival rate of alfalfa showed a significant difference between different treatments but was at a satisfactory level for all (p<0.05). The winter survival rate for the fourth sowing date, a month later than the first sowing date, was approximately 11.7% lower than that for the first sowing date. The plant height ranged between 82.3–93.1 cm and 60.5–63.7 cm at the first and second harvest, respectively, smaller at the second harvest than at the first harvest. The total dry matter yield of alfalfa was the highest at 13,316 kg/ha for the first sowing date, and the later the sowing date, the lower the dry matter yield. The protein content of alfalfa ranged between 13.6–17.3% in the first harvest, lower than the standard alfalfa protein content of 20% or more. In relative feed value, the first sowing (Oct. 8) was the most significantly higher in the first harvest (p<0.05). These results suggest that the early and mid-October sowing dates are optimum for sowing alfalfa during autumn and result in improved plant growth, dry matter yield, protein content, and winter survival compared to those at later sowing dates. Therefore, dry paddy fields can be safely employed for alfalfa cultivation with sowing dates in early and mid-October during autumn.

The background of the development is to contribute to the reduction of radioactive waste, recycling of resources and effectively purifying the air in the workplace. Ultimately, it affects the reduction of internal exposure of workers. According to the standard procedure of KHNP,「Use and Management of Respiratory Protection Equipment」, the expiration date of mask filter is indicated by the manufacturer before opening. It is 1 year from the date of first combination after opening. We have developed an air purifying equipment that can recycle and reuse expired mask filter waste in nuclear power plant. In order to confirm the performance, we observed air pollution level by operation time. The location was measured at 3 locations including the decontamination product warehouse in NPP, and the size of the measurement locations were 53 m3, 150 m3, 180 m3, and 900 m3. As a result of measurement, significant air purification effect was found in 53 m3 and 150 m3. Decontamination effect of 80% was shown after 1 hour of operation, and 20% of decontamination effect was shown gently for 3 hours thereafter. On the other hand, there was no significant decontamination effect in the 180 m3 and 900 m3 spaces. Significant results were derived by statistical methods. Statistical procedure involves the collection of data leading to test of the relationship between two statistical data sets, or a data set and synthetic data drawn from an idealized model. The basic composition and product characteristics was as follows: Blower, filter fixing unit, Air purifier outlet round shape, Differential pressure gauge, inverter (200 V, 3π, 200 W). The developed product weigh is 25 kg. This is lighter than the existing product weighing 100 kg. It is judged that it is suitable for convenient use. Because the area where the major air pollution level occurs is isolated by a room in NPP. This developed product has a greater significance in that it recycles radioactive waste within the radiation management area rather than air purification efficiency.

본 연구는 지역별로 수집한 유채 균핵병 균주에 대해 등록 된 3종의 약제를 사용하여 저항성 검정을 실시하였고, 저항성 발생 가능성이 있는 약제의 작용 기작과 관련한 유전자를 분석하여 변이 유무를 확인하였다. 1. Carbendazim-diethofencarb 약제배지의 경우, 0.1 ppm 농도에서 균사 생장 억제율은 13.3~41.9% 범위로 나타났으며, 1 ppm 이상의 농도에서는 모든 균주에서 96.1% 억제율을 보여 균주의 저항성이 확인되지 않았다. 2. Fludioxonil 약제배지는 0.1 ppm 농도에서 균사의 생장이 94.2% 이상 억제되었으며, 1 ppm 농도에서부터 100%의 억제 율을 보여 가장 약제 효과가 우수한 것으로 나타나 수집한 모든 균주에서 약제의 감수성을 확인하였다. 3. Boscalid 약제배지는 앞선 2종의 약제에 비해 균주의 균사 생장 억제가 뚜렷하지 않았다. 특히 10 ppm 농도에서 무안 수집 균주는 93.9%, 나주 수집 균주는 79.3%로 지역 간 차이가 있었으며, 1000 ppm의 높은 약제 농도에서도 균사의 생장을 100%까지 억제하지 못해 약제에 대한 균주의 저항성 발생 가능성을 추측하였다. 4. 3종의 시험 약제 농도별 균핵병 균주의 균사 생장을 50% 억제하는 농도(EC50)를 분석한 결과, Fludioxonil, Carbendazim-diethofencarb, Boscalid 약제순이었으며, 그 값은 각각 0.06, 0.16, 0.43 ppm으로 나타났다. 5. 또한, 3종의 시험 약제 농도별 발생한 균주의 균핵 형성 능력은 1 ppm 농도에서 Carbendazim-diethofencarb는 5.6개, Fludioxonil은 0개로 나타난 반면, Boscalid는 최대 11.3개의 균핵이 형성되어 차이를 확인할 수 있었다. 6. Boscalid 약제에 대한 균주의 저항성을 확인하기 위해 해당 약제의 작용 기작인 SDHI와 관련된 유전자 SdhB를 염기 서열 분석하였다. 염기서열 분석 결과 무안 및 부산에서 수집 한 균주의 경우 SdhB 표준 염기서열과 일치하여 감수성이었으나, 나주, 당진, 제주, 영암에서 수집한 균주는 32번째 염기 가 C→T로 치환되어 GCA(Alanine)→GTA(Valine) 점 돌연변이를 확인하였다.