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.

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.

Biochar obtained from the thermal conversion of biomass has high potential as a substitute material for activated carbon and other carbon-based materials because it is economical, environmentally friendly, and carbon-neutral. The physicochemical properties of biochar can also be controlled by a range of activation methods such as physical, chemical, and hydrothermal treatments. Activated biochar can be used as a catalyst for the catalytic pyrolysis of a biomass and as an absorbent for the removal of heavy metal ions and atmospheric pollutants. The applications of biochar are also expanding not only as a key component in producing energy storage materials, such as supercapacitors, lithium ion batteries, and fuel cells, but also in carbon capture and storage. This paper reviews the recent progress on the activation of biochar and its diverse present and future applications.

The important PH (paleontological heritages) with scientific, educational and esthetic values designated as natural monuments and protected by legislations of South and North Koreas are herein compared for the first time. On the basis of data (Jan. 2017) provided by the Cultural Heritage Administration of (South) Korea, a total of 457 natural monuments was designated. Of these, geological heritages are 80 in number, which includes 24 (30%) PH. Data (Dec. 2005) of North Korea show that a total of 474 natural monuments was designated. Among these, geological and geographical ones are 154 in number, which includes 22 (14%) PH. Differences between PH of South and North Koreas are regarded to be directly related with geological difference in distribution of the fossil-bearing strata between South and North Koreas. PH of Silurian corals, Devonian plants, Jurassic fishes, Cretaceous dinosaur tracks, birds (so called Korean Archaeopteryx) and pterosaurs, and Pleistocene paleoanthropological fossils appear to be scientifically significant. Together with these North Korean PH, scientific, esthetic, conservational, educational, and economical values of important PH including KCDC (Korean Cretaceous Dinosaur Coast), Jigunsan Shale, and Geumgwangdong Shale of South Korea should be evaluated as potential future candidates for international heritages.

Lacticin NK34 is a small nisin-like bacteriocin present in the supernatants of an isolate of Lactococcus lactis from jeotgal, a salted and fermented Korean food made with seafood such as shrimp, oysters, and fish. Recently, we demonstrated that a partially purified NK34 is highly effective against various Staphylococcus species in a murine infection model. In this study, the two major bacterial pathogens associated with bovine mastitis, Streptococcus aureus and S. agalactiae, were evaluated for their susceptibility to NK34 in vitro using a standard teat-dip assay as well as in vivo using mastitic cows infected with one of these pathogenic strains. The experimental analyses showed a significant decrease (up to 98 times) in the bacterial numbers between the NK34-treated and -untreated teats. Moreover, a dramatic reduction in somatic cell counts was observed at 3 days post-treatment with 10 ml of NK34 administered directly into the mastitic cows. Neither S. aureus nor S. agalactiae were recovered. Taken together, these results imply that lacticin NK34 is an alternative antimicrobial substitute for the treatment of bovine mastitis, caused especially by either S. aureus or S. agalactiae.

A surveillance of chigger mites was conducted to clarify the incidence of scrub typhus vectors by new chigger mite collecting traps instead of trapping wild rodents for surveillance from each 4 collection points of 5 regions from September to November 2012 in Korea. During the surveillance period, 2,829 chiggers were collected and 10 species of 4 genera were identified. The first appearance of chigger mite and patients was 39 week (9.19~9.25) and the density of chigger mites had the peak in 43 week (10.17~10.23) and the density of patients had the peak in 44 week (10.24~10.30), respectively. In Goryeong-gun, a total of 1,797 mites representing 4 genera and 6 species were collected and the predominant species were Leptotrombidium scutellare (86.0%), L. pallidum (6.5%) and L. palpale (4.7%) whereas, In Gurye-gun, a total of 89 mites representing 2 genera and 3 species were collected and the predominant species were L. scutellare (46.5%) and L. palpale (36.2%) in similar to the natural environment. The high collecting rates were recorded at rice field (71.8%) and waterway (11.6%). This result shows that the surveillance of scrub typhus vectors by new chigger mite collecting trap is useful as an eco-friendly method.

Fermented soybean food is one of most economical and health food due to its valuable nutritional and medicinal attributes and have been consumed for centuries as flavoring ingredient in Korea. On fermented soybean food such as doenjang, aroma compounds are important property because they determine taste and grade of fermentation. This study investigated variety of aroma compounds of doenjang made from different soybean genotypes. Aroma compounds in twelve different doenjang made from two cultivar (Daewon and Taekwang) and ten elite lines were extracted by steam distillation extraction (SDE) method and analyzed by gas chromatography/mass spectrometry (GC/MS). Aroma compound were detected over 80 kinds in eight samples (Daewon, Taekwang, MY177, MY187, MY189, MY192, MY204 and MY205) and under 70 kinds in four samples (yeonchun1, MY188, MY203 and MY206). Among the detected aroma components, 47 compounds were assigned as aromatic compounds (21), long chain fatty acid (13), short chain fatty acid (5) and others (8) by the computer library (Wiley 7n program). The major aroma compounds in twelve different doenjang were benzaldehyde, benzeneacetaldehyde, 2-methoxy-4-vinylphenol, pyrazine type compounds, cysteaminesulfonic acid, palmitic acid, oleic acid and linoleic acid. Each doenjang made by same condition (microbe, temperature, aging time and etc) had a difference in ratio and variety of aroma compounds due to different components having soybean genotype.