The optimal determination of seeding rate is critical to minimizing uncertainties about the large variations observed in forage quality and productivity when alfalfa is cultivated under different geographical areas and growing conditions. The objective of this investigation was to provide information about the proper seeding rate according to harvest timing for alfalfa cultivation in the Northern regions of Korea. Alfalfa was sown in September 2018 at a seeding rate of 20, 30 or 40 kg/ha and harvested four times in 2019: May 3, July 2, September 11, and October 13. Regardless of seeding rate, alfalfa plant height was longest at the third harvest (113 cm) and the shortest in the last annual harvest (43.8 cm). However, seeding rate had no effect on alfalfa plant height at any harvest. Forage relative feed value was increased in the first cutting but decreased in the third cuttings as seeding rate increased. However, seeding rate had slight effect on alfalfa forage quality components at the second and fourth cuttings. Total annual DM and crude protein production (in 4 harvests) was greater at higher seeding rates. Plots seeded at a rate of 40 kg/ha produced on average 1,257 and 2,620 kg/ha more forage (DM basis) than those seeded at a rate of 30 or 20 kg/ha, respectively. Forage DM production at the first, second, third, and fourth harvests accounted for 36.1, 24.0, 27.1, and 12.8 % of total annual DM production, respectively. Overall, small differences were seen when alfalfa seeding rate was different but maximum forage DM production (in four harvests) was detected when seeding rate was 40 kg/ha. These data could be useful to the alfalfa growers by allowing them to make more accurate trade-offs between seed price and the expected magnitude of forage yield gains in order to select the best seeding rate.

Cutting management has been identified as a critical factor in the alfalfa production systems because it has a significant impact on maximizing yield and maintaining the forage quality. The objective of this experiment was to determine the proper cutting height according to harvesting time for optimizing nutrient yield and forage nutritive quality of alfalfa grown in alpine regions of Korea. Alfalfa was sown at a seeding rate of 30 kg/ha in August 2018 and harvested at four cuttings in 2019 (3 May, 2 July, 11 September, and 13 October). Cutting heights were adjusted at 5, 15, and 25 cm above the soil surface. Alfalfa plant was tallest at the third cutting (109 cm), which was on average 35 cm taller than the first or second cutting. Relative feed value (RFV) remained unaffected by cutting height at the first harvest, but increased consistently in subsequent harvests as cutting height increased. Alfalfa collected at the first and fourth cuttings had the highest RFV (mean 152), which was on average 8 and 67 units higher than the second and third harvests, respectively. At each harvest, in vitro dry matter digestibility was highest in alfalfa cut at a 25-cm height. Dry matter (DM) production at each cutting height was highest in the first cutting, accounting for on average 36-37% of total annual DM production, and lowest in the fourth harvest, accounting for about 11-13% of the total DM yield. The total dry matter production (in four harvests) was 4,218 kg/ha higher when alfalfa was subjected to a cutting height of 5 cm rather than 25 cm. Cutting height had no effect on total crude protein yield, but from the first to fourth cutting, the protein yield followed a decreasing trend. Finally, there were visible declines in forage nutritive quality when alfalfa was cut at a shorter height. However, the magnitude of difference in total forage yield may outweigh the slight decline in forage quality when alfalfa is cut at a lower height. The findings of this study could help the alfalfa growers make better harvest management decisions.

국립원예특작과학원에서는 2015년 거베라 신품종 ‘Red Velvet’ 을 육성하였다. ‘Red Velvet’은 2007년 10월부터 2008년 2월까지 주홍색 반겹꽃 스탠다드 거베라 ‘Rose’와 적색 반겹꽃 ‘Sabana’를 각각 모본과 부본으로 인공교배하여 얻은 187개체의 교배실생 분리집단으로부터 2008년부터 2015년까지 8년 동안의 개화 및 생육특성검정을 거쳐 선발된 절화용 스탠다드 거베라 품종이다. ‘Red Velvet’은 초세 강건한 갈색 화심의 적색(RHS R45B) 반겹꽃 대륜계통이다. 꽃의 평균 직경은 12.6±0.5cm이고, 내부설상화 및 통상화의 직경은 각각 5.7±0.3cm와 2.8±0.2cm이다. 꽃대는 꽃목직경이 상부 5.4±0.4mm, 중부 7.8±0.7mm 정도로 굵으며, 화경장은 60.0±8.1cm로 길다. 절화수명은 9.8±2.3일로 대조품종과 비슷하며, 연간 채화량은 48.3±4.8본/주로 많은 다수성 품종이다.

The purpose of this study was to investigate the quality and antioxidant properties of three fermented sweet potato cultivars (Shinyulmi, Hogammi, and Shinjami) using lactic acid bacteria. During the fermentation, the pH was lowered and the titratable acidity increased. The viable cell counts of lactic acid bacteria increased 8.44-9.62 log CFU/g. Organic acid content (especially lactic acid) of sweet potatoes increased by fermentation. Also, γ-Aminobutyric acid increased more than 8.6 times by fermentation in all samples. The total polyphenol and flavonoid contents of sweet potato, showed insignificant changes in all samples by fermentation. ABTS radical scavenging activity of all samples slightly decreased by fermentation, but not significantly. DPPH radical scavenging activity decreased slightly by fermentation except Shinyulmi. However, when compared with the varieties, Shinjami showed the highest activity. The reducing power of Shinjami decreased slightly by fermentation, but activity was the highest among all samples. Based on these results, most of the chemical properties and functionality of fermented sweet potato are retained after fermentation, although some antioxidant activity decreases. We suggest that three fermented sweet potato cultivars (Shinyulmi, Hogammi, and Shinjami) using lactic acid bacteria can be used in various applications because of their effective functional properties.

The bacterial diversity of an Antarctic hard coral, Errina fissurata, was examined by isolating bacterial colonies from crushed coral tissue and by sequencing their 16S rRNA gene. From the analyzed results, the bacteria were classified as Actinobacteria (56%), Firmicutes (35%) and Proteobacteria (9%). The thirty-four isolates were cultured in liquid media at different temperatures and their growth was assessed over time. The majority of the isolates displayed their highest growth rate at 25℃ during the first three days of cultivation, even though the coral was from a cold environment. Nevertheless, strains showing their highest growth rate at low temperatures (15℃ and 4℃) were also found. This study reports the composition of an Antarctic hard coral-associated culturable bacterial community and their growth behavior at different temperatures.

최근 다양한 유기재배 작물의 뿌리를 가해하는 굼벵이류의 피해가 증가하고 있으나, 굼벵이류는 토양 내 발생하는 특징으로 인해 발생시기 및 그 종류에 대한 확인이 어려운 해충이다. 피해를 끼치는 굼벵이의 발생을 파악하기 위해 고구마 유기재배지에 페로몬 트랩을 이용하여 굼벵이의 성충의 종류 및 발생 동향을 조사하였다. 조사지는 무안 유기재배농가와 국립농업과학원 완주군 포장에서 이루어졌다. 3종의 풍뎅이 페로몬 루어를 유인제로 사용하였으 며 6월 초부터 8월 말까지 조사지에 트랩을 설치하여 포획된 풍뎅이를 수집하여 동정을 하였다. 유기재배포장에서 포획된 종은 큰검정풍뎅이, 콩풍뎅이, 청동풍뎅이, 녹색콩풍뎅이, 별줄풍뎅이 등의 풍뎅이와 흰점박이꽃무지 등이 주로 채집되었다. 유기재배 고구마포장에서 풍뎅이 발생소장을 조사한 결과 최대로 발생한 시기는 7월초였다.

In order to investigate novel insect growth regulators (IGRs) from actinomycetes, 363 isolates of actinomycetes were tested for their IGR activities. Among them, Streptomyces sp. AN120537 showed the highest juvenile hormone antagonist (JHAN) activity and significant insecticidal activities against larvae of Aedes albopictus and Plutella xylostella. In addition, the dead larvae showed morphological deformities such as contraction of body segments or pigmentation of all body parts. Through liquid chromatography and bioassay-guided fractionation, 7 IGR compounds were identified from the crude hexane extract of AN120537. These results suggested that Streptomyces sp. AN120537 could be useful resources for development of eco-friendly insecticidal agents.

Japanese pine sawyer beetle, Monochamus alternatus Hope (Coleoptera: Cerambycidae) is considered as a serious pest in pine trees. To develop an eco-friendly strategy to manage this forest insect, we collected entomopathogenic fungi from Korean soil and assessed their virulence against the adults of the insect in laboratory conditions. As a result, two isolates with conidial suspension (1.0×107conidia/ml), showed 87% and 90% mortality 12 days after fungal treatment, respectively. We assessed the potential of the fungi-derived destruxin and protease as additives to the fungal isolates, and they showed insecticidal activity via feeding and spraying treatments. Finally, we produced fungal conidia in massive solid cultures and formulated wettable powders, and now studying optimal conditions of oil-based formulation with two isolates. Based on these results, we are evaluating the control efficacy of the fungal agents against M. alternatus in field conditions.

Oyster mushrooms are one of the most famous mushrooms for foods in Korea. ‘Santari’ developed on this study is P. pulmonarius of oyster mushroom species. ‘Santari’ is a new variety of oyster mushroom for the bottle culture. It was bred by mating with monokaryons isolated from ‘GMPO20404’ and ‘Hosan’. The optimum temperature for the mycelial growth was 26～29°C on PDA medium and that for the primordia formation and the growth of fruiting body of ‘Santari’ was 22°C and 20°C on sawdust media. It took 34 days to finish spawn running, 3 days to finish primordia formation, 3 days to finish fruitbody growth in the bottle culture. In the characteristics of fruit body, pilei were round type and brownish, stipe color was white and stipe shape was long and thick. The yield per bottle was 172g/1,100ml and was 43% higher than that of control variety(Hosan). As results of the physical properties of fruit body, springness, cohesive, gumminess and brittleness of stipe tissue were 87%, 82%, 193g and 16kg, respectively. The values of them are lower than those of control except cohesive.

Oyster mushrooms are one of the most famous mushrooms for foods in Korea. ‘Santari’ developed on this study is P. pulmonarius of oyster mushroom species. ‘Santari’ is a new variety of oyster mushroom for the bottle culture. It was bred by mating with monokaryons isolated from ‘GMPO20404’ and ‘Hosan’. The optimum temperature for the mycelial growth was 26~29°C on PDA medium and that for the primordia formation and the growth of fruiting body of ‘Santari’ was 22°C and 20°C on sawdust media. It took 34 days to finish spawn running, 3 days to finish primordia formation, 3 days to finish fruitbody growth in the bottle culture. In the characteristics of fruit body, pilei were round type and brownish, stipe color was white and stipe shape was long and thick. The yield per bottle was 172g/1,100ml and was 43% higher than that of control variety (Hosan). As results of the physical properties of fruit body, springness, cohesive, gumminess and brittleness of stipe tissue were 87%, 82%, 193g and 16kg, respectively. The values of them are lower than those of control except cohesive.

The purpose of this study was to investigate the complex ankle exercises on balance. 22 participants (male: 14, female: 8) with functional ankle instability were participated. Functional ankle instability was selected to be less than 24 points using the Cumberland ankle instability tool (CAIT) with people who had severe ankle sprain and then experiencing ankle giving way. A total of 20 minutes performed three times a week for four weeks with muscle strength and balance exercises. Muscle strengthening exercise was performed with Theraband, and balance exercise was performed with unstable support plates. Biodex balance systemⓇ was used to measure static and dynamic balance. The dynamic balance was selected in grade 2, 4, and 8. The static and dynamic balance (grade: 2, 4,and 8) balance was significantly decreased in anterior-posterior, and medial-lateral directions (p<.05). The instability was significantly increased after exercise (p<.05). These results suggest that complex exercises are beneficial to decreasing the functional ankle instability.

We present an optical imaging survey of AKARI Deep Field South (ADF-S) using the Korea Microlensing Telescope Network (KMTNet), to find optical counterparts of dusty star-forming galaxies. The ADF-S is a deep far-infrared imaging survey region with AKARI covering around 12 deg2, where the deep optical imaging data are not yet available. By utilizing the wide-field capability of the KMTNet telescopes (∼4 deg2), we obtain optical images in B, R and I bands for three regions. The target depth of images in B, R and I bands is 24 mag (AB) at 5, which enables us to detect most dusty star-forming galaxies discovered by AKARI in the ADF-S. Those optical datasets will be helpful to constrain optical spectral energy distributions as well as to identify rare types of dusty star-forming galaxies such as dustobscured galaxy, sub-millimeter galaxy at high redshift.