본 연구는 향기가 강한 장미를 선발하고 이화학적 향기 특성 을 평가하기 위해 수행되었다. 향기가 있는 장미 라인의 꽃 향기 는 향분석기와 MOS타입 전자코를 이용하여 향 강도와 패턴을 조사하였다. 향기 분석 결과, 장미 라인들 중 ‘RosaScentNIHHS1’ 이 가장 높은 향 강도를 나타냈으며, 전자코 데이터의 주성분분 석(PCA)과 판별함수분석(DFA) 결과, 다른 계통과 뚜렷이 구분 되는 향기 패턴을 보였다. 또한 ‘RosaScentNIHHS1’과 모부본 품종인 ‘위스퍼’ 꽃잎의 휘발성 화합물을 헤드스페이스-고체상미 세추출법(HS-SPME)과 가스크로마토그래피-질량분석기(GC-MS) 를 이용하여 분석하였다. ‘RosaScentNIHHS1’의 주요 휘발성 화합물은 3,5-dimethoxytoluene, citronellol, geraniol이었 으며, 모부본 품종 ‘위스퍼’의 주요 화합물은 3,5-dimethoxytoluene 및 cis-3-hexenyl acetate, 4-vinyl anisole이었다. 두 계통 은 화합물 조성과 각 성분의 상대 성분비에서 상당한 차이를 나타냈다. 본 연구 결과는 향기 특성을 기반으로 한 천연 화훼 자원 개발을 위한 기초 자료로 활용될 수 있을 것이다.

This study evaluated the insect growth regulator pyriproxyfen (PPF) for its inhibitory effects on the adult emergence of fly (Musca domestica) and mosquito (Culex pipiens) larvae. Laboratory bioassays with a product containing 0.5% PPF were conducted using diet incorporation for fly larvae and water immersion for mosquito larvae at concentrations of 80, 160, and 320 mg/kg (flies) or mg/L (mosquitoes). PPF treatment reduced adult emergence in a dose-dependent manner. At 160 mg/kg (or mg/L), corrected adult emergence inhibition rates exceeded 80%, which meets regulatory thresholds for efficacy. Residual activity tests demonstrated sustained effects, with fly larvae showing 70% inhibition and mosquito larvae complete suppression (100%) at 45 days post-treatment. These findings confirm that PPF effectively disrupts metamorphosis of both species, with particularly strong and prolonged effects against mosquitoes.

The distinctive surface characteristics of two-dimensional(2D) materials present a significant challenge when developing heterostructures for electronic or optoelectronic devices. In this study, we present a method for fabricating top-gate graphene field-effect transistors (FETs) by incorporating a metal interlayer between the dielectric and graphene. The deposition of an ultrathin Ti layer facilitates the formation of a uniform HfO₂ layer on the graphene surface via atomic layer deposition (ALD). During the ALD process, the Ti layer oxidizes to TiO₂, which has a negligible impact on the current flow along the graphene channel. The mobility of graphene in the FET was enhanced in relation to the SiO₂-based back-gate FET by modifying the thin HfO₂ top-gate dielectric deposited on the Ti interlayer. Furthermore, shifts in the Dirac point and subthreshold swing were markedly reduced owing to the reduction in charge scattering caused by the presence of trap sites at the interface between graphene and SiO₂. This route to modulating the interface between 2D material-based heterostructures will provide an opportunity to improve the performance and stability of 2D electronics and optoelectronics.

This study investigated the flowering response of three Korean native Aster species, namely A. hayatae, A. spathulifolius, and A. koraiensis, to varying photoperiods. Three-month-old plants propagated from cuttings were grown under four different photoperiods: 9, 12, 14, and 16 h. Aster hayatae flowered under all conditions, with flowering rates of 92%, 85%, 65%, and 27% under 9-, 12-, 14-, and 16-h photoperiods, respectively. Flowering in A. hayatae was promoted by shorter photoperiods, classifying it as a facultative short-day plant. Aster spathulifolius flowered only under 9- and 12-h photoperiods, with no significant difference between these treatments, suggesting that the species is an obligate short-day plant. However, given the low A. spathulifolius flowering rates of 27% and 13% under 9- and 12-h photoperiods, respectively, further research is required. Aster koraiensis did not flower under any photoperiod, possibly due to vernalization requirements or juvenility. These findings offer valuable insights into the photoperiodic flowering responses of these three Korean native Aster species, enhancing our understanding of their ecological traits and potential horticultural applications.

국내 원예작물에서 화분매개곤충의 의존도는 해마다 증가하고 있다. 우리는 사과, 딸기 등 화분매개곤충의 의존도가 높은 주요 과수와 시설작물에 대하여 화분매개곤충의 사용기술을 개발하고 이를 현장에 적용하는 연구를 수행하고 있다. 2021년부터 2022년까지 딸기, 키위 등 5가지 주요 농작물에서 화분매개벌을 적용한 결과, 딸기에서 뒤영벌의 적용결과 기존 꿀벌과 통계적으로 같은 수준의 화분매개효과를 나타내었으며, 하우스에서 농약적용시 하우스 밖으로 벌통을 위치시키는 것이 방치보다 벌의 소실을 20% 더 감소시킬 수 있었다. 인공수분 에 의존하고 있는 씨없는 수박에서 수분수 식재와 꿀벌을 이용함으로 기존 벌 방사보다 16% 착과율을 향상시킬 수 있었다. 시설고추에서 꿀벌과 뒤영벌의 혼합사용시 기존 꿀벌 방사보다 고추 수량이 10% 향상되었고, 토마토 에서 660㎡당 뒤영벌의 봉군량을 1.5배 증가시 토마토 수량은 4.4% 향상되었다. 키위는 꿀벌로 기존의 인공수분 을 충분히 대체할 수 있었고, 인건비가 60%이상 절감되었다. 또한 현재 시판중인 30종의 살충제와 27종의 살균제 에 대하여 24시간내 반수치사를 보인 농약은 각각 살충제 6종와 살균제 4종 이었다. 이어서 2023년부터 참외, 멜론, 사과, 단감에 대한 현장적용연구가 진행되고 있다.

Bee traffic at the hive entrance can be used as an important indicator of foraging activity. We investigated patterns of honeybees and bumblebees near their hives as a basis for calculating bee traffic using the image deep learning. The flight pattern near the hive differed significantly according to bee at entering and leaving the hive. Honeybees mainly showed flight that changed flight direction more than once (69.5%), whereas bumblebees mainly performed straight flight (48.7%) or had a single turn (36.5%) in flight. When bees entered the hive, honeybees primarily showed one-turn or two-turn flight patterns(88.5%), and bumblebees showed a one-turn flight pattern (48.0%). In contrast, when leaving the hive, honeybees primarily showed a straight flight pattern (63.0%), and bumblebees primarily showed a straight or one-turn pattern (90.5%). There was a significant difference in flight speed according to the flight pattern. The speed of straight flight (0.89±0.47 m/s) was 1.5 to 2.1 times faster than flight where direction changed. Therefore, our results can help determine the capturing and recognizing the flying image of bees when calculating bee traffic by image deep learning.

Pyrethroid resistance in cockroach populations has been a public health challenge since the 1950s. The pyrethroid resistance in the German cockroach, Blattella germanica, is primarily attributed to knockdown resistance (kdr) mutations (E434K, C764R, and L993F) in the voltage-sensitive sodium channel gene (vssc). In this study, the pyrethroid resistance state of the German cockroach in the Republic of Korea (ROK) was assessed by analyzing the frequencies of kdr mutations using one-step PCR with total RNA. The results revealed that among the 25 populations examined, 14 populations exhibited the L993F kdr mutation, while no other mutations were detected. Since other cockroach species are also commonly found in human dwellings in ROK, the vssc genes were cloned from four other species, including Blattella nipponica, Periplaneta americana, Periplaneta japonica, and Periplaneta fuliginosa. Based on the genomic DNA (gDNA) sequences obtained from the vssc cloning, primer sets were designed to amplify the vssc fragment spanning the L993F mutation for each species and used to monitor the development of pyrethroid resistance in cockroach populations in the ROK. The study will facilitate the implementation of a nationwide monitoring program to assess cockroach resistance and select suitable alternatives.

This study examined the subacute oral toxicity of Dendropanax morbiferus H.Lév leaves hot-water extracts (DMWE) using male and female Spargue-Dawley rats. Rats were orally administered the DMWE at dose levels of 0, 250, 500, 1,000, and 2,000 mg/kg body weight (BW) for four weeks. For experimental period, clinical signs and the number of deaths were examined, and feed intake and BW of all experimental animals were measured once a week for four weeks. At the end of the experiment, blood samples were collected from all rats, and all animals were euthanized and autopsies were performed to collect major organs. No dead animals were found during the experimental period. In addition, no differences were found between control and DMWE-treated groups in feed intakes, BW changes, organ weights, clinical signs, hematological parameters, and serum biochemical parameters. The results of this study provided evidence that oral administration of DMWE at the dose of 2,000 mg/kg BW is safe in rats and may not exert severe toxic effects.

In this study, the acute toxicity of Dendropanax morbiferus H.Lév leaf hot-water extracts (DMWE) was examined in male and female ICR mice. Mice were orally administered the DMWE at dose levels of 0, 250, 500, 1,000 and 2,000 mg/kg body weight (BW) for single-dose toxicity test. There were no significant differences in change of BW between control and all DMWE treated-groups. In hematological and blood biochemical analysis, none of the parameters were affected by the DMWE. Similarly, there were no significant effects on markers for liver and kidney functions in all DMWE treated-groups. Since there were no adverse effects of the DMWE in single oral toxicity tests, even at the highest doses, it was concluded that the lethal dose 50 (LD50) of DMWE is estimated at > 2,000 mg/kg BW.