Mosquitoes are medically important insect pests that act as vectors of various diseases when they feed on humans. Insect growth regulators (IGRs) could become an effective alternative to control mosquitoes because of their high specificity and relatively low toxicity to environment. Recently, we have developed high-throughput juvenile hormone antagonist (JHAN) screening system based on yeast-two hybrid assay. Actinomycetes have been reported to produce various bioactive compounds including insect growth regulators (IGRs). In this study, culture filtrates and mycelia extracts of 2,875 actinomycetes isolates screened for their IGR activities and mosquitocidal activities. Among 75 culture filtrates and 17 mycelia extracts with JHAN activities, 19 culture filtrate and 3 mycelia extracts showed high level of mosquitocidal activities against 3rd instar larvae of Aedes albopictus. These results suggested that secondary metabolites of actinomycetes could be used as environmentally benign mosquitocidal agents.

Japanese pine sawyer, Monochamus alternatus, is the main pest that mediates pine wilt nematode, Bursaphelenchus xylophilus, that causes serious damage to pine forests. In this study, we studied the strategy to control M. alternatus using entomopathogenic fungi. The fungi were collected from soil by an insect-baiting method and two fungal isolates (Metarhizium anisopliae JEF-197 and JEF-279) showed high virulence against M. alternatus. The Metarhizium isolates were evaluated for insecticidal activity against M. alternatus by spray treatment on live pine trees and wintering trees, and the M. anisopliae JEF-197 showed high insecticidal activity. In addition, the interaction of fungi and M. alternatus were analyzed by RNA-seq. This result can contribute to the development of insect control agents using entomopathogenic fungi.

Developmental characteristics of immature stages of Ostrinia scapulalis (Lepidoptera: Crambidae), which is a main insect pest against legume crops, were investigated at constant temperatures to prepare fundamental data for integrated pest management. Egg, larva and pupa could survive at temperatures from 16oC to 36oC. Developmental periods of those stages became shorter with increasing temperature between 16 and 31oC, 16 and 36oC, and 16 and 34oC, respectively. The lower developmental thresholds and degree-days(DD) were determined as 13.0oC and 56.9DD, 13.8oC and 277.5DD, and 14.2oC and 90.8DD using a linear regression model between temperature and development rate. Other parameters for explaining development of this species were estimated using a few non-linear models for developmental rate, distribution, and survivorship.

우리나라에서 흰등멸구는 매년 해외로부터 비래, 정착한 후 2~3세대를 경과하며 벼의 생육 및 품질 저하에 영향을 미치는 벼의 중요 해충 중 하나이며, 비래해충의 경우 비래 후 세대에 따른 변화 양상을 정확하게 예측하는 것은 방제시기와 방제수단을 결정하는데 중요하다. 공시충은 2018년 사육실에서(25±2 ℃, 60±5% RH, L:D=16:8) 누대사육하여 사용하였다. 흰등멸구가 국내에 비래 후 3세대까지 세대증식하면서 피해를 주는 것으로 가정하여 1세대와 3세대 간의 발육과 산란 등을 조사하였으며 얻어진 결과를 토대로 생명표를 작성하였다. 약충기간은 1세대와 3세대에서 각각 14.5일, 13.6일, 암컷 성충기간은 각각 17.2일, 11.8일로 나타났으며, 우화율은 98.3%, 85.0%로 조사되었 다. 산란기간은 각각 6.8일, 6.0일이었으며 산란수는 47.5마리, 122.6마리로 세대가 늘어나면서 증가하는 것으로 나타났다. 생명표 분석 결과, 순증가율, 내적자연증가율이 각각 5배, 1.7배 증가한 것으로 나타났다.

이리응애과의 많은 종들은 잎응애, 총채벌레 및 가루이와 같은 미소 해충의 생물학적 방제원으로 이용가능성이 높다. 실제로 칠레이리응애와 같은 포식활동이 왕성한 일부 종은 현재 농업에서 전세계적으로 많이 이용되고 있다. 특정 지역이나 생태계 또는 작물에 서식하는 이리응애과의 다양성 조사는 포식성 이리응애의 활용을 위한 좋은 기초자료가 된다. 그러나 국내에서 이와 관련된 자료는 90년대에 1건에 그쳐 자생 이리응애의 활용을 위한 후속 연구를 도모하기에 턱없이 부족한 실정이다. 본 연구에서는 중부지역의 6개도 17개 시군에서 2018년 7월부터 10월까지 자생 이리응애의 발생상황을 조사하였다. 그 결과 총 29과 57종의 식물종에 서식하는 20종의 이리응애를 확인하였다. 다양한 이리응애가 서식하는 식물종은 벚나무로 긴꼬리이리응애를 포함한 6종이 출현하였다. 서식 식물종이 가장 많은 이리응애는 긴꼬리이리응애로 17종이 식물에서 출현했고, 두 번째는 긴털이리응애로 16종의 식물에서 발견되었다.

Ostrinia scapulalis (Lepidoptera: Crambidae) overwinters as a final instar larva. In order to elucidate phenology of the insect, we studied several factors related to its overwintering. Neonate larvae from early August to early October entered overwintering through outdoor rearing. Pupation and adult emergence were observed during the periods from May to June, next year, and from May to July, respectively. Heat addition by 25oC to overwintering larvae induced shorter prepupal periods with progressing season. Supercooling points of overwintering larvae during the period from October to April were below -20oC, and those temperatures were significantly lower than those of a laboratory colony. It was estimated that higher content of glycerol in hemolymph is responsible for cold-hardiness as a cryoprotectant during overwintering.

거미는 산림 및 농작물 해충의 천적으로 알려져 있으며, 겨울철 벼 재배지에서 볏짚이나 논둑 등에 월동한다. 이 연구는 월동시기부터 모내기 전까지 유기 벼 재배지에 서식하는 거미상을 알아보기 위해 수행하였다. 거미의 발생을 조사하기 위해 함정트랩을 이용하였고, 농업과학원 유기재배포장에서 2018년 1월 중순부터 5월 중순까지 2주 간격으로 총 8회에 걸쳐 거미를 채집하였다. 조사가 이루어진 논은 거미가 월동 서식처로 이용할 수 있도록 볏짚을 걷어내지 않은 상태로 유지하였다. 조사 결과 6과 15종 359개체의 거미가 채집되었다. 그 중에서 애접시거미가 119개체(33%)로 가장 많았고, 들늑대거미(23%), 턱거미(17%), 각시긴손접시거미(8%) 순으로 나타났다. 또한 4월 중순(7회)에 가장 많은 개체가 채집되었고, 채집이 이루어질수록 거미의 개체수가 증가하는 경향을 보였다.

The Asian corn borer, Ostrinia furnacalis (Lepidoptera: Crambidae), produces final instar larvae of overwintering stage in response to decreasing day-length and temperature, and then those larvae pupate after about 6-8 month. In this study, we investigated a few properties related to cold hardiness during overwintering of the insect. Overwintering larvae collected in December could survive at least for 16 days at -20oC, while all larvae of a laboratory colony, which was reared at 25oC, 15L/9D, died within 2 hours. Supercooling points of overwintering larvae were below -20oC, and the temperatures were significantly lower than those (ca. -10oC) of the laboratory colony. It was estimated that higher content of hemolymph glycerol is responsible for cold-hardiness as a cryoprotectant during overwintering of O. furnacalis.

The serious emergence of chemical-mediated residual toxicity and insect resistance have been enforced the regulation of synthetic pesticides. Future decisions to select more realistic control options probably depend on the speed of technological development in chemical and biological pesticides. Now, a strategic collaboration between synthetic pesticides and biopesticides has been progressed, such as distribution and R&D in collaboration and M&A for obtaining microbial resources. Recently registered microbial pesticides are entomopathogenic fungi in pest management. A concept of e-biopesticide could be properly combined with digital agriculture and accelerate the use of biological control agents in the future farming.

프리지아 ‘Sweet Lemon’은 2007년 농촌진흥청 국립원예특작과학원에서 흰색 겹꽃 ‘Teresa’품종과 노랑색 반겹꽃 ‘Yvonne’ 품종을 교배하여 획득한 종자로부터 2007년 연노랑색 향기가 강한 겹꽃 프리지아 계통을 선발하여 품종으로 개발되었다. 2008년부터 2014년까지 개화 생육특성검정 및 육성계통평가회의 기호도 평가를 통해 선발되어 2015년 ‘Sweet Lemon’ 으로 명명되었다. ‘Sweet Lemon’은 연노랑색(RHS color chart Y2B) 겹꽃 프리지아 품종으로 화폭은 6.8cm이며 분지수는 6.7개로 다수확성 품종이다. 초장은 99cm로 초세가 강하며 대조품종 ‘Yvonne’ 91.7cm에 비해 34.7cm 더 크다. ‘Sweet Lemon’의 소화수 및 소화장은 각각 10.7개, 7.7cm로 ‘Yvonne’ 9.7개, 8.3이며 개화소요일수는 126일로 대비품종 보다 약 20일 정도 빠르다. 이 품종의 절화수명은 약 8.7일이며 자구번식력은 5.6배로 대조품종에 비해 우수하다. GC/MS를 이용한 향기분석 결과 총 58개의 방향성 화합물이 검출되었으며 주요성분은 linalool, alpha-Terpineol, alpha-Selinene, limonene이었다.

Ranunculus asiaticus characterizes colorful and attractive flower shapes that are related with the ornamental value of bulbous plants. Improving ornamental value of bulbous flowers has been the general goal of floricultural market. Gibberellic acid (GA3) and benzyladenine (BA) play an important role in growth and developmental processes in floriculture. Combinational treatments of these two hormones have been used in floriculture to improve flower quality. We assessed the effects of combined GA3 and BA, as well as the individual effects of each hormone, on growth characteristics using soil drench application to eight R. asiaticus cultivars, ‘Giallo Millepetali’, ‘Bianco Millepetali’, ‘Arancio Millepetali’, ‘Rosa SC’, ‘Arancio Pratolino’, ‘Giallo Pratolino’, ‘Bianco Pratolino’, and ‘Rosa Ch Pratolino’. GA3 treatments increased plant height and first flower size of R. asiaticus cultivars. Moreover, about 5 to 9 days to flowering were averagely shortened by GA3 treatments compared to controls. On the other hand, the opposites, including first flower size and days to flowering, were observed for cultivars treated with BA, compared with controls. Treatments of GA3 + BA generally affected growth traits, such as plant height, flower size, and the timing of flowering on some R. asiaticus cultivars. In particular, about 5 to 6 days to flowering were reduced on average by Treatments of GA3 + BA. Our results showed positive growth effects, including plant height, days to flowering, first flower height, number of flowers from the application of individual and combined hormones to R. asiaticus cultivars and demonstrate a role for these hormones in future bulbous floriculture.

본 연구는 Deci와 Ryan의 자기결정성이론을 바탕으로 게임사용 동기가 게임행동에 미치는 영향에 대해서 분석하였다. 게임사용 동기는 내재적 동기와 외재적 동기로 구분하였으며, 게임행동은 게임 선용과 게임과몰입으로 구분하였다. 분석을 위해 한국콘텐츠진흥원의 2016년 게임 과몰입 실태 조사의 자료 중 3,000명의 성인을 대상으로 실시한 온라인 조사의 자료를 활용하였다. 자료는 잠재변 수간의 관계를 알아볼 수 있는 구조방정식모형 분석방법을 통해 분석하였다. 분석은 Mplus 7.4 프 로그램을 활용하여 실시하였다. 본 연구의 결과는 다음과 같다. 첫째, 내재적 동기는 게임선용과 정적인 관계가 있었다. 둘째, 외재적 동기는 게임선용과 게임과몰입과 정적인 관계가 있었다. 게임과 몰입과의 관계의 효과크기가 게임선용과의 관계의 효과의 크기보다 세 배 이상 크게 나타났다. 본 연구는 한국사회에 만연한 게임에 대한 부정적인 인식에서 벗어나, 게임으로 인한 긍정적인 결과와 부정적인 결과에 대하여 균형 있는 접근을 시도하였다는 점에서 의의가 있다. 또한 자기결정성이론을 바탕으로 게임사용자와 게임제공자의 긍정적인 게임사용을 촉진하기 위한 시사점을 제시하였다.

This paper examines a simple one-step and catalyst-free method for synthesizing carbon nanoparticles from aliphatic alcohols and n-hexane with linear molecule formations by using a stable solution plasma process with a bipolar pulse and an external resistor. When the external resistor is adopted, it is observed that the current spikes are dramatically decreased, which induced production of a more stable discharge. Six aliphatic linear alcohols (methanol- hexanol) containing carbon with oxygen sources are studied as possible precursors for the massive production of carbon nanoparticles. Additional study is also carried out with the use of n-hexane containing many carbons without an oxygen source in order to enhance the formation of carbon nanoparticles and to eliminate unwanted oxygen effects. The obtained carbon nanoparticles are characterized with field emission-scanning electron microscopy, energy dispersive X-ray spectroscopy, and Raman spectroscopy. The results show that with increasing carbon ratios in alcohol content, the synthesis rate of carbon nanoparticles is increased, whereas the size of the carbon nanoparticles is decreased. Moreover, the degree of graphitization of the carbon nanoparticles synthesized from 1-hexanol and n-hexane with a high carbon (C)/oxygen (O) ratio and low or no oxygen is observed to be greater than that of the carbon nanoparticles synthesized from the corresponding materials with a low C/O ratio.

Polyphenol profiles, physicochemical properties, antioxidant activities, and inhibitory effect of adipocyte differentiation of Houttuynia cordata fermented with Lactobacillus brevis B84 were evaluated. Six polyphenols were characterized for this plant by using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), and the results were compared with total phenolic content by a spectrophotometric method. The total amount of the identified polyphenols was lower than that determined by the spectrophotometric method. However, the fermentation process influenced polyphenol composition such as content of vanillic acid and caffeic acid. The phytochemical profiles were evaluated by high-performance liquid chromatography with UV and electrospray ionization mass spectrometry detection (HPLC-DAD-ESI-MSn). Total sugar and reducing sugar contents decreased after fermentation. Antioxidant activities such as DPPH, ABTS, and superoxide anion radical scavenging and reducing power were evaluated to compare the beneficial effect after fermentation. Fermented H. cordata increased the lipolytic effect in 3T3-L1 adipocytes. Overall, the results indicate that the fermentation of H. cordata with L. brevis B84 produces changes of phenolic compounds, antioxidant activity, and lipolytic effect.