Both Nilaparvata lugens Stål and Laodelphax striatellus Fallén has been known as the major rice pests which were irregularly migrated into Korea by wind current from China. We re-arranged and compared the resistance profiles to detect the existence convergent adaptation by using the previously published dataset (N. lugens at 2014, 17:711-716 and L. Striatellus at 2016, 19:247-252 in J. Asia Pac. Entomol., respectively). Both species commonly exhibited the high level of resistance to imidacloprids. Especially, the immigrant populations of L. Striatellus exhibited higher resistance level to indigenous populations, suggesting that they would settle down in Korea with insecticide resistance traits being predisposed. To detect the convergent adaptation to insecticide, pearson correlation analysis were employed by comparing mean dosage of LD50 and resistance ratio to nine insecticides. Strikingly, high and similar dosage responses were observed between the two species with high correlation coefficients of 0.928 (df=7, P <0.001) and 0.950 (df=7, P <0.001), respectively, in the comparison of LD50 vs. resistance ratio. This finding indicates that convergent adaption has occurred in both species through consistent selection by insecticides with similar usage patterns.

The Riptortus-Burkholderia symbiosis is a newly emerging insect-bacterium symbiotic system. This symbiosis system has a good merit as an experimental model system to produce the non-symbiotic (apo) and symbiotic (sym) host insect. In recent reported papers, the symbionts play important biological roles for the host insects. Meanwhile, juvenile hormone (JH) is one of major hormone synthesized corpora allata(CA) to control many physiology of insect. However, the study for cross-talk mechanism between symbionts and host hormones to control important physiological phenomenon of insects is almost none. In this study, we found that Riptortus speed up adult emerging and increase egg laying on presence of symbiont Burkholderia. Also we found that hexamerin proteins, which were controlled the expression by JH, were accumulated in sym-Riptortus hemolymph compare with apo-Riptortus. According as combined results, we hypothesized that the gut symbiont Burkholderia can control JH titer to conclude out beneficial effects such as development and reproduction of R. pedestris. To verify this hypothesis, we examined measurement of JH titer, expression of hexamerins as JH response genes and RNAi for hexamerin protein during whole Riptortus life on presence or absence of symbiont Burkholderia. All results demonstrated that gut symbiont controlled JH titer of Riptortus. Controlled JH amount by symbiont Burkholderia in host midgut regulated hexamerin protein expression for speeding up adult emerging and increasing egg production.

The bumblebee, Bombus terrestris, has played an important role as one of the alternative pollinators since the outbreak of honeybee collapse disorder. Recently, pathogens and parasites such as viruses, bacteria and mites, which affect the life span and fecundity of their host, have been discovered in B. terristris. In order to detect the microsporidian pathogen, Nosema Spp. in the field populations of B. terristris, we collected adults and isolated their genomic DNA for diagnostic PCR. The PCR primers specific for Nosema Spp. were newly designed and applied to gene amplification for cloning. Only small subunit ribosomal RNA(SSU rRNA) gene of N. ceranae was successfully amplified and sequenced among examined genes, which indicates that N. ceranae mainly infects the examined field population of B. terristris. To detect of SSU rRNA gene, two regions of SSU rRNA gene were selected by primary PCR analysis and further analyzed in quantitative real-time PCR(qRT-PCR). The qRT-PCR analysis demonstrated that SSU rRNA of N. ceranae was detected at concentrations as low as 0.85 ng/μl genomic DNA. This result suggests that the detection via qRT-PCR can be applied for the rapid and sensitive diagnosis of N. ceranae infection in the field population as well as risk assessment of B. terristris.

The first commercial bioinsecticide in Korea was registered in 2003 to control diamond back moth and beet armyworm in Chinese cabbage using Bacillus thuringiensis subsp. aizawai. Currently, fourteen microbial pesticides have registered in Korean market. The Korean government is aiming for 40% reduction (from the 2004 value) in the use of chemical pesticides by 2013. To increase the use of microbial pesticides as an alternative of chemicals, we conducted in vitro bioassay with Bt products. Bt products were treated alone and in combination against larvae of beet armyworm, diamond back moth and tobacco cutworm. Five Bt products shown high mortality against diamond back moth in recommended concentration, but had low control effects against beet armyworm and tobacco cutworm. Mixed Bt products had no synergic effects against the tested three moths. When Bt products were sprayed with higher concentration than recommended dose, those mortality was similar with lower concentration.

Scirtothrips dorsalis Hood is a newly advent pest on citrus in Jeju. Both larvae and adult attack the new shoots and young and matured fruits of citrus. S. dorsalis is highly polyphagous with over 100 recorded species, but not known in Jeju. As a result from investigating the host plants in and/or around citrus orchards in Jeju during 2009 to 2010, they were 25 families 39 species. The total thrips examined on those plants were 13 species, and the richness thrips among them was S. dorsalis, Frankliniella occidentalis, Thrips tabaci and Thrips hawaiiensis. The widespread host plants of S. dorsalis were Mallotus japonicus, Paederia scandens, Hedera rhombea, Cayratia japonica and Clematis apiifolia and they can be also used for monitoring plants. On early May, the larvae of S. dorsalis were first investigated on the shoots of Mallotus japonicus, Lonicera japonica, Paederia scandens, Viburnum awabukira, Fraxinus rhynchophylla and Celtis sinensis. The other thrips species except S. dorsalis and T. tabaci, especially F. intonsa, T. hawaiiensis, T. flavus and T. coloratus were just found on flower stalks during the blooming season.

The males of cryptic mealybug, Pseudococcus cryptus, were attracted on trap baited with or without a synthetic sex pheromone. The attractiveness of sex pheromone trap was higher than yellow-color sticky trap, but both phenologies were similar. There was a positive relationship between mean density of 2nd nymph to adult cryptic mealybug and the density of the male caught on trap. The density of cryptic mealybug per tree was higher correlated with yellow-color sticky trap than sex pheromone trap. The pattern of cryptic mealybug male occurrence had two to three cohorts in a generation resulted from overwintering stage. The maximum occurring time of 1st to 2nd nymph stage could be estimated from the peak time of trap catch by effective temperature accumulation. The higher and lower threshold temperature was estimated as 10.9 and 32.6℃, respectively and its thermal constant was 360 degree-day. The cryptic mealybug parasitoid, Anagyrus sp., which was first recovered in Jeju in 2009, was well attracted on yellow-color sticky trap. There was a high correlation between the density of Anagyrus sp. and of cryptic mealybug males caught on trap.

Strawberry, Fragaria ananassa Duchesne, is one of the important horticultural crops cultivated in greenhouses. Tetranychus urticae is one of major strawberry pests, and Neoseiulus californicus and Phytoseiulus persimilis have been used as biological control agents for control of T. urticae. The interactions between T. urticae and N. californicus and between T. urticae and P. persimilis were investigated to compare their control efficiency for T. urticae on a spatially-structured strawberry leaf disc area at different temperatures and on different treatments. The experimental arena was an array of leaf discs (3 cm diameter) placed upside down on a water-saturated cotton pad in an aluminum pan (17.4 x 21.5 cm). Twenty leaf discs (4 x 5) were placed adjacent each other for allowing dispersal of T. urticae and its predatory mites. The temperature conditions were 20, 25, and 30°C and there were six different treatments. The overall population densities of T. urticae were influenced by temperature (20, 25, and 30°C) in N. californicus treatment. In the same temperature condition, P.persimilis was more effective than N. californicus to control T. uritcae. Two predator systems were better than one predator systems to suppress the population density of T. urticae at 25°C. Some results of this study could be used to understand the spatial association of T. urticae and its predatory mites in greenhouse crops and fields.

The damage of citrus fruit by yellow tea thrips, Scirtothrips dorsalis Hood, was first confirmed in 2008, and has since been one of the serious pests of citrus in Jeju. This was reported on damage symptom on tangor cultivar, Setoka (Tangor Norin No. 8) fruits cultivated in a greenhouse and the characteristic of spatial disttribution of S. dorsalis caught on yellow sticky traps was conducted in three commercial citrus orchards. The feeding habits by S. dorsalis cause rind blemishes on the navel part of fruit. The damage is characterized by being scarped and figure like covered cloud on satsum mandarine fruit, but on by a brown ring of rough russeting that occurs on navel part of Setoka fruit. The season of damage occurrence was from middle of June to late of July. There was a highly significant relationship between the average number of thrips per trap and the maximum number caught on a trap. The overall differences between the linear regression models obtained from mean-variance relationship for each surveyed fields were tested by type Ⅲ error and contrast method. The characteristic of spatial distribution of S. dorsalis was better described by Taylor's power law than Iwao's patchiness regression, and the dispersion index which is the slope (=1.72) of linear regression model showed the aggregated distribution pattern. The sequential sampling stop lines at fixed precision level of 0.20, 0.25 and 0.30 were calculated.

Some responses of cryptic mealybug, Pseudococcus cryptus, for a sex pheromone, [(1R,3R)-3-isopropenyl-2,2-dimethylcyclobutyl]methyl 3-methyl-3-butenoate, were studied to develop the applying strategy of sex pheromone trap for efficient monitoring and control-time decision in citrus orchards grown in greenhouse for 2 years (2007-2008). The optimal concentration of a sex pheromone was 1.0㎎ per hexane 100㎕ in a using pheromone lure. There was no significant effect of the attraction of male adults among different colours (white, blue and yellow) of plate-type trap baited with sex pheromone. The more male adults were attracted, as the distance of a pheromone trap form a citrus tree infested with cryptic mealybug was closer. The male adults were caught to sex pheromone trap from middle April to late November, and its peak period was the middle of July. The thermal constant for the next attraction was about 640 degree-days (lower threshold temperature=12℃) after confirmed the first attraction of male adults. The optimum control time for cryptic mealybug after the first attraction of male adults were confirmed was estimated as 450 to 500 degree-days.

The study was conducted to explore whether environmental differences, in this case the physical characteristics of abaxial leaf surfaces of strawberry cultivars ('Maehyang' and 'Sulhyang' cultivars), affect the functional response of adult female N. californicus preying on immature stages (egg, larva and nymph) of T. urticae. We also evaluated the functional response of N. californicus to eggs of T. urticae at different temperatures (15, 20, 25, 30 and 35℃). We conducted a logistic regression of the proportion of prey consumed as a function of initial prey density to identify functional response types, and used nonlinear squares regression and the random predator equation to estimate attack rates and handling times. The functional response of adult female N. californicus to T. urticae was not influenced by non-glandular trichomes and epicuticular waxes on the abaxial leaf but was affected by temperature. Overall, the functional response of adult female N. californicus exhibited a type 2 functional response to T.urticae. The handling time of N. californicus was highest (1.9970) against T. urticae nymphs. The attack rate did not change much at 15-30℃, but the handling time decreased linearly with increasing temperature. At 35℃, the attack rate was highest (0.1876) and the handling time was lowest (0.9296). The results of this study may be used to evaluate the potential of N. californicus to suppress T. urticae and to estimate parameters for relevant prey-predator models.

In the present study a two-mode, separately concurring resonant cavity model is proposed for theoretical interpretation of the 3 minute umbral oscillation. The proposed model has been investigated by calculating the transmission coefficients of the waves propagating through the umbral photosphere (photospheric weak-field cavity) and chromosphere (chromospheric strong-field cavity) into the corona, for 3 different umbral model atmospheres by Staude (1982), Beebe et al. (1982) and Avrett (1981). In computing the transmission coefficients we made use of multi-layer approximation by representing the umbra] atmosphere by a number of separate layers with (1) temperature varying linearly with depth and (2) temperature constant within each layer. The medium is assumed to be compressible, non-viscous, perfectly conducting under gravity. The computed resonant periods, transmission spectra, phase spectra, and kinetic energy density of the waves associated with the oscillations are presented in comparison with the observations and their model dependent characteristics are discussed.

본 연구에서는 VFSMOD-W 모형을 활용하여 새만금 유역의 초생대 기법 적용에 따른 유사저감효과를 예측하고자 하였다. 먼저 모형의 신뢰도 확보를 위해 새만금 유역 내 초생대 실측치를 활용하여 매개변수를 보정하였으며, 새만금 유역 내 밭경지 특성을 파악하여 이를 토대로 모의 시나리오를 개발하였다. 다양한 밭경지 특성을 반영하기 위해 개발된 모의시나리오는 밭경지 규모 1 ha, 5 ha, 10 ha로 밭의 폭과 길이 비는 1 : 1를 적용 하였으며, 밭의 경사는 7%, 15%를 고려하였다. 또한 강우조건은 50 mm, 100 mm, 150 mm, 200 mm 일강우량을 적용하였다. 그 결과, 초생대의 유출저감효과는 밭경사 7%와 15%에 대해 2.9~13.5%, 2.9~12.1%로 각각 나타났으며, 유사저감효과는 33.8~97.0%, 27.1~85.9%로 각각 나타나 유출저감효과에 비해 상대적으로 높은 저감효과를 나타내었다. 유출 및 유사 발생에 영향을 미치는 밭규모, 경사 및 강우량 인자에 따라 초생대 효과는 큰 차이를 나타내었다. 본 모의 결과를 바탕으로 새만금 유역내 밭경지 규모 10 ha 미만, 경사 15% 이내의 조건에서 밭면적 10% 규모로 초생대를 조성할 경우 유사저감 효과를 기대할 수 있을 것으로 사료된다.

Background : Licorice has been used as a source of medicine and a food material in East-Asia. Recently, demand for licorice increased in market due to a growing interest in health. Thus we conducted breeding research to solve the problems associated with domestically cultivated licorice such as low productivity and low glycyrrhizin content. Methods and Results : We crossed European licorice (G. glabra L.; female parent) and Chinese licorice (G. uralensis Fisch; male parent) in the greenhouse in May 2007. In September 2007, crossed and germinated seeds were retrieved and sown in the greenhouse. In June 2008, stolons were separated from the F1 licorice seedlings and cultivated, resulting in 32 clonal lines of interspecific hybrids. Among them we selected good lines and then conducted the replicated yield trials (RYT) in 2012-2013 and local adaptability test (LAT) in 2014-2015. The results, GLYES9 showed that was elect of stem, oblong of leaf shape, red-brown of root color. Glycyrrhizin conten of GLYES9 (3.0%) was higher than G. uralensis (1.9%) at four regions from 2014 to 2015. GLYES9 was less than 10% in the desease of brown spot (G. uralensis was more than 30%). The root yield of GLYES9 was 4.31 ton per hectare, which was increased 193% compared with a check variety of G. uralensis. Therfore, we named GLYES9 as new cultivar ‘Dagam’. Conclusion : Depending on the above results, we have developed a new licorice cultivar ‘Dagam’ by the medicinal crop breeding team of National Institute of Horticulture and Herbal Science, RDA, in 2015. It showed brown spot disease resistant, high-glycyrrhizn content and high-yielding than colleted Glycyrrhiza spp.

Background : Cucuma longa L., in the family Zingiberaceae, is distributed in tropical and/or sub-tropical regions mainly in India and China. This species is commonly called tumeric, powder is used as medicinal herbs and/or flavor enhancer. It has been cultivated in southern region mainly Jindo. However, it might be possible to extend cultivation region due to rise in average temperature. In order to select superior lines, agronomic characteristics is commonly used. Because this is not the ultimate solution, the DNA marker approach has benefited the modern plant breeding. Therefore an easy approach by using one kind of primer have been developed from random amplification of polymorphic DNA sequences (RAPD) to discriminate effectively between different cultivars of Cucuma species Methods and Results : DNAs were extracted from the harvested roots of Cucuma sp. using DNeasy plant Mini kit (Qiagen, Hilen, Germany). These plants cultivated from GARES (Hamyang) and used for PCR amplification. The relative concentration of the extracted DNA was estimated Nano Drop ND-1000 (NanoDrop Technologies, Wklmington, De, USA) and final DNA concentration was adjusted to 5.5 ng/㎕. In this study 9 primer pairs were tested on 8 Cucuma sp. These primers showed polymorphism in Cucuma sp. The cluster dendogram showed that the similarity coefficients ranged from 0.68 to 0.87, CUR02 turned out to be CUR11, and CUR16 is similar to CUR17. Conclusion : These finding could be used for further research on cultivar development by using molecular breeding techniques and for conservation of the genetic diversity of Cucuma species. These data on polymorphism difference based on RAPD will be give us invaluable breeding information by selection of superior lines.

Acanthopanax species is known commonly as Siberian ginseng, touch-me-not, devil’s shrub, prickly eleutherococc, eleutherococc and wild pepper. A diverse group of chemical compounds isolated from Acanthopanax species was named ‘eleutherosides’. Among eleutherosides, eleutherosides B and E were widely known in Acanthopanax species. Acanthopanax species are cultivated and grow wild in a various area of Korea and have a variety of pharmacological effects. But, there are a lot of difficulties on producing excellent Acanthopanax species, according to the cultivated method is different pharmacological ingredients. This study, therefore, analyzed eleutherosides B and E in A. divaricatus and A. koreanum by different fertilizer ratio using HPLC. We will be investigated a high content of eleutherosides B and E by different fertilizer ratio and suggest an efficient fertilizer ratio of A. divaticatus and A. koreanum. All samples of A. divaricatus and A. koreanum were collected at Yeongcheon Agricultural Technology & Extension Center, Yeongcheon, Korea. The sample was prepared by upper and lower parts. The fertilizer ratio are N-P-K(10.5-8.5-8.5: 50 kg/10a), 2N-P-K (21-8.5-8.5: 50 kg/10a), N-2P-K (10.5-17-8.5: 50 kg/10a), N-P-2K (10.5-8.5-17: 50 kg/10a), and 2N-2P-2K (21-17-17: 50 kg/10a), respectively. To analyze eleutherosides B and E, 5 g of A. divaricatus and A. koreanum was extracted with 50% MeOH (3 × 100 ml) by reflux and evaporated in vacuo. The residue was dissolved in 1 ml of MeOH. The resulting solution was used for HPLC analysis. HPLC separation of eleutherosides B and E for qualitative and quantitative analysis was performed using a reverse phase system. A Discovery®C18 (4.6 × 250 mm, 5 μm) column was used with a mobile phase that consisted of water and acetonitrile. A gradient solvent system of water and acetonitrile (90:10 to 70:30 for 20 min) was used for the elution program. UV detection was conducted at 350 nm. The injection volume was 10 μl and the flow rate was 1 ml/min. All injections were performed in triplicate. The different fertilizer ratio yielded total eleutherosides B and E contents of 4.417-6.905 and 3.652-7.227 mg/g in the upper and lower parts of A. divaricatus, respectively. In A. koreanum, the total eleutherosides B and E contents were 4.591-10.108 and 3.834-9.079 mg/g in the upper and lower parts, respectively. The best conditions to increase eleutherosides B and E content in A. divaricatus was determined to be with N-2P-K fertilizer ratio, on the other hand, in A. koreanum was 2N-2P-2K fertilizer ratio.