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The National Institute of Meteorological Sciences-Korea Meteorological Administration (NIMS-KMA) has participated in the Coupled Model Inter-comparison Project (CMIP) and provided long-term simulations using the coupled climate model. The NIMS-KMA produces new future projections using the ensemble mean of KMA Advanced Community Earth system model (K-ACE) and UK Earth System Model version1 (UKESM1) simulations to provide scientific information of future climate changes. In this study, we analyze four experiments those conducted following the new shared socioeconomic pathway (SSP) based scenarios to examine projected climate change in the twenty-first century. Present day (PD) simulations show high performance skill in both climate mean and variability, which provide a reliability of the climate models and reduces the uncertainty in response to future forcing. In future projections, global temperature increases from 1.92 °C to 5.20 °C relative to the PD level (1995–2014). Global mean precipitation increases from 5.1% to 10.1% and sea ice extent decreases from 19% to 62% in the Arctic and from 18% to 54% in the Antarctic. In addition, climate changes are accelerating toward the late twenty-first century. Our CMIP6 simulations are released to the public through the Earth System Grid Federation (ESGF) international data sharing portal and are used to support the establishment of the national adaptation plan for climate change in South Korea.

Drynaria bonii H. Christ is a medicinal plant that has traditionally been used for the treatment of chronic diseases and tuberculosis. However, D. bonii has not yet been cultivated or propagated. In this study, we optimized the conditions for the spore culture of D. bonii to produce sporophytes. First, we evaluated the effects of various factors, such as temperature, light intensity, potting material, and pH, on spore germination and early gametophyte development. Under optimal culture conditions, 95–99% of the spores germinated within 2 weeks of culture. Next, based on these results, we established a culture system for gametophyte development and sporophyte production. Mature gametophytes first appeared 5 months post-germination (mpg), and at 12 mpg, the rate of production of heart-shaped gametophytes reached 56.6%. Sporophytes at the early first-leaf stage first appeared at 6 mpg, and at 12 mpg, the rate of formation of sporophytes reached 15.4%. Interestingly, 6.3% of all gametophytes produced multiple sporophytes. Additionally, 42–62% of the gametophytes also produced multiple secondary gametophytes, indicating a high potential of D. bonii gametophytes to generate new gametophytes and, subsequently, sporophytes. When transferred to new trays or pots, sporophytes grew well and showed 100% survival. Overall, we conclude that this spore culture system can be successfully used for the propagation of D. bonii sporophytes.

We analyze annual extremes of daily maximum and minimum surface air temperature and of daily rainfall in East Asia and the Korean peninsula. This study made intensive use of the simulation data available from the CMIP5 (Coupled Model Intercomparison Project Phase 5) multimodels in historical and future experiments up to the year 2100, employing three different radiative forcings: RCP2.6, RCP4.5, and RCP8.5 (representative concentration pathways). Several reanalysis datasets are used to compare and evaluate the simulated climate extremes in the late twentieth century. We estimate the future changes in precipitation and temperature extremes in East Asia and Korea, and compare them to the global result, for the reference period 1986–2005. The rising rate of future cold extremes over East Asia and Korea is faster than that of warm extremes. This phenomenon appears more distinctly in Korea as a local scale, indicating more sensitivity of the Korean peninsula to global warming. The increase of the 20-year return level of maximum precipitation in the CMIP5 over East Asia by the end of twenty-first century is about 7% in the RCP2.6, 15% in the RCP4.5, and 35% in the RCP8.5 experiments, which exceed the corresponding global values. We also estimate the changes in precipitation extremes across East Asia as a function of the annual mean temperature variation at the same location. The CMIP5 sensitivity in maximum precipitation across East Asia is 5.5%/∘C, which is lower than the global figure (5.8%/∘C). The sensitivity for the Korean peninsula is 7.38%/∘C, indicating the strong impact of global warming to Korea. The results will be important in mitigating the detrimental effects of variations of climatic extremes and in improving the regional strategy for water resource and eco-environmental management, particularly for such areas in East Asia under significant changes in temperature and rainfall extremes.

It is important to evaluate leaching behavior in agricultural soils to prevent the pollution of groundwater by pesticides. We identified the distribution coefficients (Kd) of ten pesticides with different physicochemical properties and compared their leaching characteristics using wick lysimeters from three distinct soil types on Jeju Island. The Kdvalues varied by pesticide and soil, but were within the range of 1.2 to 4231 L kg−1. Based on the European standard (Kd −1), six pesticides (alachlor, ethoprophos, carbofuran, napropamide, tebuconazole, and etridiazole) were mobile in at least one tested soil, and their soil organic carbon affinity was ≤ 5.811. This value differed greatly from the other pesticides (16.533 and higher). The solubility of the six mobile pesticides was ≥ 32 mg L−1, which substantially differed from the other pesticides (≤ 0.71 mg L−1). Thus, we conclude that our mobility assessment, which is based on Kdvalues, can be used to predict the leaching of pesticides in the volcanic ash soils of Jeju Island. The use of pesticides should be strictly controlled to reduce the possibility of groundwater contamination.

This modeling study investigates the impacts of increasing atmospheric CO2 concentration on acidification in the East Sea. A historical simulation for the past three decades (1980 to 2010) was performed using the Hadley Centre Global Environmental Model (version 2), a coupled climate model with atmospheric, terrestrial and ocean cycles. As the atmospheric CO2 concentration increased, acidification progressed in the surface waters of the marginal sea. The acidification was similar in magnitude to observations and models of acidification in the global ocean. However, in the global ocean, the acidification appears to be due to increased in-situ oceanic CO2 uptake, whereas local processes had stronger effects in the East Sea. pH was lowered by surface warming and by the influx of water with higher dissolved inorganic carbon (DIC) from the northwestern Pacific. Due to the enhanced advection of DIC, the partial pressure of CO2 increased faster than in the overlying air; consequently, the in-situ oceanic uptake of CO2 decreased.

The Agrobacterium-mediated transient assay is a relatively rapid technique and a promising approach for assessing the expression of a gene of interest. Despite the successful application of this transient expression system in several plant species, it is not well understood in spinach. In this study, we analyzed various factors, including infiltration method, Agrobacterium strain and density, and co-infiltration of an RNA silencing suppressor (p19), that affect transient expression following agroinfiltration in spinach. To evaluate the effects of these factors on the transient expression system, we used the β-glucuronidase (GUS) reporter gene construct pB7WG2D as a positive control. The vacuum-based infiltration method was much more effective at GUS gene expression than was the syringe-based infiltration method. Among the three Agrobacterium strains examined (EHA105, LBA4404, and GV2260), infiltration with the GV2260 strain suspension at a final optical cell density (OD600) of 1.0 resulted in the highest gene expression. Furthermore, co-expression of suppressor p19 also increased the efficiency and duration of gene expression and protein accumulation. The results indicate that the use of optimized conditions for transient gene expression could be a simple, rapid, and effective tool for functional genomics in spinach.

Virus-induced gene silencing (VIGS) is known as a rapid and efficient system for studying functions of interesting genes in plants. Tobacco rattle virus (TRV) is widely applied for the gene silencing of many plants. Although spinach is a TRV-susceptible plant, a TRV-based VIGS system has not yet been developed for spinach. In this study, we established a TRV-based VIGS system for spinach. To evaluate the functionality of the TRV-based VIGS system, the phytoene desaturase gene (SoPDS) was first isolated from spinach as a marker gene. Then, the VIGS vector pTRV2 was combined with the partial fragment of SoPDS gene in sense or antisense orientation. Using the Agrobacterium infiltration method, we introduced the pTRV2-SoPDS clone to silence the SoPDS gene in spinach. SoPDS was efficiently silenced, and consequently, greater than 90% of newly emerging leaves exhibited severe chlorosis symptoms in the treated plants. Levels of chlorosis symptoms were similar in both plants infected with pTRV2 vectors harboring sense (SoPDS_S) or antisense (SoPDS_A) gene fragments. Quantitative analysis of SoPDS gene expression by qRT-PCR revealed that gene expression was reduced by greater than 90% in both SoPDS_S and SoPDS_A VIGS plants. Chlorosis on leaves was prolonged up to 4~5 wk after Agrobacterium infiltration. The TRV-based VIGS system was effective in silencing the SoPDS gene in spinach, suggesting that it can be a useful reverse genetics tool for the functional study of spinach genes.

Algal blooms are one of the greatest aquatic environmental concerns, and the control of algal blooms has become a great challenge in recent years. In this study, we evaluated the effects of Bidens pilosa plant extracts in comparison to those of several widespread plants, including rice (Oryza sativa), Pistia stratiotes, Eichhornia crassipes, and Pteris vittata, on the growth of the bloom-forming blue-green alga Microcystis aeruginosa. Both ethanolic and methanolic extracts of B. pilosa, in contrast to the other plant extracts, exhibited high inhibitory effects on M. aeruginosa growth at a concentration of 500 mg/L (dry weight equivalent, DWE). The inhibition efficiency in terms of the cell density and chlorophyll a concentration significantly reached 84–88% (p

In this study, five regional climate models (RCMs) participating in the CORDEX-East Asia project (HadGEM3-RA, RegCM4, SNU-MM5, SNU-WRF, and YSU-RSM) are evaluated in terms of their performances in simulating the climatology of summer extremes in East Asia. Seasonal maxima of daily mean temperature and precipitation are analyzed using the generalized extreme value method. RCMs show systematic bias patterns in both seasonal means and extremes. A cold bias is located along the coast, whereas a warm bias occurs in northern China. Overall, wet bias occurs in East Asia, but with a substantial dry bias centered in South Korea. This dry bias appears to be related to the colder ocean surface around South Korea, positioning the monsoonal front further south compared to observations. Taylor diagram analyses reveal that the models simulate temperature means more accurately compared to extremes because of the higher spatial correlation, whereas precipitation extremes are simulated better than their means because of the higher spatial variability. The latter implies that extreme rainfall events can be captured more accurately by RCMs compared to the driving GCM despite poorer simulation of mean rainfall. Inter-RCM analysis indicates a close relationship between the means and extremes in terms of model skills, but it does not show a clear relationship between temperature and precipitation. Sub-regional analysis largely supports the mean–extreme skill relationship. Analyses of frequency and intensity distributions of daily data for three selected sub-regions suggest that overall shifts of temperature distribution and biases in moderate–heavy precipitations contribute importantly to the seasonal mean biases.

We present climate responses of Representative Concentration Pathways (RCPs) using the coupled climate model HadGEM2-AO for the Coupled Model Intercomparison Project phase 5 (CMIP5). The RCPs are selected as standard scenarios for the IPCC Fifth Assessment Report and these scenarios include time paths for emissions and concentrations of greenhouse gas and aerosols and land-use/land cover. The global average warming and precipitation increases for the last 20 years of the 21st century relative to the period 1986-2005 are +1.1°C/+2.1% for RCP2.6, +2.4°C/+4.0% for RCP4.5, +2.5°C/+3.3% for RCP6.0 and +4.1°C/+4.6% for RCP8.5, respectively. The climate response on RCP 2.6 scenario meets the UN Copenhagen Accord to limit global warming within two degrees at the end of 21st century, the mitigation effect is about 3°C between RCP2.6 and RCP8.5. The projected precipitation changes over the 21st century are expected to increase in tropical regions and at high latitudes, and decrease in subtropical regions associated with projected poleward expansions of the Hadley cell. Total soil moisture change is projected to decrease in northern hemisphere high latitudes and increase in central Africa and Asia whereas near-surface soil moisture tends to decrease in most areas according to the warming and evaporation increase. The trend and magnitude of future climate extremes are also projected to increase in proportion to radiative forcing of RCPs. For RCP 8.5, at the end of the summer season the Arctic is projected to be free of sea ice.

We developed an efficient Agrobacterium-mediated transformation protocol for spinach (Spinacia oleracea L.) that uses root-derived callus. Evaluation of this protocol was based on the systematic evaluation of factors that influence transformation efficiency. Four of the five factors that were tested significantly affected the transformation efficiency, including spinach cultivar, Agrobacterium tumefaciens strain and density, and the duration of co-cultivation. Transgenic spinach plants were generated based on optimized conditions, consisting of callus explants of the cultivar Gyeowoonae, A. tumefaciens strain EHA105 with OD600 of 0.2, a co-cultivation period of 4 d, and 100 μM acetosyringone supplemented in the inoculation and co-cultivation media. After co-cultivation with A. tumefaciens, explants were cultured in low-selective and then non-selective conditions to enhance the growth of putative transgenic explants. Visualization of the fluorescent marker, enhanced green fluorescent protein (EGFP), was used to select transgenic explants at several stages, including callus, somatic cotyledonary embryo, and plantlet. The best results for fluorescence visualization screening were obtained at the somatic cotyledonary embryo stage. On average, 24.96 ± 6.05% of the initial calli regenerated shoots that exhibited EGFP fluorescence. The putative transgenic plants were subjected to β-glucuronidase (GUS)-staining assay, phosphinothricin acetyltransferase (PAT) strip test, and molecular analyses to assess the transgene incorporation into plant genome and its expression. All EGFP-positive plants tested were confirmed to be transgenic by GUS-staining assay, PAT strip test, and molecular analyses. The transformation system described in this study could be a practical and powerful technique for functional genetic analysis and genetic modification of spinach.

Blue chanterelle (Polyozellus multiplex), known as an edible mushroom, was extracted using methanol to screen on anti-viral agent. Syncytium formation in Newcastle disease virus (NDV)-infected baby hamster kidney (BHK) cell originates from the trafficking of viral glycoprotein into cell-surface. Blue chanterelle inhibited not only syncytium formation, but also trafficking of glycoprotein, hemagglutinin-neuramidase (HN), onto cell-surface. Viral glycoprotein is processed within the endoplasmic reticulum during routing to surface. Blue chanterelle extracts showed the inhibitory activities (IC50 10 μg/mL) against α-glucosidase. These results suggested that blue chanterelle extracts inhibited the cell-surface expression of NDV-HN glycoprotein without significantly affecting HN glycoprotein synthesis in NDV-infected BHK cells.

Miraculin gene containing the N-terminal signal peptide was introduced into navel orange (Citrus sinensis Osb. var. brasiliensis Tanaka) callus cells by Agrobacterum-mediated transformation. Transgenic somatic embryos were screened on the shoot induction medium containing 25 mg hygromycin L−1. Citrus callus cells were reproduced from the green color somatic embryos on the callus reproduction medium. The obtained transgenic cells were cultured in Murashige and Tucker’s liquid medium containing 50 g sucrose L−1 in a shaking incubator. Similar to the native miraculin, the secreted recombinant miraculin protein formed a disulfide-linked dimer and retained taste-modifying activity. The stability of recombinant protein expression was confirmed over nine generations of callus. This production system can be an excellent alternative for producing various recombinant proteins as well as miraculin.

To better understand 20-hydroxyecdysone (20E) fluctuation and accumulation in perennial plant, 20E concentration in individual organs of Achyranthes japonica during reproductive growth stage were analyzed by high performance liquid chromatography (HPLC). Concentrations of 20E in root and floral part were much higher than those in stem and leaf during reproductive growth stage and rapidly increased from flowering stage in August to seed-setting stage in October, and thereafter decreased at the stage of seed maturing in November. In contrast, the 20E concentrations in stem and leaf gradually decreased during reproductive growth. In the analysis of detailed fluctuation of 20E in floral part, the 20E concentration was highest in the seed at the early stage of seed development, compared to flower, peduncle, seed coat, and/or seed in other growth stages, and decreased during seed maturation. The accumulation of 20E in reproductive organs, especially seed and root, suggests that 20E has a defensive role for protection of especially newly developing organs against phytophagous insects.

A cDNA library was constructed from the newly developed young leaves of Aralia elata Seem, and a total of 2,755 cDNAs were partially sequenced. Sequences with high quality greater than 150 bp after trimming vector and ambiguous sequences resulted in 2,689 ESTs. These ESTs were clustered into 2,010 unigenes consisting of 376 contigs with two or more ESTs and 1,634 singletons. A homology search with BLASTX against the NCBI database identified 1,256 (63%) unigenes homologous to proteins of known or putative function, 350 (17%) genes assumed as proteins with unknown function, and 404 (20%) unigenes with no significant match to any protein sequence, including sequences with matches greater than the E value of −105 in the NCBI database. The expression level of each gene was analyzed based on the number of cDNA clones in each contig composed of at least 10 ESTs. The most abundant gene identified was acid phosphatase. The genes related to chlorophyll a-b binding protein, elongation factor 1-alpha, ribulose 1,5-bisphosphate carboxylase small subunit and cyclophilin were also plentiful. The 1,259 unigenes matched with proteins of known or putative function were classified into a functional category using the MIPS BLAST program and 616 unigenes were assigned to putative biochemical functions. Furthermore, five, sixteen and twelve unigenes in our EST set were assumed as proteins involved in squalene synthesis, cytochrome P450 and glycosyltransferase, respectively. These genes should be further explored for their involvement in the saponin biosynthesis pathway in A. elata Seem.

The objective of this study was to develop an efficient system for the regeneration of spinach plants (Spinacia oleracea L.) by investigating the factors influencing callus and shoot induction. All plant growth regulator (PGR) combinations tested induced callus with high frequency (73–100 %), and the combination of 5 μM α-naphthaleneacetic acid (NAA), 10 μM 6-benzyladenine (BA) and 0.1 μM gibberellic acid (GA3) had the most significant effect on callus growth in term of weight (120.98 ± 22.56 mg). A high auxin-containing medium induced competent callus for shoot formation, while high cytokinin-containing media enhanced callus growth and made callus incompetent for shoot regeneration. Longer periods of callus induction in a high auxin-containing medium were required to form competent callus and led to a high regeneration capacity. The PGR combination shift from a high auxin to cytokinin ratio (ACR) to a low ACR resulted in highly efficient regeneration. Among the regeneration systems tested, the combination of 10 μM NAA and 0.3 μM GA3 for callus induction for 6 weeks followed by 2 μM NAA and 5 μM BA resulted in the highest plant regeneration frequency (83.33 ± 6.43 %) and the highest number of plantlets per explant (7.93 ± 1.24). Somatic embryos at cotyledonary stage and plantlets were transferred to PGR-free medium to establish whole plants. Regenerated female plants grew well to maturity in the greenhouse (77.17 ± 9.80 %) and produced seeds (175.21 ± 28.01 firm seeds per plant).

Satsuma mandarin (Citrus unshiu Marc.) is characterized by its tender peel and seedless nature. The representative cultivar of Satsuma mandarin is Miyagawa wase. Another cultivar, Ueno wase was developed from the bud mutation of a Miyagawa wase tree. Compared to Miyagawa wase fruit, Ueno wase fruit is known to have less albedo, higher sugar content, and to mature earlier. To find genes related to this bud mutation, a citrus 300 k DNA microarray was developed for gene expression analyses of the fruits and leaves of each cultivar. When up-regulated genes were classified in the Cluster of Orthologous Groups of proteins database, the number of genes included differed significantly between the two cultivars. Ten genes, including cytochrome P450, α-mannosidase, S-adenosylmethionine decarboxylase, carboxyesterase, anthranilate synthase, glycosyl hydrolase family-17, ethylene response factor subfamily, and alcohol dehydrogenase, showing significant differences in gene expression by DNA microarray were selected, and their expression patterns were examined by RT-PCR. The information gained from genes that are up (or down)-regulated upon bud mutation may explain the observed phenotypes, while also increasing the understanding of genes related to citrus bud mutation.

To profile gene expression in the early stage of fruit development from ‘Nichinan No. 1’ satsuma mandarin (Citrus unshiu Marc.), we isolated total mRNA at 30 d after flowering. A cDNA library was prepared from mature mRNAs and a total of 2350 cDNA clones were partially sequenced. In all, 1914 ESTs were acquired after the removal of the vector sequence and filtering over a minimum length of 150 nucleotides. A total of 763 unigenes, consisting of 138 contigs and 625 singletons, was identified after assembly of those ESTs. According to our homology search with BLASTX against the NCBI database, the deduced amino acid sequences of 253 unigenes were homologous to proteins with known function and 242 unigenes were significantly matched to proteins with putative or unknown functions. The remaining 268 showed no significant similarity to any protein sequences found in the public database with matches higher than an E value of 10-5. The 253 unigenes matched to proteins with known function were then manually assigned to 10 cellular functional categories using a modified MIPS MATDB classification. The expression level of each gene was analyzed based on the redundancy of cDNA clones in each contig that comprised more than 10 ESTs. Here, the most abundant gene expressed in young fruits was for a chitinase precursor. A miraculin-like protein and a lectin-related protein precursor were also abundant.

The enantiomerically pure diastereoisomers (1R,4S,4aR,7S,7aR)- (1) and (1R,4R,4aR,7S,7aR)-dihydronepetalactol (2) were synthesized diastereoselectively from a renewable resource, (4aS,7S,7aR)-nepetalactone (3), isolated as the main constituent of the essential oil of the catmint plant Nepeta cataria. The stereochemistry of the compounds was determined by NMR spectroscopy and X-ray crystallography, and the compounds were identified, respectively, as neomatatabiol and isoneomatatabiol, natural products from Actinidia polygama, for which the lactol stereochemistry was previously incompletely defined. Compound 1 was found to catch significant numbers of three species of lacewing in the field: in Korea, Chrysopa cognata, and in the United Kingdom, Nineta vittata and most notably Peyerimhoffina gracilis. All species caught in significant numbers were found more frequently in traps releasing 1 than 2, while more C. cognata, C. formosa, and C. phyllochroma were found in traps releasing (1R,4aS,7S,7aR)-nepetalactol (4). The catch of P. gracilis with 1 is of particular interest as this lacewing has only recently been recorded in the United Kingdom. Where sexed, the lacewings of all species trapped were found to be male, implying a possible pheromonal role for these or structurally related compounds.

Chemical analysis of the volatiles released by sexual females (oviparae) of the peach aphid, Tuberocephalus momonis, identified two ubiquitous aphid sex pheromone components, (4aS,7S,7aR)-nepetalactone and (4aS,7S,7aR)-nepetalactol, in a ratio of 4 : 1. In field trials in Korea, employing traps releasing the two compounds in differing ratios, the most effective sex pheromone blend for trapping male T. momonis was found to be 85 : 15 nepetalactone–nepetalactol. Surprisingly, large numbers of presexual females (gynoparae) of this species were also collected when the catching rates were highest. In addition to T. momonis, over 20 other species of aphids were caught, particularly Myzus lythri, M. dycei, Lachnus tropicalis and M. persicae, in descending order of abundance.

Chemically mediated interactions between an egg parasitoid, Trichogramma chilonis, and its host insect, Helicoverpa assulta, were studied in laboratory experiments. T. chilonis was attracted to the sex pheromone of H. assulta, and, among four components of its sex pheromone, (Z)-11-hexadecenyl acetate seemed to be most attractive. T. chilonis was also highly attracted to (E)-12-tetradecenyl acetate, a component of the sex pheromone of Ostrinia furnacalis, another host. H. assulta eggs were more parasitized by T. chilonis when the eggs were treated with male moth scale extract (MSE) of H. assulta. Parasitism was also affected by the age of the parasitoid, time of day, and MSE concentration. Silica gel chromatography and subsequent argentation chromatography for MSE fractionation indicated the activity was associated with the fraction of saturated hydrocarbons. A linear olfactometer experiment revealed that H. assulta eggs also contain a short-range attractant(s).

Electroantennograms (EAGs) were recorded from two predatory insect species, the twelve-spotted lady beetle, Coleomegilla maculata and the green lacewing, Chrysoperla carnea in response to semiochemicals emitted from one of their prey species, the pea aphid Acyrthosiphon pisum and their host plant. EAG responses were also recorded from C. maculata in response to extracts from individuals of the opposite sex and to extracts from an herbaceous plant, catnip Nepeta cataria. Extracts of catnip and two sex pheromone components of aphids, (4aS,7S,7aR)-nepetalactone and (1R,4aS,7S,7aR)-nepetalactol, elicited significant EAG responses from the antennae of both predatory species. Of 10 corn volatile compounds tested, C. carnea adults responded most strongly to 2-phenylethanol and (E)-β-farnesene. A significant difference in EAG response to extracts of corn leaf collections was observed between male and female C. carnea. In C. maculata, significant EAG responses were elicited by most of the tested corn volatile compounds, except α-pinene and (E)-2-hexenal. The highest EAG responses were observed in response to (E)-β-farnesene, α-terpineol, 2-phenylethanol, and β-caryophyllene. Sexual differences in EAG responses of C. maculata were only found in response to 1-octen-3-ol. Male antennae of C. maculata produced significant EAG responses to extracts from conspecific females, but not to males, which indicates that some chemicals from females could be involved in sexual communication. A significant EAG response also was recorded in response to the extracts of fluids produced during “reflex bleeding.” Male and female antennae of both species exhibited similar dose–response curves to most of the selected compounds, although female C. maculata antennae exhibited higher thresholds in response to several compounds including α-terpineol, (Z)-3-hexenol, and (4aS,7S,7aR)-nepetalactone. Field tests showed that 2-phenylethanol was highly attractive to both sexes of the two investigated species. Only C. maculata was attracted to traps baited with α-terpineol.

The lacewing Chrysopa cognata, one of the principal predators of aphids in Korea, was tested for responses to the aphid sex pheromone components (4aS,7S,7aR)-nepetalactone and (1R,4aS,7S,7aR)-nepetalactol and the aphid alarm pheromone (E)-β-farnesene. Electroantennogram responses were obtained to the sex pheromone components but not to (E)-β-farnesene. The sex pheromone components were attractive in a Y-tube olfactometer assay and in field trials with water traps, but no attraction was observed to (E)-β-farnesene.

The apple leafminer moth, Phyllonorycter ringoniella, is becoming a more serious insect pest on apple trees with four to five generations a year in Korea. In order to devise a forecasting method for more accurate estimation of their numbers and development timing, the sex attractant was studied. Various ratios, from 10:0 to 0:10, of the two components, (Z)-10-tetradecenyl acetate (Z10–14:Ac) and (E,Z)-4,10-tetradecadienyl acetate (E4,Z10–14:Ac), identified from the sex pheromone gland (Jung and Boo, 1997), were tested for attractivity in terms of behavioral response (taxis, approach, and landing) against P. ringoniella males in a wind tunnel. The lure with Z10–14:Ac/E4,Z10–14:Ac in a ratio of 4:6 elicited the highest response in two (taxis and approach) measurement categories. For eliciting landing behavior, the two blends of 5:5 and 4:6 were best. The single component, Z10–14:Ac, elicited taxis behavior, but a combination of two chemicals was needed for eliciting all three behaviors. In the field, male attraction to various lure mixtures in Pherocon IC traps was usually greater than attraction to virgin females. The best field activity was in the lure baited with a 4:6 ratio of Z10–14:Ac and E4,Z10–14:Ac. Similar results were obtained from tests conducted in a net house. This optimum ratio for attracting P. ringoniella males in Korea is different from those reported in Japan (10:3) or China (7:3 to 6:4). The isomer E10–14:Ac neither improved nor depressed the number of catches when added at up to 10% of the total mixture to lures of the two components in the 4:6 ratio. The attractivity of the lures increased with higher amounts of the pheromones, up to 10 μg in the wind-tunnel experiment and 5 mg in the apple orchard. The number of males captured was not significantly different among traps installed at 0.3, 1.5, or 2 m above the ground, or among wing, delta, or water traps. A rubber septum dispenser impregnated with 1 mg of the 4:6 mixture maintained its field attractivity for up to eight weeks.

The solvent fractions of rosemary methanol extract were obtained by successive extraction with n-hexane, chloroform, ethyl acetate, butanol, and water. The ethyl acetate fraction (EAF) contained a remarkable amount of polyphenol and flavonoid as well as high levels of alkyl and 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging activity. The activity guided fractionation and repeated chromatographic separations over silica gel, RP C18, and Sephadex LH-20 led to isolation of six compounds from the EAF. 1H NMR, 13C NMR, 2D NMR, MS, and IR spectroscopies determined the compounds to be caffeic acid (1), rosmarinic acid (2), rosmarinic acid methyl ester (3), luteolin (4), apigenin (5), and hispidulin (6), and high-performance liquid chromatography quantification was used to determine concentrations in EAF. Among the six isolated compounds, rosmarinic acid methyl ester showed the highest scavenging activities against di(phenyl)-(2,4,6-trinitrophenyl) iminoazanium, alkyl and ABTS radicals. The EAF mixture, but not individual isolated compounds, shielded dermal fibroblast cells from H2O2-induced cytotoxicity at concentrations that encompass the SC50 of alkyl and ABTS radical. Therefore, our findings suggested for the first time that antioxidant capacity of the EAF mixture result in a synergistic effect on the antioxidant action.

Effects of methanol extract of Terminalia chebula on antibacterial activity and the generation of superoxide radical in Bacillus subtilis, as well as on syncytium formation and cytopathic activity in virus-infected baby hamster kidney cells were examined. The extract effectively inhibited syncytium formation in a concentration-dependent manner, and infectious virus production was markedly reduced. However, glycoprotein synthesis was not affected. These results collectively indicate that methanol extract of T. chebula potentially inhibit glycosylation by acting as a suppressor of intracellular glycosylation trafficking.

Bruceanol B, isolated from a soil microbe strain DS4, generated oxygen radicals in Bacillus subtilis lysates. Bruceanol B inhibited the trafficking of viral glycoprotein in virus-infected baby hamster kidney (BHK) cells. Bruceanol B also effectively inhibited syncytium formation in a dosedependent manner. However, glycoprotein synthesis was not affected by the compound. Results indicate that bruceanol B generating oxygen radical has inhibitory activity in the trafficking of viral glycoprotein of BHK cell.

Strain DS4, a soil microorganism producing an oxygen radical-generating antibacterial substance, bruceanol B, was isolated, and cultural conditions for the antibiotic production were optimized. Bruceanol B was separated by ethyl acetate extraction, silica gel and Sephadex LH-20 gel column chromatographies, and high-performance liquid chromatography (HPLC). The highest antibacterial activity was obtained from medium containing 1.5% soluble starch and 2.0% yeast extract, cultured at 30°C for 3.5 days.

Miraculin is a taste modifying plant protein, which displays a peculiar property of being able to modify sour taste into sweet taste. Thus, there has been an increasing interest in miraculin due to this amazing property. In the present study, miraculin gene was introduced into the Miyagawa Wase Satsuma mandarin (Citrus unshiu Marc.) callus by Agrobacterum-mediated transformation to produce a citrus transgenic plant and express the recombinant miraculin protein under the control of 35S promoter. Satsuma mandarin is one of the choicest citrus varieties grown widely and commercially in Korea, especially in Jeju Island, and Japan. Expression of this protein in the transgenic plant resulted in the accumulation of a significant amount of the miraculin protein in the leaves. To investigate whether the expressed protein was correctly modified, the dimerization and N-glycosylation of recombinant miraculin in the transgenic plants were analyzed. The recombinant protein also showed a sufficient biological activity. These results open up a new way of expression system in woody plants such as citrus and can provide a suitable alternative for producing recombinant miraculin.

Methanol extracts of Paeonia lactiflora roots (Radix Paeaniae Lactiflora) had antibacterial activity against Bacillus subtilis. These extracts generated superoxide radicals in the B. subtilis lysate. However, the radicals were strongly detoxified by the addition of superoxide dismutase, an indication that superoxide radicals are important in the antibacterial actions of the extracts. The root extracts also showed a pivotal inhibition role in trafficking of viral glycoprotein in virusinfected baby hamster kidney (BHK) cells. The methanol extract effectively inhibited syncytium formation in a concentration-dependent, and it did not affect glycoprotein synthesis. These results suggest that oxygen radical affect the transport process of viral glycoprotein without its synthesis.

Analysis of ovipositor washings from virgin femaleHelicoverpa assulta (Guenée) (Lepidoptere: Noctuidae) from Korea by gas chromatography (GC) linked to electroantennography and GC linked to mass spectrometry resulted in the identification of nine compounds, hexadecanal, (Z)-9-hexadecenal, (Z)-11-hexadecenal, hexadecyl acetate, (Z)-9-hexadecenyl acetate, (Z)-11-hexadecenyl acetate, hexadecan-l-ol, (Z)-9-hexadecen-l-ol, and (Z)-11-hexadecen-1-ol. However, ovipositor washings from females from Thailand contained mainly the 16-carbon aldehydes with very small amounts of (Z)-9-hexadecenyl acetate. Field tests conducted in Korea, China, and Thailand indicated that a binary blend of (Z)-9-hexadecenal and (Z)-11-hexadecenal was sufficient for attraction, although the most attractive ratio of compounds varied with location. In Korea a 20∶1 blend of compounds was the most attractive, while in Thailand a 7.5∶1 blend was most attractive. In China both blends of hexadecenal isomers were equally attractive. Addition of the hexadecenyl acetates to the 20∶1 blend of hexadecenals in the ratio of 1∶3.3 increased the trap catch of maleH. assulta compared to lures containing the aldehydes alone in Korea but reduced trap catch in China. Addition of the hexadecenyl acetates to the 7.5∶1 blend of hexadecenals had no significant effect on trap catch in Thailand or China compared to the aldehydes alone. The addition of the 16-carbon alcohols to the aldehydes had a significantly inhibitory effect in all three countries, suggesting they are not pheromone components. Taken together these results indicate thatH. assulta is polymorphic with at least two populations responding to different sex pheromones.

The behavioural significance of (Z)-9-tetradecenal to male H. assulta was tested by comparing the number of moths attracted to lures containing a standard synthetic female sex pheromone with lures in which (Z)-9-tetradecenal was also added. The standard pheromone mixture used contained 1000 μg (Z)-9-hexadecenal, 50 μg (Z)-11-hexadecenal, 300 μg (Z)-9-hexadecenyl acetate and 15 μg (Z)-11-hexadecenyl acetate impregnated on rubber septa. Addition of (Z)-9-tetradecenal to the standard pheromone was shown to significantly reduce the caught of male H. assulta when added in amounts greater than 10 μg or 1% of the major pheromone component in both field and net-house experiments. The reduction in catch was found to be dependent on the quantity of (Z)-9-tetradecenal added to the standard pheromone. The implications of these results on conspecific and inter-specific pheromone-mediated communication in H. assulta and related sympatric heliothine species is discussed.