The antioxidant, xanthine oxidase, tyrosinase inhibitory activities and polyphenol contents of the fruiting bodies of Pleurotus cornucopae extracted with acetone, hot water and methanol (hereinafter referred to Fr. Ace, Fr. HW and Fr. MeOH). The antioxidant activities in the Fr. Ace, Fr. HW and Fr. MeOH were 93.23%, 89.55% and 92.58%, respectively at the concentration of 2.0 mg/ml. Xanthine oxidase inhibition activity in the Fr. Ace, Fr. HW and Fr. MeOH were 45.84%, 46.50% and 45.60%, respectively at the concentration of 5 mg/ml. Tyrosinase inhibition activity in the Fr. Ace, Fr. HW and Fr. MeOH were 52.11%, 50.12% and 55.81%, respectively at the concentration of 1.0 mg/ml. Total polyphenol contents in the Fr. Ace, Fr. HW and Fr. MeOH were 18.99 mgGAEs/ g, 16.73 mgGAEs/g and 18.66 mgGAEs/g. These experimental results suggested that fruiting bodies of P. cornucopae contained good physio-chemical substances for promoting human health.

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.

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.

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 : Gentinae Macrophyllae Radix is one of the traditional medicines originated from the roots of multiple plants, Gentiana macrophylla Pall., Gentiana straminea Maxim., Gentiana crassicaulis Duthie ex Burkill and Gentiana dahurica Fisch., in Gentianaceae. Multi-origin traditional medicine usually has adulteration problem based on the morphological similarity and/or misunderstanding the species. Therefore, accurate and reliable identification criteria to ensure drug safety and quality is necessary. Methods and Results : We collected four original species of Gentinae Macrophyllae Radix from plantations and markets in China and Korea. DNA barcoding with four barcoding markers (Internal Transcribed Spacer (ITS), rbcL, trnL intron, trnL-F intergenic sapcer) was performed. Intra-specific variation was observed in ITS nucleotide sequence however, successfully distinct four original species based on the nucleotide discrepancy while trnL intron has no difference. trnL-F intergenic spacer has two transitions(T→C and A→G) sites only in G. crassicaulis and rbcL shows one transition(C→T) site in G. dahurica and G. macrophylla. Phylogenetic relationship analysis of the Gentinae Macrophyllae Radix revealed two major clades – clade I including three groups, G. macrophylla, G. straminea and G. dahurica, and clade II including G. crassicaulis. This aspects was shown more clear with multi-region combined analysis. Conclusion : DNA barcoding will be accurate and powerful criteria for the analysis the origin of Gentinae Macrophyllae Radix. However, single region analysis might be deficient such as trnL intron, rbcL and trnL-F intergenic spacer results in this research. Multi-region combined analysis based on the multiregional DNA barcode markers will be overcome the disadvantage and also increase the precision.

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.

The rice straw managements are essential for maintaining soil fertility as well as reducing chemical fertilizer application in paddy field. A field experiment was conducted on moderately well draining alluvial paddy soil to investigate the decomposition pattern of rice straw. The mesh bags containing the rice straw harvested in the previous year were placed at soil surface and buried into around 10cm depth and recovered periodically for determining the straw decomposition. Pot experiments were conducted to investigate the fates of N released from 15 N-labeled rice straw under different levels of N fertilizer application. The overall decomposition patterns of rice straw were similar for the two incorporation depths in transplanted paddy field. The straw incorporated at transplanting date showed weight loss of about 50%, 70% and 90% after 2 months, 5 months, and 2 years, respectively. The decompositions of straw cell wall components showed somewhat different pattern. The decompositions of cellulose and silica were similar to that of dry weight while the decomposition of lignin was slower than that of cellulose and silica. N was released from rice straw 42% and 65 % of the initial N after one month and after five months, respectively. P release was faster than N release. Recoveries of rice straw-15 N by rice plants were 10.2, 13.4 and 14.9% in 0, 120 and 240 mg N pot-1 , respectively. Soil recoveries of rice straw 15 N were 17.3, 20.6 and 18.9% in 0, 120 and 240mg N pot-1 , respectively.

Two rice cultivars of the japonica type, ozone-resistant Ilpumbyeo (IL) and ozone-susceptible Keu-mobyeo#l (KM) were exposed to ozone (O3 ) at 0.15 ppm for 30 days. The available nutrient regimes were varied by doubling the supply of nitrogen (N), phosphorus (P) and potassium (K) within a basic fertilizer status (N, P, K; 15, 12, 12 kg l0a-1 ). There was little difference on plant height between ozone-treated and nontreated plants. The most significant ozone stress on tiller number was shown on the 30th day of ozone exposure. Slight recovery from ozone stress was noted on the 60th day. On the 30th day, tiller number was greatly decreased by 40.8% in IL and 64.6% in KM, whereas at a high nitrogen supply regime (2N), it was decreased by 21.4% in IL and 42.7% in KM as compared to the control not treated with ozone at basic fertilizer status. The inhibition of tiller production caused by ozone exposure was alleviated on the 60th day. In both cultivars, number of spikelets per plant and weight of 100 grains were affected little by the ozone treatment irrespective of nutrient regime. However, the number of panicles per plant and yield were reduced significantly. In both cultivars, yield of ozone-treated plants with 2N status was 12.4-16.1 % higher than that of the ozone-treated plants with basic nutrient status. A significant yield decrease of 47.8% and 33.4% was observed for IL and KM, respectively, in ozone-treated plants with higher potassium (2K) status.

Ozone (O3 )-induced changes in chlorophyll content and specific activities of antioxidant enzymes, such as superoxide dismutase (SOD), ascorbate peroxidase (APX), guaiacol peroxidase (GPX), dehydroascorbate reductase (DHAR) and glutathione reductase (GR) were investigated in two rice cultivars (Oryza sativa L.) grown under variable nutrient treatments. For this study, two rice cultivars of Ilpumbyeo (IL) and Keumobyeo#l (KM), which were known as resistant and susceptible to O3 , respectively, were exposed to O3 at 0.15ppm for 30 days and investigated with 10 days interval. The available nutrient regimes were varied by doubling the supply of nitrogen (N), phosphorus (P) and potassium (K) Within a basic fertilizer status (N, P, K; 15, 12, 12kg/l0a-1 ). In both cultivars and at all nutrient status, chlorophyll content in O3 -treated plants decreased with prolonged treatment period, although higher N, P and K supply with O3 treatment alleviated the decrease in chlorophyll content. The activities of almost all enzymes investigated for this study were decreased during initial stages of O3 - exposure except GPX which maintained higher activity throughout the exposure period than the non-treated plant. However, the antioxidant enzymes in O3 -treated plants showed almost the same or higher activities on 30 days after O3 - exposure. The most significant changes in activities were observed in GR of the O3 -treated leaves. With the prolonged treatment period, the activity of GR at 30 days was increased by 3-8 times compared to those in 10 days. Most of the investigated enzymes showed very similar tendency to O3 treatment in all fertilizer status. There was no observed evidence for enhanced detoxification of O3 -derived activated oxygen species in plants grown under higher fertilizer status compared with that in plants grown under basic fertilizer status. The increase in the activities of SOD, APX and GR in rice leaves by relatively long-term treatment with O3 at low concentration is considered to indicate that the plant became adapted to the O3 stress and the protection system increased its capacity to scavenge toxic oxygen species. Our results in two rice cultivars indicated that there was little difference in the activities of antioxidant enzymes between IL and KM, which were known as resistant and susceptible cultivar to O3