Dong Woon Lee

Nematocidal Screening of Essential Oils and Herbal Extracts against Bursaphelenchus xylophilus

Five essential oils and 15 herbal extracts were evaluated to control Bursaphelenchus xylophillus in laboratory. The essential oils from clove plant (Syzygium aromaticum), mustard (Brassica integrefolia), thyme (Thymus vulgaris), and Pelargonium inquinans were found to be highly promising and gave excellent control of the nematodes at all the time of exposure. Among them, the least one gave 91.3% mean mortality rate at 24 hours of exposure time, which is highly significant from the control. While in the second study, most of the methanol (Desmodium caudatum, Paulownia coreana, Auckulandia lappa, Sophota flavescens, Aloe sp., Rheum palmatum, Zingiber officinale, Magnolia officinalis, and Eugenia caryophyllata), hexane (Torreya nucifera, Pharbitis nil, Prunus mume, Melia azedarach, and Xanthium strumarium), and hot water (Cinnamomum cassia) herbal extracts killed the nematodes, but in varying degrees compared to the control. Only one extract was found to be promising viz Magnolia officinalis which found to be statistically different from the control and gave mean mortality of 72, 82.3, and 85.3 % for 24, 48, and 72 hours exposure, respectively. Further screening was conducted for M. officinalis with concentrations of 1,000, 100, and 10 ppm against the same species of nematode with the same time of exposure. However, it gave an excellent result for 1,000 ppm for all time of exposure, whereas for the 100 and 10 ppm it gave mean mortality of 39.5 and 25.8% for the time 72hrs, respectively that were statistically different from the control.

Life History and Spatial Distribution of Oriental Beetle (Coleoptera: Scarabaeidae) in Golf Courses in Korea

Abstract Larval and adult activity of the oriental beetle Exomala orientalis (Waterhouse), a pest of turfgrass in Korea, was investigated at four golf clubs in Pusan, Korea, from 1995 to 1999. Adult emergence was first observed on the greens in late May with peak activity occurring 2 wk later. During the day, E. orientalis adults were most active between 1800 and 2200 hours. First instars were found mostly in early July, second instars mostly in late July, and third instars from August to April. The density of larvae in fixed plots decreased steadily from the time of egg laying to pupation: 667/m3 on 26 July, 267/m3 on 29 August, and 122/m3 on 2 October 1997. All the observed E. orientalis completed one generation per year. Adult females were observed feeding on flowers of a late-blooming variety of Japanese chestnut (Castanea crenata Sieb & Zucc). E. orientalis larval densities were higher in greens with Japanese chestnut nearby, and where magpie, Pica pica sericea (Gould), feeding was observed. More E. orientalis adults emerged from the right, left, and back of greens than from the front or middle. The intensity of emergence was inversely proportional to the amount of golfer traffic on various parts of the green. Counting emergence holes may be a way that golf course superintendents can predict which greens and tees are most likely to be damaged from E. orientalis larvae without destructive sampling.

EFFECTS OF PURIFIED PERSIMMON TANNIN AND TANNIC ACID ON SURVIVAL AND REPRODUCTION OF BEAN BUG, Riptortus clavatus

We evaluated the effects of tannic acid and purified persimmon tannin on survival and reproduction of bean bugs, Riptortus clavatus. Feeding behavior of R. clavatus was also examined on sweet (cv. Fuyu) and astringent (cv. Chongdosi) persimmon fruits. Soluble tannin in sweet persimmon fruits decreased from 3% in early June to 0.5% in late September, but it increased from 2 to 8% during the same period in astringent persimmon fruits. More bugs visited sweet than astringent persimmon. Numbers of piercing/sucking spots were higher on sweet than on astringent persimmon. When fed 1 and 3% solutions of persimmon tannin, adult bugs ingested only 64.1 and 9.5% of the amount of water ingested by those offered the control (distilled water). Amounts of persimmon tannin ingested by the adult bugs were 6.5 and 2.8 times higher at 1 and 3% tannin solutions compared to a 0.1% solution. Persimmon tannin exerted negative effects on survival and reproduction of R. clavatus at higher concentrations (1 and 3% solutions). Feeding of R. clavatus adults decreased with increasing tannin concentrations. When results from both sexes were pooled, 50% mortality was achieved at 11 and 4 days after treatment with the 1 and 3% tannin solutions, respectively. Reproduction decreased with 1% tannin, and no eggs were produced with 3% tannin solution. Tannic acid was similar in its effects on R. clavatus. All nymphs died 14, 12, and 7 days after feeding on 0.1, 1, and 3% tannic acid, respectively. Adults were less sensitive than nymphs, and their survival was not affected by 0.1% tannic acid. However, 1 and 3% tannic acid solutions were fatal. Survivorship decreased to 50% at 11 and 6 days after supplying tannin solutions of 1 and 3% concentrations. Higher concentrations (1 and 3%) resulted in reduced reproduction, as was seen with persimmon tannin. Our data may explain why R. clavatus does not invade sweet persimmon orchards until late July, when concentrations of soluble tannin are low enough to allow them to feed.

Field evaluation on the synergistic attractiveness of 2-(1-undecyloxy)-1-ethanol and ipsenol to Monochamus saltuarius

To develop an optimal attractant for Monochamus saltuarius (Gebler) (Coleoptera: Cerambycidae), the synergistic effects of a few potential attractants (ethanol and α‐pinene as host‐plant volatiles, and ipsenol and ipsdienol as bark beetle pheromones) were tested in a pine forest combined with 2‐(1‐undecyloxy)‐1‐ethanol (monochamol), the aggregation pheromone of Monochamus species, for two consecutive years, 2014 and 2015. Total number of catches was 65 and 33 in 2014 and 2015, respectively. Ethanol or ethanol + monochamol (a base blend) were not attractive to M. saltuarius with no difference from the control. Addition of α‐pinene and ipsdienol to the base blend did not significantly increase catches. However, ipsenol was significantly synergistic to the base blend in attracting M. saltuarius in 2014, and the blend (ipsenol + base blend) attracted meaningfully higher numbers of M. saltuarius in 2015. Our study illustrates the potential for monochamol and ipsenol baits for monitoring and trapping of M. saltuarius in the field.

Damage of Zoysiagrass by Zoysiagrass Mite, Aceria zoysiae in Korean Golf Courses

This study provides basic information on morphological characteristics of zoysia mite, Aceria zoysiae and symptom in zoysiagrass for turfgrass management in golf courses. Zoysiagrass mite distributed from Pocheon, Gyeonggii province to Jinju, Gyeongnam province and damaged turfgrasses from spring to fall. Damaged leaf by zoysiagrass mite was rolled unidirectionally and mite damaged leaves in the inside of rolled part. Leaves was turned to yellow and damaged area formed irregular yellow patch.

Insect Pests in Turf Sod Production Areas in Korea

Turfgrass insect pests were investigated in different turf sod production areas of Korea. Twelve insect pest species of 7 families in 6 orders and one Eriophyidae mite, Aceria zoysiae were collected from turf sod production areas. The zoysiagrass mite was most frequently occurred zoysiagrass sod production areas. Damaged rate by zoysiagrass mite was increased from May to September. Noctuidae (Spodoptera depravata, Agrotis ipsilon and A. segetum) and Pyralidae (Crambus sp.) insect pests in Lepidoptera were attracted in A. ipsilon sex pheromone trap. Eggs and larva of A. ipsilon was the highest occurred August. Zoysiagrass mite and A. ipsilon were main insect pests in turf sod production areas in Korea.

Report on Zorka sp. (Homoptera: Typhlocybinae) as a pest of persimmon (Diosprosi kaki) in Korea.

A leafhopper, Zorka sp. was collected from a persimmon (Diospyrosi kaki, cv SangjuDungsi) orchard in Sangju, Gyeongsangbuk-do, Korea on 15 June, 2008. This leafhopper gave a serious damage to persimmon leaves, being a new pest to persimmon. This leafhopper was tentatively identified as Zorka sp., which has not been recorded in the science. White spots of

A Survey on Diseases and Insect Pests in Sweet Persimmon Export Complexes and Fruit for Export in Korea

Between 2010 and 2012, diseases and insect pests of sweet persimmon were surveyed at sweet persimmon export complexes and non-export orchards in Suncheon, Jeonnam Province; Jinju, Changwon (Dongeup and Bukmyeon), and Gimhae, Gyeongnam Province; and Ulzu, Ulsan. The following diseases were found in the sweet persimmon orchards: angular leaf spot (Cercospora kaki), anthracnose (Colletotrichum gloeosporioides and Colletotrichum acutatum), circular leaf spot (Mycosphaerella nawae), powdery mildew (Phyllactinia kakicola), and gray mold (Botrytis cinerea). Circular leaf spot was the most frequent and serious disease, and C. gloeosporioides and C. acutatum were found on fruits. Thirty-three insect pest species that belonged to 32 genera of 20 families in 5 orders were found in the sweet persimmon orchards; the two-spotted spider mite, Tetranychus urticae, was also found in the surveyed orchards. Apolygus spinolae, Pseudaulacaspis cockerelli, and Adoxophyes orana were widely found in the surveyed orchards; Spodoptera litura and Homona magnanima were also recorded. Damage by insect pests was low, and the quarantine insect pests peach pyralid moth (Dichocrocis punctiferalis) and persimmon fruit moth (Stathmopoda masinissa) were rarely or not found in the sweet persimmon export complexes. In addition, other quarantine insect pests, such as persimmon false spider mite (Tenuipalpus zhizhilashviliae) and Japanese mealybug (Planococcus kraunhiae), were not detected. These quarantine insect pests were also not found in the sorting places, storage houses, and fruits for export; however, scale insects and two-spotted spider mites were found at a low rate. Although anthracnose (C. acutatum) infested fruit was found in the storage houses, only one in Jinju and Gimhae.

Occurrence and damage of Japanese gall-forming thrips, Ponticulothrips diospyrosi Haga et Okajima (Thysanoptera: Thripidae) in persimmon orchards.

Occurrence of Japanese gall-forming thrips, Ponticulothrips diospyrosi was surveyed from 143 orchards at 11 cities or counties in 6 provinces, Korea from 2008 to 2009. Occurrence of P. diospyrosi was not observed from Jeju (4 persimmon orchards) in Jeju-do and Wanju (12 persimmon orchards) in Jeollabuk-do. However, P. diospyrosi occurred newly in the orchards in Sanchung, Gyeongsangnam-do and in Gangreung, Gangwon-do. Rate of damaged orchards by P. diospyrosi in Gumi, Mungyeong, Sangju and Euseong in Gyeongsangbuk-do (73.3%) was higher than that of in Gyeongsangnam-do or Youngdong areas in Chungcheongbuk-do. A maximum rate of damaged trees by P. diospyrosi was 23.5% in Gumi, while the damage was lower in Sancheong and Jinju representing 0.2 and 1.6%, respectively. Rate of damaged leaves by P. diospyrosi was the highest in Sangju (0.12%). P. diospyrosi occurred between and and between to . Persimmon orchards close to mountain were more damaged by P. diospyrosi. Edge parts of persimmon orchards were more damaged by P. diospyrosi than inner parts, especially in orchards close to mountain. Also, the middle and lower parts of tree canopy were more damaged by P. diospyrosi than the upper parts of canopy.

Differences of Wood Vinegar Ingestion and Exercise Training on Blood Lipids, MDA, and SOD Activities in Rats

The purpose of this study is to identify the effects of exercise training and oak tree wood vinegar ingestion on the blood lipids and antioxidant activities of rats. The subjects were 28 Sprague Dawley male rats, and they were assigned into four groups (n=7, respectively): the control group (CON), the exercise group (EXE), the vinegar ingestion group (VIN), and the vinegar ingestion and exercise training group (VINEXE). The diet was based on high fat and oral administration of oak tree wood vinegar. The rats that were not given oak tree wood vinegar were given the same amount of distilled water orally in order to maintain the same level of stress. They were exercise trained on motor-driven treadmills during a four-week session. Weight changes in the VINEXE were significantly inhibited in the later period of exercise, when compared to the CON (p＜0.05). Fat increase was significantly suppressed in VIN and EXE (p＜0.05), and a synergistic effect was discovered in the VINEXE (p＜0.05). Glucose and ammonia levels were significantly reduced in the EXE, VIN, and VINEXE compared to the CON (p＜0.05). In blood lipids, TC and LDL-C were significantly enhanced in the EXE, VIN, and VINEXE compared to the CON (p＜0.05), while HDL-C was significantly improved in the EXE and VINEXE (p＜0.05). Liver MDA contents showed significant changes in each group (p＜0.05), and SOD activities were significantly enhanced in the VIN and the VINEXE when compared to other groups (p＜0.05). Therefore, oak tree wood vinegar ingestion with exercise training for four weeks may result in inhibition of weight gain, improvement of blood lipids, and inhibition of lipid peroxidation, contributing to health promotion.