• Journal of Korean Society of Forest Science
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• v.85 no.3
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• pp.372-380
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• 1996

This study was carried out to study the resistant substances to pine needle gall midge and seasonal variation of phenolic compounds in pine needles among susceptible and resistant species to pine needle gall midge. Free and water soluble phenolic compounds contained in pine needles showed seasonal variations among pine species. But, catechol, vanillic acid and syringic acid including phenolic compounds showed no variation between pine species, even the amount of those component varied by the seasons. Salicylic acid in pine needles showed 140ppm in Pinus virginiana, 35ppm in Pinus thunbergii and 72ppm in hybrid pine, Pinus thunbergii${\times}$P. virginiana, but traces in Pinus densiflora on May and June, hatching season in larvae of pine needle gall midge. There was high level of salicylic acid in resistant species to pine needle gall midge but traces in susceptible species. As our previous researches, the necrosis rate of larvae of pine needle gall midge showed high level on the solution of phenolic compounds extracted from needles of P. virginiana and salicylic acid, and there was no gall formation in P. virginiana, so that salicylic acid in pine needles seems to have relation with those results. Therefore, it is estimated that salicylic acid is resistant substance to pine needle gall midge.

• Research in Plant Disease
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• v.14 no.3
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• pp.159-164
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• 2008

Crown gall of rose (Rosa hybrida) was observed in greenhouse during 2003-2007. The average disease incidence was up to 38.1 % and was more severe in hydroponic culture as compared to soil culture. The typical gall symptom occurred mainly on the root, crown, or both, and resulted on poor rooting, growth retardation and yield loss. The reduction rate of rooting influenced by crown gall was 57.5% as compared to healthy plants on nursery stock. The location of gall formation in the plant influenced growth vigor resulting in symptoms such as poor shooting. Healthy plants produced 19.1 flowers/$m^2$, while diseased plants produced 9.5 flowers/$m^2$ during the same cultivation period. Moreover, the number of days to flowering was longer for the diseased plants than for healthy plants - 51.2 days and 39.8 days for first harvest, and 60.6 days and 52.1 days for the second harvest, respectively. Conclusively, infection on the basal stem caused serious loss of the number of shoot formation; yield loss of cut flower was 38.7% due to crown gall infection and delay of harvesting time about 8-10 days.

• Korean Journal of Plant Resources
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• v.19 no.5
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• pp.598-601
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• 2006

In order to prevent chestnut from damaged by the chestnut gall wasp, Dryocosmus kuriphilus, a sprinkler system was installed on the chestnut orchard. Such a test was conducted at Sanchung-gun, Kyeongnam province, Korea in 2003 and 2004. Insecticide of carbaryl 50% WP, x1,500 was sprayed at every day and two-day intervals during the period of D. kuriphilus adult occurrence by sprinkler system. The chestnut gall wasps generally emerged for about 35 days from the middle June to the middle July, and peak emergence was 5 days of early July. Crown application of carbaryl by sprinkler system was found to be highly effective for control of the chestnut gall wasp. Gall formation rate of chestnut were 3.0 and 12.8% on average with crown insecticide spraying at every day and two-day intervals, while 82.9% when not treated. Control effectiveness of this insecticide spraying was 96.4% and 84.6%, respectively.

• The Korean Journal of Pesticide Science
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• v.5 no.3
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• pp.50-53
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• 2001

Severe crown gall disease was occurred in green house cultivating rose in Jinchen, Chungbuk recently. Although it causes problem on rose cultivation, the growers do not have many choices of control measures for the disease now. Agrobacterium radiobacter K84 has been known as a strong antagonist against A. tumefaciens, a pathogen causing crown gall disease, and used as a biopesticide for crown gall in many countries since it had been introduced in 1972. We tested control activity of A. radiobacter K84 for the crown gall disease on rose. Spray of A. radiobacter K84 suspension on above ground of rose either before or after pathogen spray reduced size and fresh weight of galls significantly. Size and fresh weight of galls on roses inoculated with pathogen either before A. radiobacter K84 spray (pathogen-K84 treatment) or after A. radiobacter K84 spray(K84-pathogen treatment) were 4 to 5% of those of galls on roses inoculated pathogen only. Disease incidence of plants inoculated pathogen only was 85% whereas disease incidence of pathogen-K84 or K84-pathogen treatments were 6.7% and 5.0% respectively. Dipping of roots of rose in suspension of A. radiobacter K84 was also reduced size of galls and diseased rate significantly. These results indicate that A. radiobacter K84 is effective in the prevention of gall formation by A. tumefaciens and it can be used to control of crown gall disease of rose.

• Korean journal of applied entomology
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• v.40 no.4
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• pp.301-307
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• 2001

The pine needle gall midge (PNGM), Thecodiplosis japonensis Uchida et Inouye, is a serious pest in pine forests in Korea. Since the first report of PNGM infestation in Korea in 1929, the infestation area has been expanded gradually. In 1975 the distribution of PNGM and its parasitoids were surveyed throughout several infested areas in Korea. Annual survey has been made for the rates of gall formation by PNGM and parasitism by its parasitoids at the monitoring sites including newly infested area in 1975 since 1980. These data were used to examine the relationship between PNGM and its parasitoids for newly invaded areas. The gall forming rate of PNGM and the parasitism by the parasitoid were 34.8 and 1.9% in 1975, respectively, while the gall forming rate and the parasitism were 20.7 and 8.9% in 1985, respectively. The relationships of densities between PNGM and its parsitoid were weak in the early stage of dispersion, but the density of parasitoid was with an asymptotic increase along with PNGMs density increase during the observation period for 10 years.

• Journal of Korean Society of Forest Science
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• v.87 no.3
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• pp.475-482
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• 1998

9 species of parasitoids emerged from chestnut gall samples collected at Chunchon, Kangwon in June to July 1995 - 1997, and 8 species emerged from gall samples at the 5 investigation sites in December 1997. The primary parasitoids among them were Torymus sinensis, Torymus geranii, Sycophila variegata, Megastigmus nipponicus, Megastigmus maculipennis, Eurytoma brunniventris, Ormyrus flavitibialis, Ormyrus punctiger, Eupelmus urozonus, while the secondary parasitoids were Torymus geranii, Sycophila variegata, Eupelmus urozonus, Eupelmus sp., Eurytoma setigera, Ormyrus punctiger. Torymus sp.. Some of secondary parasitoids were facultative hyperparasitoids, parasitizing the gall wasp as well as primary parasitoids, Among these natural enemies, Torymus sinensis was dominant at all sites. At Chunchon, the rate of gall formation showed decreasing tendency as the function of generation and the parasitism rate of Torymus sinensis showed increasing tendency gradually. But the rate of parasitization of the secondary parasitoids(Sycophila variegata, Eupelmus urozonus, Torymus geranii, Ormyrus puntiger) ranged from 4.0% to 10.5%. The mortality was high during June to October which was immature stage of Torymus sinensis, and mainly caused by secondary parasitoids. Torymus sinensis emerged from April to May and the estimated dates of 50% emergence was 21st April. The estimated dates of 50% emergence for the other, Sycophila variegata, Eupelmus urozonus, Torymus geranii, and Ormyrus puntiger were 25th April, 30th April, 4th May, and 22nd May, respectively.

• Korean journal of applied entomology
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• v.56 no.1
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• pp.77-81
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• 2017

The results from our investigation showed differences in pine needle damage by Thecodiplosis japonensis Uchida et Inouye and indicate serious environmental pollution caused by a petrochemical industrial complex. The gall formation rate by T. japonensis near the industrial complex was 47.94% compared to 9.94% in the site farthest from the complex. The average length of pine needles damaged by T. japonensis near the industrial complex and farthest site were 4.5 cm and 4.9 cm, respectively. The average number of larvae in pine needle galls near the industrial complex and farthest site were 3.4 and 2.4, respectively. The average body length and width of fullgrown larvae near the industrial complex were 2.40 mm and 0.7 mm, respectively, whereas larvae in the site farthest from the complex were 2.45 mm in length and 0.71 mm in width.

• Journal of Korean Society of Forest Science
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• v.94 no.1 s.158
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• pp.21-25
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• 2005

In order to prevent the pine mushrooms, Tricholoma matsutake, from being damaged by the pine needle gall midges, Thecodiplosis japonensis, and thereby, to increase their production and improve their quality, a sprinkler system was installed on the mushroom field. A low-concentration insecticide (deltamethrin 1% EC, x2,000) was sprayed once at insects' most active time every day during the period of insects' adult occurrence and thereafter, the irrigation by ground water spraying was periodically enforced. Such a test was conducted at Yangyang-Gun, Kwangwon-do, Korea for 2 years from 2000 through 2001. The pine needle gall midges generally emerged for about 40 days from late May to early July. 50% emergence of them was about June 6, and peak emergence (more than 80%) was early or mid-June. Gall formation rate was 3.5% on average with this ground insecticide spraying, while 51.3% when not treated. Control effectiveness of this insecticide spraying was 92.3%, which was higher than 82.5% by the conventional injection of insecticide into tree stems. Pine mushrooms emerged for about 35 days from mid-September through earlier October, and around 80% of them did for about 15 days from late September through early October. As a result of the periodic ground water-spraying (30 mm per week) for 2 months (from August to October), the production of mushrooms increased by 74.3% (110% in terms of weight), with their quality improvement. The mushrooms produced from the treated stand by the spraying system were priced 8,670,000 wons per hectare, and thus, the net income deducting the facility and management cost was 4,310,000 wons, about 5% higher than value from the control stand. It was analyzed that this treatment was significantly cost effective when the facilities are used more than 5 years.

• The Plant Pathology Journal
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• v.19 no.3
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• pp.138-142
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• 2003

Soil amendments with oriental herbal medicines such as fruit of Anethum graveolens, flower buds of Syzygium aromaticum, rhizome of Cnidium officinale, rhizome of Coptis chinensis, root bark of Paeonia suffructicosa, stem bark of phellodendron amurense, and stem bark of Cinnamomum cassia at the rate of 0.2％ (weight by volume of soil) significantly reduced Meloidogyne incognita infection (root gall formation) of tomato seedlings compared with the control. The most effective treatments were root bark of p. suffructicosa and stem bark of C. cassia as they gave minimum numbers of galls on tomato roots (4.7% and 8.9%, respectively, relative to control) as compared to other treatments. Another study with root bark of p. suffructicosa and C. cassia at different application doses also showed consistent results in reducing gall number. The control efficacy decreased as the application doses were lower-ed, indicating their dose-dependent control activities. These treatments significantly enhanced aboveground plant growths (total masses).

• Journal of Korean Society of Forest Science
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• v.32 no.1
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• pp.16-20
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• 1976

Employing 7-15 resistant and 8-15 susceptible Japanese black pine (Pinus thunbergii Parl.) trees to pine gall midge (Thecodiplosis japonensis Uchida et Inouye) as samples, needle monoterpenes were analysed by GLC in January and June, and observation was made on the oviposition preference. Following results were obtained. 1. In January, the resistant trees showed higher contents of myrcene, limonene, ${\beta}$-phellandrene and terpinolene but lower contents of ${\alpha}$-and ${\beta}$-pinene and camphene compared to the susceptible trees. But in June, ${\alpha}$-pinene, camphene, limonene, ${\beta}$-phellandrene and terpinolene were higher and the content of ${\beta}$-pinene and myrcene were lower in the resistant trees than the susceptible trees. 2. The content of limonene was higher by the 6.8 percent and the content of ${\beta}$-pinene was lower by the 9.2 percent in the resistant trees than in the susceptible trees in June. 3. No preference for oviposition was found between resistant and susceptible trees. But in the resistant trees gall formation rate was quite lower than the susceptible trees. It was considered, therefore, that limonene and ${\beta}$-pinene content in the needle might be used as an indicator of the resistant Japanese black pine to the pine gall midge regardless of season.