• 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.

• Korean journal of applied entomology
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• v.19 no.1 s.42
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• pp.35-38
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• 1980

A new species of Platygasteridae, Inostemma hockpari (n. sp.) is described from Korea. This new species is an important biological control agent of the pine gall midge together with Inostemma seoulis, Platygaster matsutama and Inostemma matsutama (Collected in Jinhae by the author) in Korea.

• Journal of Korean Society of Forest Science
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• v.95 no.3
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• pp.256-260
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• 2006

This study was conducted to investigate the effect of parasititoids on the density-fluctuation of the pine needle gall midge, Thecodiplosis japonensis. The density of T. japonensis and its parasitoids was observed by emergence trap in pine forest in Namsung-dong, Keumho-eup, Youngcheon-shi, Kyeongsangbuk-do, Korea, from 1986 to 2005. After 1987, density fluctuations of adults pine needle gall midge and its parasitoids showed similar trends and density of parasitoids was dependent on density of host population. Sex ratio of the pine needle gall midge, T. japonensis, was female-biased and had some variations in according to years. These trends were similar to those of parasitoid populations and sex ratio of Inostemma seoulis was more female-biased than that of I. matsutama. T. japonensis adults emerged in the field from May 16 to July 27 and the peak of emergence was between late May and early June. The adults of Inostemma matsutama emerged from May 16 to June 11 (peak between late May and early June), whereas those of Inostemma seoulis emerged from June 9 to July 27 (peak: late June).

• Korean journal of applied entomology
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• v.34 no.4
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• pp.368-372
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• 1995

To develop a microbial pesticide for the control of pine gall midges. Thecodiplosis japonensis, entomopathogenc fungi were isolated from 233 soil samples in the damaged region of Thecodiplosis japonenesis, and identified with Beauveria spp. 29 strains and Paecilomyces spp. 2 strains. The morphology of entomopathogenic fungi was observed by scanning electron miroscope. In addition, the toxicity of entomopathogenic fungi was observed by scanning electron microscope. In addition, the toxicity of entomopathogenic fungi isolated from soil samples was determined by bioassay against Thecodiplosis japonensis larvae. The result showed that toxicity of relatively pathogenic strains, Beauveria spp. SFB-168-2 was 82.9%, suggesting that Beauveria spp. SFB-168-2 is effective entomopathogenic fungi for the control of pine gall midges.

• Journal of Korean Society of Forest Science
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• v.85 no.2
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• pp.244-250
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• 1996

The objectives of this paper were to study the existence of resistant substance to pine gall midge from needles of Pinus densiflora, P. thunbergii, P. virginiana, and P. thunbergii${\times}$P. virginiana, and also to investigat whether terpenoids, fragrant substance contained in those species seduce or evade imago of pine gall midge to oviposit. Also, terpenoids and phenolic compounds were bioassayed on larva. The results are follows. Adults of pine gall midge oviposited indiscriminately all investigated pine species, while gall formation rate by pine gall midge showed 0% in Pinus virginiana, 9% in P. thunbergii${\times}$P. virginiana, 22% in P. thunbergii. It is suggested that young larvae is necrotized by resistant substance in the needles of P. virginiana. This results might mean that fragrant substance, terpenoids, extracted from pine species is not seducible or evadable substance. Larvae of pine gall midge placed on terpenoid and resin were not necrotized. The necrosis rate of larvae of pine gall midge cultivated in the solution of phenolic compounds extracted from needles of P. virginiana, salicylic acid and chitinase showed 89, 92, and 86% respectively. And necrosis rate was 56 and 59% in phenolic compounds extracted from P. densiflora and gallic acid respectively. So, it is postulated that phenolic compounds contained in needles of P. virginiana, salicylic acid and chitinase are resistant substance to pine gall midge.

• Korean journal of applied entomology
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• v.4
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• pp.55-58
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• 1965

This is a report that we investigated the distribution of Pine Gall-midge (Thecodiplosis japonensis UCHIDA et INOUYE) along the main roads in the vicinity of Seoul. 1. The Pine Gall-midge around the districts of Seoul spread to East-Northern direction, Kwang-Ju, Yang-Su, Su-Pa, Bong-il-Chun and Ko-Chon etc. 2. The factors responsible to the dispersal of Pine Gall-midge seemed to be with the direction of the wind during the period of adult emergence. 3. The parasitic rate of Isostasius seoulis on the Pine Gall-midge was very low except $13.6\%$ at Su-Pa district.

• Journal of Korean Society of Forest Science
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• v.9 no.1
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• pp.49-54
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• 1969

As one phase of the biological control of the Pine gall-midge, Thecodiplosis japonensis Uchida et Inouye, this investigation on birds as a vertebrte predator of the larvae of Pine gall-midge was carried out. Species of the birds as predator, number of the larvae as prey for individual birds and seasonal trends of the prey quantity were studied. This work was carried out during the late fall of 1967 and 1968 at Kwang Nueng Forest which is one of the heavily infested districts by the Pine gall-midge. 1. Korean Great-Tit, East China Marsh-Tit, Quelpart Coal-Tit, White-headed Long-tailed Tit, Varied Tit, Kamchatkan Rustic Bunting, Yellow-thrated Bunting, Chestnut Bunting and Korean Goldcrest were found to be the predator of the larvae of Pine gall-midge. 2. The average number of larvae as prey found from individual predator bird species were approximatly 108 for Kamchatkan Rustic Bunting, 17-64 for East China Marsh-Tit, 25-28 for Korean Great Tit and 36 for Quelpart Coal Tit. 3. The seasonal change in the number of the larvae which fell into the ground affected the seasonal trends of the prey quantity of the predator birds 4. Among the 380 birds examined, 157 birds were found to attack the larvae of Pine gall-midge.

• 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.7 no.1
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• pp.40-44
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• 1968

1. The larvae of the pine gall-midge begin to grow slowly from early July but grow rapidly from September. 2. The number of larvae in the galls does not decrease during the feeding period. 3. Pine needles infested by pine gall-midge cease to grow as soon as the gall starts to form. 4. In Seoul district the effective felling season of the pine trees for the Control of the pine gall-midge seems to be around 20th September when the size of larvae reaches 1.4-1.5mm in length. 5. The stratification and direction of the Crown, and the length of new shoot had no effect on the degree of infestation by pine gall-midge. However the degree of infestation differed among the trees of different ages as well as at the different levels of the mountain.

• Journal of Korean Society of Forest Science
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• v.62 no.1
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• pp.87-95
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• 1983

The effects of the pine needle gall midge, Thecodiplosis japonensis, on the growth of the Korean red pine, Pinus densiflora, were examined for the natural forest stands at nine locations: Seocheon-gun, Boryong-gun, and Hongseong-gun in Chooncheongnam-do, where consequence of the infestation had been different. To estimate the economic threshold level of the pine needle gall midge, the growth impacts due to the insect were examined with terminal shoot growth, and cambial growth by analyzing the growth horizontally and vertically. The results obtained are as follows: 1) In general, the growth impacts of the red pine trees were significant for the five consecutive years since damage had occurred, and its maximum retardation was shown in the second and the third years. 2) Simultaneous retardation occurred in both terminal and cambial growth of the tree, probably due to cumulative characteristics of the feeding behaviour. 3) Strong correlation was found between terminal and cambial growth of Korean red pine and this was true for the trees infested by pine needle gall midge. Thus retardation in cambial growth due to the insect may be estimated with that in terminal growth. 4) Infestation was greater on slope facing north than south even though the history of the infestation had been similar. 5) The stem volume of 13-year-old, infested Korean red pine was reduced by more than 75-85%, compared to same aged, uninfected pine in yield table. Thus, much longer period is required to recover the normal growth.