• Korean journal of applied entomology
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• v.36 no.2
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• pp.150-155
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• 1997

Distribution of pine needle gall midge infestations was analyzed from data collected in young Japanese red pine stands during 1992, and 1995-1996 in Kangwon-do. No significant differences in percentages of infested needle pairs were found among trees and between terminal and lateral shoots within a tree. However, the mean percentages of infested needle pairs increased significantly from the lower crown to the upper. Percentages of infested needle pairs on sample units, consisting 1 terminal and 2 lateral shoots, in the midcrown were best predictors of whole-tree percentages than were other crown levels. Therefore, a sample unit consisting of 1 terminal shoot and 2 lateral shoots per branch were fixed from the midcrown level. Number of tree and sample unit combinations needed to estimate pine needle gall midge infestations with given two levels of precision were determined.

• 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.

• Applied Biological Chemistry
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• v.23 no.3
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• pp.189-197
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• 1980

Effect of monoterpene composition in pine needles on the susceptibility to pine gall midge (Thecodiplosis japonensis Uchida et Inouye) has been pursued. The pines studied include 5 susceptible and 2 resistant species. Also included were severely damaged or unaffected P. densiflora in the pine gall midge affected region. From the needles of the pine trees, 9 monoterpenes were identified by GLC. No correlationship, was found to hold in the monoterpene composition between pine gall midge susceptible and nonsusceptible pine species. Concentrations of limonene, however, gradually increased following oviposition in the unaffected P. densiflora while the concentrations of the monoterpene remained constant in the damaged P. densiflora. Effect of high limonene concentration in the needles of P. densiflora is discussed as a possible factor inducing resistance toward the pest in the unaffected Pinus densiflora.

• The Korean Journal of Ecology
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• v.6 no.1
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• pp.33-44
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• 1983

Vegetatiion structure and population dynamcis of pine needle gall midge were investigated from 1980 to 1982 at the southern part of Palgong mountain near Daegu. The results of investigation at the areas of A (pure stand), B(30% mixed forest) adn C(60% mixed forest) were as follow; Vegeation of 3 areas were not classified by the species diversity, but by the unequal distribution of Alnus hirsuta, Robinia pseudo-acacia, Lespedeza cyrtobotrya, Quercus variabilis and vitality of Pinus densiflora at the area C was low, due to shadow by broad-leaf trees. Soil environmental factors at 3 areas not characteristic, but the average of humus contents showed high significance and the order was A

• 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.21 no.3 s.52
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• pp.163-166
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• 1982

The pine needle gall midge, Therodiplosis japonensis Uchida et Inouye, is the most important insect pest. It requires two different habitats for the development; on trees and under the ground. The habitat specific mortality rates ere $30\~40\%,\;and\;50\~60\%$ for the respective habitats. The key developmental stage is the prepupa, and the key mortality factor is the moisture contents of the soil and its variability. Since the insect is an exotic, the population status is the periphery and in the source of infestation are considerably different. Such a difference in habitats and the population status of the insect should be considered in relation to suppression of the insect. The control strategies should be directional and rational based on the reality of the pest status. There have been substantial information on the control methods of the pine needle gall midge, and each control method has an important place, but none has always provided a satisfactory solution to the many problems associated by this insect. These methods should be applied to a system based on the ecology of the insect. There should be continued support for directed effort on the development of operational management systems for the insect: specifically, estmation of the critical economic injury level, and of the absolute density of the insect.

• Korean journal of applied entomology
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• v.27 no.3
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• pp.144-148
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• 1988

Using scanning electron microscope, we studied the adult genital segments of pine needle gall midge, Thecodiplosis Japonensis, Uchida et Inouye Male: There were two pairs of hypoproct a pair of claspettes and aedeagus, Hypoproct were surrounded with many setae and sensilla. Clasperres which was projected below hypoproct was composed of two aegments and had many sensilla Aedeagus was long and flattened and possesed some sensilla at the terminal. Female :Ovipositor was segmented into three parts. Each segment had a different externla sturcture; particularly, the 2nd one was covered with reversed boat-like attachments and did not show any sensillum.

• Applied Biological Chemistry
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• v.20 no.1
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• pp.81-87
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• 1977

Resistant and susceptible pine (Pinus thunbergii, Parl) trees to pine gall midge (Thecodiplosis japonensis, Uchida et Inouye) were selected and monoterpene composition in one year old branches, shoots and needles of both groups have been analysed by GLC. The results are summarized as follows; 1. Monoterpene composition in either one year old branches or shoots were not affected by their directions (North or South). 2. Major monoterpenes in one year old branches were ${\alpha}-pinene,\;{\beta}-pinene$, myrcene, limonene, ${\beta}-phellandrene$ and terpinolene. 3. In addition to ${\alpha}-pinene$, camphene, ${\beta}-pinene$, myrcene, ${\Delta}^3-carene$, limonene, ${\beta}-phellandrene$ and terpinolene, several less volatile components which appear to be monoterpenes were also present in shoots and needles. 4. Compared with the susceptible pine, the resistant tree was found richer in limonene composition. 5. ${\beta}-Pinene$ composition in the resistant pine was less than that in the susceptible pine. 6. The difference in the composition of limonene or ${\beta}-pinene$ between two groups of pine trees was discussed in relation to the resistance to pine gall midge.

• 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.

• Journal of Korean Society of Forest Science
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• v.61 no.1
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• pp.20-26
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• 1983

Some aspects of the change in the rate of gall formation on the red pine, Pinus densiflora Siebold et Zuccarini, by the pine needle gall midge, Thecodiplosis japonensis Uchida et Inouye, were investigated at the coastal area in Chung Nam-Do from 1977 to 1982, and were analyzed with the nationwide survey data for 2 years from 1980 to 1981. The results obtained were as follows; the gall formation rate in several areas was compared between two consecutive generations. Four regression equations were established, with X as the gall formation rate in N year and Y as that in (N+1) year: 1) Y=11.2+1.15X (r=0.833) for the stands facing north on the phase of insect population increase, 2) Y=14.3+0.82X (r=0.739) for the stands facing south on the phase of population increase, 3) Y=7.3+0.46X (r=0.478) for stands facing north on the phase of population decrease and 4) Y=11.4+0.19X (r=0.086) for stands facing south on the phase of population decrease. After invasion of the pine needle gall midge into a red pine forest, gall formation rate increased for 6 consecutive generations and then decreased to low level within a period of another 6 years.