• 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.

• Korean journal of applied entomology
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• v.33 no.3
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• pp.201-206
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• 1994

Trunk implantation method of phosphamidon 50% Lq.is commonly applied to control the pine needle gall midge (Thecodiplosis laponensts Uchida et Inouye) Since trunk implantaion is normally practiced during the late Spring, it is often difficult to accommodate necessay labor in mral area. As an alternative, aerial spraylng of less toxic ~nsecticide was designed. Usage of less toxic insecticide in the aenal control of pine needle gall midge can reduce the damage to forest ecosystem. The buproferin, one of the insect growth regulator, was selected at d~fferent rate of dilutions and the treatments effects ruere evaluated at different date and time When 50 t~mes diluted solution of buprofezin 40% SC was treated on different period, there was no significant difference in dficacies. the control efficacies of buproferin 40% SC was measured by occurrences (%) of gall formation of the pine needle gall midge using a ultra low volume (ULV) sprayer and the dilutions of 10X 30X and 50X of buprofez~n 40% SC gave efficacies. 72.4. 57.6 and 8.4, respectively.

• Journal of Sericultural and Entomological Science
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• v.24 no.1
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• pp.32-38
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• 1982

The study has been carried out to investigate a possibility to control the pine needle gall midge, Thecodiplosis japonensis Uchida et Inoue, by microbial pathogens as one of the microbial control measures. The samples were collected at Kocheon-Ri in the suburbs of Suweon city where were heavily damaged by this pest. Microorganisms were isolated from the both of diseased larvae and baiting method of soil microbes. In addition to, several species of the silkworm mucardine diseases were isolated for their infectivity of these fungi to the larvae of pine needle gall midge. Six species of fungi, Aureobasidium pullulans, Ascochyta sp, Verticillium psalliotae, Streptomyces sp., and two species of Aspergillus were isolated from the galls and soils, five species of muscardine diseases, Isaria farinosa, Spicaria pracina, Oospora destructor, Aspergillus flavus and A. oryzae were also identified from the silkworm corpse collected in the silkworm rearing farmers. Total of eleven species of fungi identified from the both of the larval of pine needle gall midge and silkworm larvae were tested for their pathogenecity to the larvae of pine needle gall midge. All of eleven species of fungi identified showed a considerable infectivity to the larvae. Twenty nine different kinds of bacteria were isolated from the both of diseased larvae and infested soils through the direct planting for the larvae and streaking for the corpse. The infectivity test is in progress. However two kinds of bacteria were recognized to be pathogenic to the larvae tested.

• The Korean Journal of Ecology
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• v.1 no.2
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• pp.66-71
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• 1977

The growth of red and black pines in Muan, Seochen, Gapyeong and Kochang areas was compared by means of the growth of annual ring width and stem analysis to study the process of damages caused by pine needle gall midge. Red pine forest of Seocheon area began to suffer by pine needle gall midge from 1961 and the damage was to becoming severe from 1967. The damage became so intense tha tmany forests are withering to death from spring of 1975. Black pine forest also began to suffer from 1973. Red pine forest of Muan area was supposed to be suffered from 1973. Red pine forest of Kochang area suffered by pine needle gall midge from 1967. It seems that the damage became severe from 1973 and that black pine forest was also badly damaged from that time. Red pine forest of the control plot, Gapyeong area, began to suffer from 1967 and it also became intense from 1973. Although the areas of Seocheon, Muan, Kochang, and Gapyeong are different from each other in terms of locality and the infitration period of pine needle gall equally from 1967 due to mass development of population or other factors and the damage became more intense from 1973. Black pine forest was also badly damaged from that time. Black pine seems to be stronger in insect resistant than red pine. This can be justified by the fact that it began to suffer belatedly in each area and the degree of damage is moderate. The damage of Seocheon area is the severest following Kochang. Muan area is relatively moderate but the forest becoming decrease in growth.

• 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.

• 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.

• 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).

• 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.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.