• Title/Summary/Keyword: Termite

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Radial Variation in Selected Wood Properties of Indonesian Merkusii Pine

  • Darmawan, Wayan;Nandika, Dodi;Afaf, Britty Datin Hasna;Rahayu, Istie;Lumongga, Dumasari
    • Journal of the Korean Wood Science and Technology
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    • v.46 no.4
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    • pp.323-337
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    • 2018
  • Merkusii pine wood (Pinus merkusii) was extensively planted throughout Indonesia, where it is only indigenous in northern Sumatera, by the Dutch during colonial times. The demand for this wood species, especially in the domestic market, has increased notably, despite its limited durability regarding decay resistance. The purpose of this study was to investigate the occurrence of juvenile and mature wood on merkusii pine and to analyze its radial features from pith to bark based on density, shrinkage, static bending in modulus of rupture and modulus of elasticity, fiber length, microfibril angle, and durability. A segmented modeling approach was used to find the juvenile-mature transition. The graveyard test was performed to characterize the termite resistance from pith to bark of merkusii pine. The maturations were estimated to start at radial increments of 15 cm from the pith by fiber length and of 12 cm from the pith by microfibril angle. The projected figures for the proportion of juvenile wood at breast height were around 65%. The results also indicate that the pine wood was $0.52g/cm^3$ in density, 1.45 in coefficient of anisotropy, which indicates its good stability, 7597 MPa in modulus of elasticity, and 63 MPa in modulus of rupture. Natural durability against subterranean termite of the merkusii pine wood was rated to be grade 4 to 0 from pith to bark. However, after being treated by Entiblu and Enborer preservatives, its rating increased to grade 10 to 9.

A Simulation Model for the Study of the Territorial Behavior of Subterranean Termites (흰개미 테리토리행동 연구를 위한 시뮬레이션 모델)

  • Jeon, Won-Ju;Lee, Sang-Hee
    • Journal of the Korea Society for Simulation
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    • v.21 no.2
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    • pp.1-9
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    • 2012
  • Subterranean termites forage by constructing tunnel networks in soil and encounter food resources during tunnel excavation. Some species of termites can travel up to 150 m underground. They often travel to the surface to find wood cellulose to feed their colony, which in turn causes extensive damage to wooden architecture, such as timber-frame houses. This type of damage has been constantly increasing along with global warming because higher temperatures provide an ecological niche for termites. The damage is closely related to termite territory size and distribution. Recently, as a way to research termite control, the necessity of a mathematical model to simulate termite territory formation in relation to damage has increased. So far, however, few studies have been conducted on the development of a model because it is difficult to quantify or characterize the relationship between territorial behavior and field conditions including complicated environmental factors. In the present study, we suggest a simulation model of the territoriality of the Formosan subterranean termites, Coptotermes formosanus (Shiraki), and Reticulitermes flavipes (Kollar), based on empirical data. The model consists of 2 procedures. One describes tunnel network growth for each colony, and the other represents territoriality based on tunnel-tunnel interactions between different colonies. Using the model, we show changes in territorial competition according to the termination probability of tunnel growth.

MT surveys near Century Zinc Mine, NW Queensland, Australia (호주 Century 아연 광산에서의 MT 탐사)

  • Lee, Tae-Jong;Lee, Seong-Kon;Song, Yoon-Ho;Cull, James
    • Geophysics and Geophysical Exploration
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    • v.10 no.4
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    • pp.345-352
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    • 2007
  • Two-dimensional (2D) MT surveys near the Century mine in Australia have been performed with very far remote reference in Esashi, Japan (RR_ESS) as well as Gregory Downs (RR_GREG), which are roughly 6,400 km and 80 km apart from the survey area, respectively. Good quality of MT data could be obtained by remote reference processing with RR_GREG, while the coherency of magnetic fields between field sites and RR_ESS was not sufficient to be used as remote data. Both 2D and 3D inversion of 2D profile data represented the general geological structure beneath the survey area. The main target of the survey, Termite Range Fault, appeared as a boundary between a conductive block to the north and a resistive block to the south in the reconstructed resistivity section, and is inclined slightly to the north-east direction.

Expression Patterns of Odorant-Binding Proteins (OBPs) in a Termite (Reticulitermes speratus) (일본흰개미 (Reticulitermes speratus)의 Odorant-Binding Proteins (OBPs) 발현 양상)

  • Ra, Jong-Bum;Kim, Jae-Kyung;Kim, Gyu-Hyeok
    • Journal of the Korean Wood Science and Technology
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    • v.33 no.1 s.129
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    • pp.1-6
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    • 2005
  • This research was performed to investigate the expression patterns of odorant-binding proteins (OBPs) migrating hydrophobic semiochemicals such as pheromone to the olfactory receptors in a termite (Reticulitermes speratus). Antennas and legs were cut from soldier and worker termites, respectively, and RT-PCR were conducted to investigate the existence of the OBPs reported up to now. Blast search suggested that the OBPs obtained were highly homologues of the OBPs reported. In worker termites, OBP-1 was expressed in both antennas and legs, OBP-2 and OBP-3 were observed only in antennas. And in soldier termites, OBP-1 was shown in both antennas and legs, OBP-2 were not observed, and OBP-3 was found in both antennas and legs. The differences of expression patterns of OBPs between worker and soldier termites may be explained by their specialized peculiarity.

Elizabethkingia miricola BM10, a New Symbiotic Bacterium Isolated from the Hindgut of the Termite Reticulitermes speratus KMT001

  • LEE, Dongmin;KIM, Young-Kyoon;KIM, Yeong-Suk;KIM, Tae-Jong
    • Journal of the Korean Wood Science and Technology
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    • v.47 no.6
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    • pp.692-699
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    • 2019
  • Elizabethkingia miricola BM10, a symbiotic bacterium, has been isolated from the hindgut of Reticulitermes speratus KMT001, a termite which occurs on Bukhan Mountain in Seoul, Korea. This strain demonstrated a symbiotic characteristic, in that it lacked endo-${\beta}$-1,4-glucanase activity, in a previous study. The major fatty acids of E. miricola BM10 were iso-$C_{15:0}$, iso-$C_{17:0}$ 3-OH, and summed feature 3 (iso-$C_{16:1}{\omega}7c/C_{16:1}{\omega}6c$). The content of iso-$C_{17:0}$ 3-OH was higher, while those of ECL 13.566, iso-$C_{17:11}{\omega}9c$, and summed feature 4 were lower than the other three type-strains of the Elizabethkingia genus. The 16S rRNA phylogenetic analysis confirmed that E. miricola BM10 is a new species. The whole genome of E. miricola BM10 was sequenced. The average nucleotide identity of strain BM10 as evaluated by pairwise comparison with E. anophelis R26, E. meningoseptica ATCC 13253, and E. miricola GTC 862 was shown to be 91.5%, 81.2%, and 94.29%, respectively. Based on our study results, E. miricola BM10 appears to represent a new strain of the genus Elizabethkingia.

Xylanolytic and Ethanologenic Potential of Gut Associated Yeasts from Different Species of Termites from India

  • Tiwari, Snigdha;Avchar, Rameshwar;Arora, Riya;Lanjekar, Vikram;Dhakephalkar, Prashant K.;Dagar, Sumit S.;Baghela, Abhishek
    • Mycobiology
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    • v.48 no.6
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    • pp.501-511
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    • 2020
  • Xylophagous termites are capable of degrading lignocellulose by symbiotic gut microorganisms along with the host's indigenous enzymes. Therefore, the termite gut might be a potential niche to obtain natural yeasts with celluloytic, xylanolytic and ethanologenic traits required for bioethanol production from lignocellulosic biomass. In this study, we cultured 79 yeasts from three different termites viz. Coptotermes heimi, Odontotermes javanicus and Odontotermes obesus. After suitable screening methods, we identified 53 yeasts, which belonged to 10 genera and 16 different species of both ascomycetous and basidiomycetous yeasts. Most yeasts in the present study represent their first-ever isolation from the termite gut. Representative strains of identified yeasts were evaluated for their cellulolytic, xylanolytic, and ethanologenic abilities. None of the isolates showed cellulase activity; 22 showed xylanolytic activity, while six produced substantial quantities of ethanol. Among xylanolytic cultures, Pseudozyma hubeiensis STAG 1.7 and Hannaella pagnoccae STAG 1.14 produced 1.31 and 1.17 IU of xylanase. Among ethanologenic yeasts, the strains belonging to genera Candida and Kodamaea produced high amount of ethanol. Overall, highest ethanol level of 4.42 g/L was produced by Candida tropicalis TS32 using 1% glucose, which increased up to 22.92 g/L at 35 ℃, pH 4.5 with 5% glucose. Fermentation of rice straw hydrolysate gave 8.95 g/l of ethanol with a yield of 0.42 g/g using the strain TS32. Our study highlights the gut of wood-feeding termites as a potential source of diverse yeasts that would be useful in the production of xylanase and bioethanol.

Resistance of Polystyrene-Impregnated Glued Laminated Lumbers after Exposure to Subterranean Termites in a Field

  • Dede HERMAWAN;Mahdi MUBAROK;Imam Busyra ABDILLAH;Yusuf Sudo HADI;Cossey YOSI;Aujchariya CHOTIKHUN;Rohmah PARI;Gustan PARI
    • Journal of the Korean Wood Science and Technology
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    • v.52 no.1
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    • pp.70-86
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    • 2024
  • Termites are a serious threat to wood-based products in Indonesia. This study investigated the termite resistant property of glulam made from polystyrene-modified wood. Three tropical fast-growing wood species, namely mangium (Acacia mangium), manii (Maesopsis eminii), and rubberwood (Hevea brasiliensis), were prepared for flat-sawn laminae. After getting air-dried condition, the laminae were impregnated with polystyrene using potassium peroxydisulphate as a catalyst followed by polymerization at 80℃. Polystyrene-impregnated and control glued-laminated lumbers (glulams) were manufactured, and solid wood was provided. Three wood species and three wood products with six replicates were exposed in a field in Bogor, Indonesia, for four months, and before the tests, their density and moisture content were measured. At the end of the field tests, the weight loss and protection levels of each test sample were determined. A completely randomized factorial design was used for data analysis. The weight percentage gains for mangium, manii, and rubberwood were 22.30%, 18.22%, and 10.44%, respectively. The results showed that manii belonged to low-density wood, whereas the other two woods were medium-density wood, and the moisture content was the ambient moisture content, typical of the Bogor area. Regarding weight loss and protection level, mangium was the most durable against subterranean termite attacks, followed by rubberwood and manii. Among the wood products, the polystyrene-impregnated glulam presented the highest durability, followed by the control glulam and solid wood. Therefore, mangium and rubberwood polystyrene-impregnated glulams are recommended for future product development.

Changes in Chemical Property of Soil Affected by Termites (Reticulitermes speratus kyushuensis Morimoto) in Korea (국내 흰개미(Reticulitermes speratus kyushuensis Morimoto)에 의한 토양의 화학적 특성 변화)

  • Seong, Se Ha;Kim, Keun Ki;Hong, Chang Oh;Park, Hyean Cheal
    • Journal of Environmental Science International
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    • v.26 no.6
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    • pp.789-795
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    • 2017
  • Termites (Isoptera) are classified into approximately 3,106 species. In Korea, only one species has been identified, which is Reticulitermes speratus kyushuensis Morimoto. The termite, a social insect, is known to play an important role in nutrient cycling of the ecosystem, although some species of termites are well-known pests attacking wooden structures or any plant materials. However, there is a lack of research about termites in Korea, including aspects such the taxonomy, physiology, and ecology of termites. This study was carried out to provide valuable basic data on the ecological role of termites in an ecosystem in Korea for the future studies. For the experiments, soil and termite samples were randomly collected from Mt. Hwajang located in Jikdong-ri, Eonyang-eup, Ulju-gun, Korea between October 5 and 30, 2015. Analysis results showed that there were no significant differences in soil chemical properties between the soil samples just after air-drying and one year elapsed without any treatment. The treated soil with termites showed significantly higher than the soil without termite treatment. Chemical properties of total nitrogen, organic matter, available phosphate, pH, Calcium(Ca), Potassium(K) and Magnesium(Mg) in soil treated with termites were $1.11{\pm}0.3gkg^{-1}$, $43.3{\pm}12.4gkg^{-1}$, $27.4{\pm}2.9mgkg^{-1}$, $4.56{\pm}0.2$, $0.82{\pm}0.2cmol_ckg^{-1}$, $3.18{\pm}1.4cmol_ckg^{-1}$, $1.73{\pm}1.1cmol_ckg^{-1}$, respectively. The values of soil property of without termite treatment were $0.56{\pm}0.1gkg^{-1}$, $30.5{\pm}3.1gkg^{-1}$, $24.0{\pm}4.7 mgkg^{-1}$, $4.09{\pm}0.1$, $0.71{\pm}0.2cmol_ckg^{-1}$, $2.88{\pm}1.5cmol_ckg^{-1}$, $1.30{\pm}0.7cmol_ckg^{-1}$, respectively. These results suggest that inhabitation of termites could improve soil chemical properties in an ecosystem.

Pest control managements for preservation of wooden cultural properties (목조문화재의 원형보존을 위한 충해 방제방안)

  • Lee, Kyu-Sik;Jeong, So-Young;Chung, Yong-Jae
    • 보존과학연구
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    • s.21
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    • pp.5-55
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    • 2000
  • The cultural properties are damaged by various causes according to the characteristics of material, the condition of preservation, and the period of time. Especially, biodeterioration makes lots of damages in organic properties than inorganic ones. The damages of wooden cultural properties by insects usually are caused by the three orders; Isoptera, Coleoptera, and Hymenoptera. As the result of investigation on the state of 141 buildings of wooden cultural properties in 1999, some of them were damaged by many kinds off actors; wasp, powder post beetle, cigarette beetle, termite, decay, and physical cracking. And it was found that the patterns of damages were related to species-specific habits of insects. There are several methods of pest control for the prevention of wooden cultural properties from damages caused by insects. Those are as follows; physical control, chemical control, biological control, and integrated pest management. When insects and fungi were detected at the wooden buildings, the fumigation is best treatment to stop biodeterioration. And then, wood materials also need to be treated with insecticidal and antiseptic chemicals to avoid a reinfestation, because the fumigant is volatile. The six commercial chemicals which are applied to the insecticidal and antiseptic treatment of wooden cultural properties were purchased to test their abilities. According to the comparative results of efficacy of them in laboratory, chemical D showed excellent efficacy in all items, including antiseptic and termiticidal items. The goal of these pest controls is to protect wooden buildings from insects and microorganisms. The most effective method used currently is chemical control(fumigation, insecticidal and anticeptic chemical treatment), but it has to be treated periodically to control pest effectively. Recently environmentally-friendly control methods such as bait system or biological treatments are replacing traditional barrier treatments using large amounts of chemicals. Especially, termite is a social insect which makes a colony. Although a building with fumigation treatment is safe for a while, once attacked building has a risk of damage by reinfestation of termite. Therefore, to control termites from damaged building, the entire colony including reproductives(queen and king) and larvae around buildings must beeliminated. Bait system can be used as a preventive measure in early detection of them through termites colony monitoring and baiting. It would be the most effective for termite control if bait system would be used together with the chemical controls.

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Effect of Heat Treatment Conditions on Color Change and Termite Resistance of Heat-Treated Wood (열처리 조건이 목재의 색상 변화 및 흰개미 저항성에 미치는 영향)

  • Ra, Jong-Bum;Kim, Ki-Bum;Leem, Kyung-Hun
    • Journal of the Korean Wood Science and Technology
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    • v.40 no.6
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    • pp.370-377
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    • 2012
  • This study was conducted to investigate the color change of heat-treated wood made of Korean pine (Pinus koraiensis S. et Z.), and lodgepole pine (Pinus contorta Dougl). The wood samples were heat-treated at 9 different treatment combinations of temperature (170, 180, 200, 220, and $230^{\circ}C$), and time (90, 120, 180, 240, 270 min.) set up by a response surface method. Wood color was measured using a colorimeter, and the samples were installed for evaluating the resistance of termite in the field test sites set up in Jinju. The lightness decreased with the increase of treatment temperature and treatment time. The color differences were evaluated by the method of National Bureau of Standards (NBS), and response surface models to predict the color change were fitted as a function of treatment temperature and treatment time. The $R^2$ values of the fitted models of heat-treated Korean pine and lodgepole pines were 0.92, and 0.88, respectively, showing the potential way for the prediction of color changes. Severe damage was found from the samples in the field test site, which means that the manufactured heat-treated wood did not show the termite resistance enough for the outdoor use.