• 보존과학연구
• /
• s.34
• /
• pp.84-99
• /
• 2013

There are more than 2,900 different species of termites in the world, and just there are 23 species in Japan. They caused more severe infestation compared with Korea. When a structure has become infested with termites, it is important that appropriate action must be taken: the chemical pest control (fumigation, soil termiticide treatment, bait system etc.) or the non-chemical pest control (low oxygen treatment, carbon dioxide treatment, high/low temperature treatment etc.). Especially, there were attempts to make practical protocol of various alternatives since the fumigant(methyl bromide) had been phased out in 2005 in Japan, and practically non-chemical methods would be effective alternatives for some cases, where the scale of infestation is small and limited and when long treatment is possible. But most of all, it is important that the process of pest control is made according to each species of termites with consideration for different characteristics of termites.

• Applied Biological Chemistry
• /
• v.43 no.1
• /
• pp.67-71
• /
• 2000

Termiticidal activities of Chamaecyparis obtusa were quantitatively evaluated, and the activity differences between supporting materials such as woodmeal and filter paper or between species were defined based on the termiticidal activity value(TAV). It was found that TAV was high in the following order ; C. obtusa>Litsea coreana>C. obtusa var. formosensis>Ternstroemia gymnanthera. In particular, termiticidal activity of C. obtusa heartwood was stronger by 5 to 9 times than that of other three species. Median survival dosage(MSD) of C. obtusa was 108.8 mg. In case of woodmeal or filter paper tests with C. obtusa, termiticidal activities were inversely proportional to logarithms values of an added sample weight and median survival time(MST). The difference of termiticidal activities between woodmeal and filter paper in the methanol extracts was small, but that in the neutral fraction was enormous as 3.21 times. However, termiticidal activity of neutral fraction was corresponded to 17 to 53% of original woodmeal, and 47 to 83% of termiticidal activity was considered as a loss in test process.

• Journal of the Korean Wood Science and Technology
• /
• v.48 no.1
• /
• pp.107-116
• /
• 2020

Termiticidal and fungicidal activities of wood vinegar from Cinnamomum parthenoxylon (CP) stem wood have been evaluated against Coptotermes curvignathus and wood rotting fungi (Schizophyllum commune and Fomitopsis palustris). The utilized CP wood vinegar was produced in the operating temperature range 250-300℃ pyrolysis. A no-choice test was applied for evaluating termiticidal activity with 33 active termites and antifungal activity using the agar media assay. The result showed that an increase in the concentrations of CP wood vinegar significantly raised the mortality of termite. CP wood vinegar showed high termiticidal activity, organic acids (acetic acid 42.91%, 3-butenoic acid 6.89%, butanoic acid, 2-propenyl ester 2.26%), and ketones (1-hydroxy-2-propanone 5.14%, 3-methylcyclopentane-1,2-dione 2.34%) might be largely contributed to termiticidal activity in addition to other minor components. Furthermore, CP wood vinegar exhibited significant inhibition of fungal growth. These data showed that CP wood vinegar was more toxic to white-rot fungi (S. commune) than brown-rot (F. palustris). The results suggested that phenolic compounds from lignin degradation were responsible for good antifungal activity.

• The Plant Pathology Journal
• /
• v.38 no.5
• /
• pp.449-460
• /
• 2022

This study was performed to reveal phenotypic characters and identity of symbiont bacteria of Nasutitermes as well as investigate their potential as antagonist of plant pathogenic fungi. Isolation of the symbiont bacteria was carried out from inside the heads and the bodies of soldier and worker termite which were collected from 3 locations of nests. Identification was performed using phenotypic test and sequence of 16S ribosomal DNA (16S rDNA). Antagonistic capability was investigated in the laboratory against 3 phytopathogenic fungi i.e., Phytophthora capsici, Ganoderma boninense, and Rigidoporus microporus. Totally, 39 bacterial isolates were obtained from inside the heads and the bodies of Nasutitermes. All the isolates showed capability to inhibit growth of P. capsici, however, 34 isolates showed capability to inhibit growth of G. boninense and 32 isolates showed capability to inhibit growth of R. microporus. Two bacterial strains (IK3.1P and 1B1.2P) which showed the highest percentage of inhibition were further identified based on their sequence of 16S rDNA. The result showed that 1K3.1P strain was placed in the group of type strain and reference strains of Lysinibacillus fusiformis meanwhile 1B1.2P strain was grouped within type strain and reference strains Paenibacillus alvei. The result of this study supply valuable information on the role of symbiont bacteria of Nasutitermes, which may support the development of the control method of the three above-mentioned phytopathogenic fungi.

• Journal of Forest and Environmental Science
• /
• v.39 no.1
• /
• pp.55-64
• /
• 2023

Properties of a lesser-used wood species were investigated to determine its potential for structural utilization. Trees of Delonix regia were felled and sampled at the base, middle and top and then sectioned to inner wood, middle wood, and outer wood for variation across the axial and radial directions. Hence, selected physical and mechanical properties as well as natural durability of D. regia along the radial and axial directions were examined. Obtained data were analyzed using analysis of variance (ANOVA) at α_0.05. There was no significant difference in the Moisture content (MC) of the wood but specific gravity (SG) decreased from base to top ranging from 0.35-0.44. Water absorption, volumetric swelling, and volumetric shrinkage range from 46.18-51.86%, 2.57-4.02%, and 2.26-3.96% respectively along the axial plane. The weight loss for graveyard exposure and accelerated laboratory decay test ranged from 25.14-48.00% and 32.02-44.45% respectively. Modulus of Rupture and Modulus of Elasticity values range from 29.42-72.68 Nmm² and 3,834.54-8,830.37 Nmm² respectively. The SG values has confirmed the species as a medium density wood and values of other properties tested showed that the wood is dimensional stable and moderately resistance to fungi and termite. Hence, it could be used for light construction purposes such as furniture and other interior woodwork.

• Journal of Life Science
• /
• v.18 no.2
• /
• pp.143-147
• /
• 2008

This study estimated the mound litter biomass and the nutrient content of mound litter in the two study plots in Durokoppin Nature Reserve, Western Australia between 2004 and 2005. There were no significant differences in biomass of litter in individual mounds between the two study plots. Seven components of litter were found in the mounds. The nutrient concentrations were higher in the woodland than in the shrubland plot, although the differences were not statistically tested, and the total amount of each nutrient measured was generally greater in the woodland than in the shrubland plot. The aforementioned results show that D. tamminensis harvests various plant material according to biomass availability. The role of this termite takes on particular importance in view of the fact that Western Australian soils are notoriously impoverished in nutrients.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.15 no.3
• /
• pp.80-89
• /
• 2007

Two endogenous endo-${\beta}$-1,4-D-glucanase (EGase, EC 3.2.1.4) cDNAs were cloned from the midgut of the earthworm Eisenia anderi, and named EaEG2 and EaEG3, respectively. A sequence of 1,368 bp was determined and the coding region is composed of 456 amino acid residues including the initiation methionine. The N-terminal region of 20 residues in the deduced sequence was regarded as the signal peptide. These EGases belong to glycosyl hydrolase family 9 (GHF9) and showed high levels of identity(51-55%) with selected termite, cockroache, crayfish and mollusc EGases. The EGases of earthworm consist of three consensus catalytic domains found in most microbial cellulases. A phylogenetic tree was constructed using the deduced amino acid sequence data matched through the BLASTX program and showed that GHF9 families could be divided into five groups of arthropoda, bacteria, plant, annelida and mollusc.

• Journal of the Korean Wood Science and Technology
• /
• v.49 no.5
• /
• pp.514-534
• /
• 2021

To estimate the territorial size of Reticulitermes speratus, a species of subterranean termites that damages wooden structures in Korea, appropriate dye markers were selected and the diffusion tendency was analyzed. According to the results of the sensitivity assessment using sawdust diet, increase in dye concentration reduced the amount of feed consumption but the dyeing becomes more intense. Except for the Neutral Red 0.5% group, all other concentration groups, including the control group, showed a survival rate of > 85% until week 4. For both, Nile Blue A and Neutral Red dye markers, all concentration conditions > 0.2%, except for the 0.1% concentration, were maintained for 11 weeks, and no sign of transfer effect was found except when the termites were fed with the dye markers. Therefore, it appears that 0.2% of Nile Blue A and Neutral Red is the optimal concentration for monitoring the R. speratus colonies. Additionally, we prepared an indoor 40 m long foraging arena consisting of a colony of 25,000 termites and released individuals stained with 0.2% of Nile Blue A and Neutral Red at both ends to assess the diffusion trends over time. The results showed that it took approximately 7 days for each dyed individual to gradually cover the 40 m distance and mix with each other. These findings reveal that when mark-release-recapture monitoring is conducted on the R. speratus colonies damaging wooden structures, the extent of the colony's activity area could be measured and different colonies could be distinguished from each other.

• Journal of Conservation Science
• /
• v.35 no.2
• /
• pp.177-186
• /
• 2019

A Termiticide that is applied to the soil treatment method, one of the methods for preventing termites in Korea's wooden cultural properties, will be subjected to the leaching of the effective ingredient in treated soil by the moisture behavior of rain. As a result, termiticide is deteriorated and needs to be reprocessed, but the standards and evaluation methods are nonexistent in korea. Accordingly, a basic indoor evaluation measure was proposed for the evaluation of the effectiveness of the termiticide chamber and the calculation of the reprocessing period. First, avoidance and contact toxicity were assessed at two concentrations of the same termiticide as a method for assessing termiticide suitability. The evaluation of mortality revealed that the soil termiticide used in this experiment was non-repellent, and that death from contact was confirmed. Afterwards, artificial rainfall and soil penetration tests were conducted to determine efficacy of termiticide in soil and the approximate reprocessing period was calculated by comparing the weather data. Persistence evaluation revealed perforation by termites after continuous water exposure of more than about 160 to 170mm of water injection condition. Based on the results, compared with weather data for the last five years, the termiticide of concentration used in this experiment is expected to remain effective for about one year if treated after September. The purpose of this study was to provide basic data for the establishment of a manual for the selection of termiticide for soil treatment by calculating the efficacy for termite mortality and the duration of the leaching effectiveness by water behavior in soil.

• Journal of Conservation Science
• /
• v.38 no.3
• /
• pp.180-191
• /
• 2022

Wooden cultural heritage are exposed to the external environment as they and there are many difficulties in conservation due to their location and size. Among them, biological damage caused by termites or mold consumes a lot of money and time. Select and use wood preservatives to prevent biological damage: Wood preservatives were selected and the worst environmental conditions, temperature 60±3℃, humidity 55±5%, and light intensity of 0.35 W/m², were subjected to aging treatment to analyze chemical changes. Through the deterioration process, it was confirmed that the change in color difference decreased in the wood preservative treatment compared to the Control group. As a result of measuring the content of the active ingredient contained in the deterioration process of the wood preservative, it was confirmed that the active ingredient content of Gori22 and Bondex Preserve III was higher than that of the comparative Wood Keeper A. Through experiments, the shelf life and treatment period can be predicted by measuring the extent to which wood preservatives affect the change of wood specimens during the deterioration process and the content of active ingredients. In conclusion, various wood preservatives were prepared, and the possibility of selectively selecting wood preservatives according to the environment, topography and period was presented as a major evaluation factor.