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Borer fauna of Iran biodeterioration of wooden boats in Persian Gulf and Sea of Oman
1997 - IRG/WP 97-10230
In Persian Gulf and Sea of Oman (Indian Ocean) there are thousands of wooden boats from the time of Acheamenian and Sassand dynasti when India was a part of the Persian Empire. Now after 2500 years again, the Indian timbers specially Tectona Grandis and other Indian timbers and also tropical woods of Zanzibar (Tanzania) are brought to the Persian Gulf and Sea of Oman (Indian Ocean). Unfortunately the woods are not pressure impregnated but the boats are made from many kinds of woods (indigenous and exotic) and with bad oil impregnation (local impregnation). As a result the wooden boats are very badly attacked by different borers. None of the timber species currently in demand for boat building possesses any natural bioresistance, and will be completely destroyed within 6 to 12 months. The Iranian ministry of Jihad (reconstruction) should use pressure impregnation of wood with preservative chemicals, but the impregnation is inadequate. The need for long-term research in the field of marine biodeterioration for improving the efficiency of currently known control measures, with emphasis of application of non-polluting biological methods has been suggested in this paper.
P Niloufari


Biocidal property of the phenolic fraction of ethanol extractives of Hopea parviflora heartwood
1993 - IRG/WP 93-30003
Natural resistance of some species of timber to fungal decay and insect damage (particularly termite) is ascribed toxic nature and quantity of certain chemical substances present in the cell wall of heartwood. These chemical substances generally known to be Phenolic and Polyphenolic compounds (Rao 1982). Earlier investigations on extractives were mainly in relation to resistance of timber to decay and studies that induce resistance to termite attack had not received enough attention. Treated wood with phenolic fraction of ethanol extractives of Hopea parviflora heartwood have shown inuced resistance against decay fungi and termites, indicating these chemical substances are having biocidal properties. The observation warrant detailed chemical studies of the extractives for their utilisation of wood protective substance.
R V Krishnan, K S Theagarajan, H S Ananthapadmanabha, M Nagaraja Sharma, V V Prabhu, H C Nagaveni


Dip-diffusion of dressed timber - Effect of drying
1989 - IRG/WP 3509
The effect of drying on dip-diffused dressed freshly sawn timber was determined by the depth of penetration of boron achieved on the two test timber species, White cheesewood (Alstonia scholaris) and Light Hopea (Hopea papuana). The results obtained showed that light density White cheesewood was completely penetrated even after 3 days drying while Light hopea, treated immediately achieved 5.2 mm penetration after 2 days diffusion and subsequently better after 14 and 21 days diffusion. Adequate penetration was only achieved after 14 and 21 days diffusion when there was delay between 30 minutes and 72 hours.
H C Konabe


Dip-diffusion of dressed timber - Effect of drying
1990 - IRG/WP 3603
The effect of drying on BFCA dip-diffused, dressed, freshly sawn timber was determined by the depth of penetration of boron achieved on two test timber species, White Cheesewood (Alstonia scholaris) and Light Hopea (Hopea papuana). The results obtained showed that the light density White cheesewood was completely penetrated even after 3 days drying while Light Hopea, treated immediately achieved 5.2 mm penetration after 2 days diffusion and subsequently better after 14 and 21 days diffusion. Adequate penetration was only achieved after 14 and 21 days diffusion when there was delay between 30 minutes and 72 hours.
H C Konabe


Evaluation of tropical wood by-products as a potential source for termite control products
2001 - IRG/WP 01-10408
Termites damaging in houses represent an ever growing threat in Europe, where the phenomenon has accelerated during the last ten years, as well as in the tropics, where infestations are permanent. To fight against this plague, the current methods used, through injection of organochloric or organophosphorized products into the timber structures and walls, are belonging to the past due to the toxicity and harmful consequences of their use on the environment. New techniques were developed and research organisations are still working on minimizing the environmental impacts through the elaboration of new products. Some tropical wood species from French overseas territories (mainly French Guyana), like Ocotea rubra, Licaria canella and Aniba parviflora (Lauraceae), contain repellent, antifeeding or toxic substances which might be extracted to obtain molecules to be used for new wood preservatives. CNRS and CIRAD-ForĂȘt are currently elaborating techniques that will allow to discriminate the possible effects of various molecules contained in sawdusts as regards to termites. Both termite species, Heterotermes indicola and Reticulitermes santonensis, have shown different behaviours depending on the wood species. These wood species were consequently classified according to their repulsive, antifeeding or toxic effects against both termite species studied. Considering the results obtained, it would then be worthwhile to use wood wastes from sawmills. Being so, the up-grading of by-products can be the basis for formulations of new wood preservatives with low environmental impacts and still providing durability against termites to wood species with a low natural durability.
A Zaremski, S Robert, J-L Clement, D Fouquet