Microwave treatment against the attack of wood boring in timber structures

H. Mõlder¹,*, J. Järvik¹, K. Pilt², M. Märss¹ and R. Reiska³

¹Department of Electrical Engineering, Tallinn University of Technology,Ehitajate tee 5, 19086 Tallinn, Estonia, *Correspondence: heigo.molder@ttu.ee
²Estonian Mycology Research Centre, Heina 7, 50604 Tartu, Estonia
³Department of Polymer Materials, Tallinn University of Technology, Ehitajatetee 5, 19086 Tallinn, Estonia

Abstract:

Timber is a sustainable building material that can be damaged by several biologicalagents, like insect activity, fungal decay and more. This is one of the most common problems inhistorical buildings. This paper gives an overview of microwave (MW) technologies, whichhave been used in wood boring insect control. Electromagnetic waves penetrate throughout theentire volume of treated material, causing water in wood and wood boring insects infestingwood to heat up simultaneously. The rise of temperature is the main effect used in MW pestcontrol. A microwave wood boring insect neutralisation device herein is introduced. This paperlooks at the long-distance microwave irradiation and radiation energy distribution of theirradiated surface. Tests for evaluation of wood pest elimination by MW radiation are specifiedand discussed.

Key words:

Flea beetle (Coleoptera: Chrysomelidae) response to alkyl thiocyanates and alkyl isothiocyanates

I. Liblikas¹⋅², E. Mõttus¹, A.-K. Borg-Karlson², S. Kuusik¹, A. Ojarand¹, A. Kännaste¹ and J. Tanilsoo¹

¹Estonian Agricultural University, Kreutzwaldi 1, 51014 Tartu, Estonia
²The Royal Institute of Technology, Sweden, Dept of Chemistry, Organic Chemistry, Ecological Chemistry, KTH, S-100 44 Stockholm, Sweden

Abstract:

The attractivity of nine compounds, allyl isothiocyanate (allyl IT), benzyl isothiocyanate (benzyl ITC), 3-butenyl isothiocyanate (butenyl ITC), 3-butenyl thiocyanate (butenyl TC), butyl isothiocyanate (butyl ITC), butyl thiocyanate (butyl TC), 2-phenylethan-1-yl isothiocyanate (phenetyl ITC), 2-phenyleth-1-yl thiocyanate (phenetyl TC), and 2-phenylethan-1-ol, was compared to the beetle genera Phyllotreta species. Field tests were performed on fields of wild crucifer plants and on the edge of an oilseed rape field. Test places were at Juuru in Northern Estonia, at Valgeristi in the middle of Estonia and at Matsi in Southern Estonia. In our tests, Phyllotreta spp were most attracted to butenyl TC and butenyl ITC; allyl ITC and other tested alkyl-TC, alkyl-ITC, aryl-TC and aryl-ITC had lower attractivity. Cylindrical traps with a large clued area were tested and are recommended for practical usage, capillary polyethylene dispensers are recommended instead of sachet type dispensers. Emission of substances from sachet dispensers is described in the article.

Key words:

2-phenyl-1ethyl thiocyanate, 3-buten-1-yl isothiocyanate, 3-buten-1-yl thiocyanate, flea beetles, kairomone, pest control, Phyllotreta spp., sachet dispenser