Termite castes (soldiers, nymphs, and reproductives) are unable to feed themselves and are fed via trophallaxis from the workers which degrade the cellulose from wood. It is of great economical importance to ascertain the efficacy of preservatives against wood decay organisms in order to extend wood products service life. Remedial chemical product applications are used primarily as wood treatments to protect timber from colonization by subterranean termites. However, due to environmental and health sanitary pressure, it is imperative to find environmentally friendly alternative to synthetic chemical formulations. The insecticide efficacy of Groupe Berkem new generation of polyphenol-containing formulations was investigated against the deterioration of Scots pine (Pinus sylvestris) sapwood by two subterranean termite species and by a house long-horned beetle. The efficacy of our phenol-extract formulations was investigated against two termite species Coptotermes gestroi and Prorhinotermes canalifrons and Reticulitermes flavipes of the Rhinotermitidae family. For the three species, two types of plant polyphenol formulations were assayed on Scots pine specimens for their anti-termite activity according to the NF EN 117 procedure. After 1 to 3 months of exposure to the termites, all the treated specimens showed a total protection against both termite species, with 100% mortality. No surviving termite individuals could be observed compared to 48 to 52% mortality in the untreated controls. The effectiveness of polyphenols was higher against P. canalifrons. With R. santonensis, lethal concentration of the formulations was obtained at 11% (w/w) and retention of product in wood of about 60 kg/m3 with no surviving populations among workers, soldiers and nymphs. The activity of our polyphenol formulations against the European house longhorn beetle Hylotrupes bajulus (L.) was also tested on specimens of P. sylvestris wood. The toxic value of the preservative formulation was determined on recently hatched larvae according to NF EN 47. Dried Scots pine wood specimens were impregnated by low-pressure vacuum with our polyphenol formulation at various concentrations over a period of more than 24 weeks. The mortality of larvae surviving the treatment was determined at various times (4, 12 and 24 weeks, respectively) and the lethal concentration ascertained. The formulation was efficient at concentration as low as 3.1% (w/w) and retention of 16 kg/m3. Similar results by surface application were obtained according to NF EN 1390 (remedial treatment). The present results show that the incorporation of plant polyphenol extracts in our biological eco-friendly insecticide formulations was an effective alternative for the control of termite populations as well of woodboring beetles. Polyphenols have a strong potentiality for the protection of construction wood against xylophagous organisms. Our natural plant extracted new generation of biocides meet the requirements of governmental directives.

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