Effect of seed methanol extracts from Prosopisafricana, Pentaclethramacrophlla and Erythrophleumsuaveolens on termites infestation of some common wood species

Abstract

The aim of this study was to investigate termicidal properties of seeds of three tropical trees species. Methanol extracts of P. africana, P. macrophylla, and of E. suaveolens seeds were prepared and applied on three common wood species viz: FicussppDaniella oliveri and Vitellariaparadoxa.The treated wood sample was buried to a depth of 10 cm for graveyard experiment for a period of 5 months. Spacing was 3 m between holes and 3 m between replicates. Result on percentage extract retention indicated that E. suaveolens extract displayed varying absorption percentages across wood species, with differences observed in D. oliveri and V. paradoxa woods treated with Solignum compared to extracts. Higher extract concentrations correlated with increased absorption. V. paradoxahad the highest mean percentage absorption (31.50%) and retention (31.50%) and was recorded for Solignum. Solignum. treatment wood showed comparatively lower (8.02% - 14.22%), weight loss percentages suggesting potential efficacy in mitigating termite-induced damage. Untreated wood samples exhibited significantly higher (46.07% - 58.65%) weight loss percentages, indicating vulnerability to termite infestation. Highest Concentration (1.5 g) of E.suaveolens seed methanol extract had moderately low weight of 15.14% ± 9.87% (D. oliveri), 19.36% ± 11.98% (V. paradoxa), and 20.19% ± 7.04% (Ficus spp.). Also, 1.5 g concentration of P.macrophylla seed methanol extract had modest weight loss of 12.60% ± 6.78% for D. oliveri; 21.00% ± 12.87% for V. paradoxa and 21.56% ± 16.40% for Ficus spp. In conclusion, 1.5 g concentration of seed methanol extract was relatively the most active and it is recommended for wood treatment against termites.The most susceptible wood species to termite attack was Ficusspp and it should be properly treated before employed in service.