Heat-treated wood has good dimensional stability,durability,and color,but its susceptibility to fungal growth affects its commercial value.In this study,lumber harvested from mature Masson’s pine(Pinus massoniana Lam...Heat-treated wood has good dimensional stability,durability,and color,but its susceptibility to fungal growth affects its commercial value.In this study,lumber harvested from mature Masson’s pine(Pinus massoniana Lamb.)was vacuum impregnated with a basic copper salt solution(copper hydroxide,diethanolamine,and polyethylene glycol 200)prior to heat-treatment at 220℃ for 3 h.Antifungal properties,surface chemistry,crystal structure and sugar contents were tested,compared with heat treatment alone.The results showed that the samples treated by heating without copper salt treatment showed poor suppression of fungal growth,the copperimpregnated heat-treated wood suppressed(100%)the growth of Botryodiplodia theobromae Pat.,Aspergillus niger V.Tiegh.,Penicillium citrinum Thom,and Trichoderma viride Pers.The combined results of X-ray photoelectron spectroscopy,X-ray diffraction and sugars analysis suggested that fungal inhibition by the heat-treated copper-bearing Masson’s pine was mainly due to the reduction of the metal salt by PEG200 at high temperature to generate copper nanoparticles.In addition,the reduced sugar content of the treated timber,and hence the nutrient substrate for spoilage microbes,reduced in the presence of the metal salts at high-temperature.This study has demonstrated an effective method of increasing low-grade wood’s utility and commercial value.展开更多
In this study,we monitored for the impact of three aqueous extracts of plants(Azadirachta indica,Hyptis suaveolens and Solanum lycopersicum)on insect pests abundance in okra(Abelmoschus esculentus L.)crop,compared to ...In this study,we monitored for the impact of three aqueous extracts of plants(Azadirachta indica,Hyptis suaveolens and Solanum lycopersicum)on insect pests abundance in okra(Abelmoschus esculentus L.)crop,compared to a synthetic chemical«SAUVEUR 62 EC»,having as active ingredients,acetamiprid 32g/l and Lambda-cyhalothrin 30g/l.Foliar applications by these extracts were done using manual sprayers.After treatment,the insects were caught using two methods(pitfall traps and colored bowls traps).A total of 6505 insects belonging to nine orders were recorded in four plots.The plot 1(9 orders)was the most diverse,followed by the plot 3(8 orders),the plot 2 and 4(7 orders respectively).Coleoptera,Lepidoptera,Diptera,Orthoptera and Hemiptera were the most frequents.The chemical treatment has impacted significantly the number of orders(p<0.05)but,the insect abundance was impacted significantly by the different biological treatments(p<0.05).This study showed that the aqueous extract of Solanum lycopercicum was more effective on the abundance of pests belonging to Hemiptera,while the aqueous extracts of Azadirachta indica and Hyptis suaveolens were effectives on the abundance of pests belonging to Coleoptera.The chemical treatment was effective on the pests belonging to both orders.展开更多
基金This research was sponsored by the Guangdong Forestry Science and Technology Innovation Project“Research on the Thermal Modification of Eucalyptus and Spingbract Chinkapin Wood and the Key Technologies of Their Wood Flooring Preparation”(No.2018KJCX006).
文摘Heat-treated wood has good dimensional stability,durability,and color,but its susceptibility to fungal growth affects its commercial value.In this study,lumber harvested from mature Masson’s pine(Pinus massoniana Lamb.)was vacuum impregnated with a basic copper salt solution(copper hydroxide,diethanolamine,and polyethylene glycol 200)prior to heat-treatment at 220℃ for 3 h.Antifungal properties,surface chemistry,crystal structure and sugar contents were tested,compared with heat treatment alone.The results showed that the samples treated by heating without copper salt treatment showed poor suppression of fungal growth,the copperimpregnated heat-treated wood suppressed(100%)the growth of Botryodiplodia theobromae Pat.,Aspergillus niger V.Tiegh.,Penicillium citrinum Thom,and Trichoderma viride Pers.The combined results of X-ray photoelectron spectroscopy,X-ray diffraction and sugars analysis suggested that fungal inhibition by the heat-treated copper-bearing Masson’s pine was mainly due to the reduction of the metal salt by PEG200 at high temperature to generate copper nanoparticles.In addition,the reduced sugar content of the treated timber,and hence the nutrient substrate for spoilage microbes,reduced in the presence of the metal salts at high-temperature.This study has demonstrated an effective method of increasing low-grade wood’s utility and commercial value.
文摘In this study,we monitored for the impact of three aqueous extracts of plants(Azadirachta indica,Hyptis suaveolens and Solanum lycopersicum)on insect pests abundance in okra(Abelmoschus esculentus L.)crop,compared to a synthetic chemical«SAUVEUR 62 EC»,having as active ingredients,acetamiprid 32g/l and Lambda-cyhalothrin 30g/l.Foliar applications by these extracts were done using manual sprayers.After treatment,the insects were caught using two methods(pitfall traps and colored bowls traps).A total of 6505 insects belonging to nine orders were recorded in four plots.The plot 1(9 orders)was the most diverse,followed by the plot 3(8 orders),the plot 2 and 4(7 orders respectively).Coleoptera,Lepidoptera,Diptera,Orthoptera and Hemiptera were the most frequents.The chemical treatment has impacted significantly the number of orders(p<0.05)but,the insect abundance was impacted significantly by the different biological treatments(p<0.05).This study showed that the aqueous extract of Solanum lycopercicum was more effective on the abundance of pests belonging to Hemiptera,while the aqueous extracts of Azadirachta indica and Hyptis suaveolens were effectives on the abundance of pests belonging to Coleoptera.The chemical treatment was effective on the pests belonging to both orders.
