毛竹和重组竹腐朽前后的表面颜色及耐腐性能

以毛竹和重组竹为研究对象,用绵腐卧孔菌(PV)、密粘褶菌(GT)两种褐腐菌和彩绒革盖菌(CV)、变色栓菌(TV)两种白腐菌进行腐朽试验,比较分析了毛竹和重组竹腐朽前后表面视觉性质及其质量损失差异。结果发现:毛竹和重组竹颜色均发生了显著变化,主要表现为明度(L~*)降低,色度值(C)、红绿轴色品指数(a~*)和黄蓝轴色品指数(b~*)显著增大,其中绵腐卧孔菌对毛竹及重组竹的色差影响最大。重组竹(耐绵腐卧孔菌)能达到Ⅰ级强耐腐水平;毛竹(耐绵腐卧孔菌)和重组竹(耐密粘褶菌和彩绒革盖菌)达到了Ⅱ级耐腐水平;毛竹(耐密粘褶菌、彩绒革盖菌和变色栓菌)和重组竹(耐彩绒革盖菌)为Ⅲ级稍耐腐水平。整体来看,重组竹对白腐菌和褐腐菌的耐腐效果好于毛竹。绵腐卧孔菌虽然对毛竹和重组竹的降解能力最弱,但对其颜色变化的影响却最大。扫描电镜可观察到彩绒革盖菌通过毛竹导管壁上的纹孔进入薄壁细胞、伴胞等,同时通过分泌木质素酶导致其细胞壁降解。

Assessment of the surface color properties and decay resistance performance of moso bamboo and bamboo scrimber before and after fungal decay

The mildew and decay of bamboo are long-term problems associated with bamboo processing and utilization.In this study,we examined the effects of the wood rot fungi Poria vaporaria,Gloeophyllum trabeum,Coriolus versicolor,and Trametes versicolor on the visual properties and quality of moso bamboo(Phyllostachytes edulis)and bamboo scrimber.The results revealed significant changes in the color of infected moso bamboo and bamboo scrimber,which were primarily manifested as reductions in brightness,as well as significant increases in chromatic value C,red-green axis color index a~*,and yellow-blue axis color index b~*,with Poria vaporaria being found to have the most pronounced effects on differences in the color of the two materials.Bamboo scrimber(infected by Poria vaporaria)was found to reach a gradeⅠlevel of strong decay resistance;bamboo(infected with Poria vaporaria)and bamboo scrimber(infected by G.trabeum and C.versicolor)showed a gradeⅡlevel of decay resistance;and bamboo(infected by G.trabeum,C.versicolor,and T.versicolor)and bamboo scrimber(infected by C.versicolor)showed a gradeⅢlevel of slight decay resistance.Generally,bamboo scrimber was found to be characterized by a decay resistance superior to that of moso bamboo.Among the assessed fungi,the degradation ability of Poria vaporaria on moso bamboo and bamboo scrimber was found to be the weakest,although this fungus has the most pronounced influence on color change.Scanning electron microscopy analysis revealed that following a white-rot assessment,the hyphae of the C.versicolor enter bamboo vessels and subsequently penetrate the parenchyma cells via pits in the vessel walls,and that during the invasive process,this fungus secretes ligninases that disrupt cell wall structure.The findings of this study will lay a foundation for further studies examining the chemical mechanisms whereby wood rot fungi affect the color and decay resistance of bamboo and bamboo scrimber.