采用扫描电镜技术(SEM)观察研究各种不同真菌败坏竹材的宏观和微观变化.结果表明:霉菌的菌丝和孢子团仅聚集在竹材表面,不能进入竹材内部,不会破坏竹材的内部结构或影响内部颜色变化；变色菌不仅在竹材的表面聚集,还深入到竹材内部使其内外都发生青色、褐色或黑色等颜色变化,但对竹材的质量没有大的影响；腐朽菌不仅侵入竹材内部,还造成竹材明显质量损失.变色菌和腐朽菌侵入竹材的过程为:菌丝由外部细胞壁纹孔侵入竹材内部,沿着后生木质部导管、原生木质部和薄壁组织细胞壁之间的孔隙蔓延,填充到竹材的维管束中.腐朽菌密粘褶菌降解竹材的过程为:穿过细胞壁的菌丝在周围的胞壁上形成孔洞,孔洞逐步扩展,各孔洞连成片,最终导致组织的破损和崩解.竹材组织受褐腐菌侵染发生降解的顺序是:先是木质部导管细胞壁,而后基本薄壁组织细胞壁,最后是纤维.%Mould, stain and decay fungi are the common microorganisms that can damage bamboo. Scanning electron microscope ( SEM) was used in this study to investigate the macro- and micro-structural changes in bamboo after attack by these three types of fungi. The results showed that the mycelia of the mould and stain fungi were found only on the surfaces of the bamboo specimens and no hyphae were detected inside. The hyphae of the stain fungi were found to penetrate into bamboo and grew in metaxylem vessels, and then expand through the pits between cells; the stain fungi caused blue, brown and black discolorations from deep inside of the bamboo specimens. Similar to the stain fungi, the hyphae of the brown-rot fungus was also found to intrude from cell to cell through pits between cells; moreover, they gradually became denser and thicker causing very visible boreholes in the cell walls which then led to large-area cell wall rupture and collapse. It was observed from the vertical sections of the bamboo specimens under SEM that the brown-rot fungus firstly attacked the cell walls of the metaxylem vessels, followed by the parenchyma cells, and finally the fiber cells in bamboo.
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