木材天然耐腐性研究评介

<正>不同树种的木材对微生物分解的天然抵抗力是不同的,同一树种的不同个体的耐腐力亦有很大的不同,甚至同一棵树的不同部位其耐腐性也会有变化,特别是对于那些具有很耐腐心材的树种。在耐腐树种中,其耐腐力从心材的外缘到髓芯逐渐降低。在心材形成过程中积聚起来的毒性提取物是耐腐力的主要来源。已知对腐朽有抑制作用的大多数心材提取物是酚类化合物。香芹酚、(艹守)侧素、栎精,3,5-二羟苯乙烯和单宁都可能对耐腐性起作用。本文还论述了木材耐腐性的其它一些因素,例如木材细胞壁的木质化,纤维素的结晶度,贮存食物的枯竭,木材水份的含量以及木材结构对白腐菌和褐腐菌的不同抵抗力等。

A REVIEW OF STUDIES ON NATURAL RESISTANCE OF WOOD TO MICROBIAL DETERIORATION

Natural resistance of wood from differnt tree species to microbial deterioration differs considerably. Individual trees of the same species may also vary a great deal in decay resistance. Natural durability varies within the same tree too, especially in species with very durable heartwood. In the durable species, decay resistance decreases incessantly from the outer heartwood to the pith. Toxic extractive substances deposited during the formation of the heartwood are the principal source of decay resistance. Most of the heartwood extractives known to inhibit decay are phenols. Carvacrol, 2-thujaplicin, quercetin pinosyluin, and tannins all seem to contribute to decay resistance, other mechanisms of natural durability of wood, such as the lignification of wood cell walls, crystallinity of the cellulose, depletion of reserve food materials, higher moisture rcquirments for wood-inhabiting fungi, and different resistance of the wood structure to white-rot and brown-rot fungi arc also discussed, in this paper.