MICROSCOPIC STUDIES ON MODIFIED WALL STRUCTURE AND LIGNIN TOPOCHEMISTRY IN XYLEM FIBRES OF POPLAR AFTER WOUNDING
MICROSCOPIC STUDIES ON MODIFIED WALL STRUCTURE AND LIGNIN TOPOCHEMISTRY IN XYLEM FIBRES OF POPLAR AFTER WOUNDING
复制标题
损伤后杨木木质部纤维改性壁结构及木质素拓扑化学的微观研究
DOI：
10.4067/s0718-221x2006000200003
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发表时间：
2006
期刊：
影响因子：
--
通讯作者：
U. Schmitt
中科院分区：
文献类型：
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作者：
C. Frankenstein;U. Schmitt
关于损伤后分化木质部组织的精细结构的信息仍然很少。这项研究提供了关于细胞壁修饰的信息，特别是木质素在伤害时分化的杨树木质部纤维中的分布。样本采集自受伤的杨树种。树木经过长达23个月的响应期后，进行显微分析。用光学显微镜和透射电子显微镜对伤侧木质部纤维的壁结构进行了一般研究，而用紫外-显微分光光度法研究了这些细胞的木质素分布模式。木质部纤维靠近伤口以及位于伤前分化的木质部和伤后的组织之间的过渡区，形成了明显厚于正常纤维的次生壁。这些木质素含量也略高于正常水平，且木质素在中叶和次生壁中分布不均。杨树受伤害后，木质部纤维中的木质素拓扑化学成分和木质部纤维中木质素的结构发生变化。据推测，这种伤口反应是分区过程的一部分，因此有助于增加抵抗力。
Information about fine structure following wounding in differentiating xylem tissue is still scarce. This study provides information on cell wall modifications with special emphasis on lignin distribution in xylem fibres of poplar differentiating at the time of wounding. Samples were collected from wounded Populus spp. trees after response periods of up to twenty-three months and processed for microscopic analyses. General studies on the wall structure of wound-adjacent xylem fibres were carried out with light and transmission electron microscopy, whereas lignin distribution patterns of these cells were examined by UV-microspectrophotometry.Xylem fibres close to the wound and within a transition zone between differentiated xylem laid down prior to and tissue laid down after wounding developed a distinctively thicker secondary wall than normal fibres. These modified walls also showed a slightly higher lignin content, than normal and a heterogeneous lignin distribution in the middle lamella and the secondary wall.Wounding in poplar induces a modified wall structure and lignin topochemistry in xylem fibres differentiating at the time of wounding. It is assumed that this wound response is part of the compartmentalization process and therefore contributes to an increased resistance.