Jenoh Elisha Mrabu, Traoré Mohamed, Kosore Charles, Koedam Nico
Kenya Marine and Fisheries Research Institute (KMFRI), Mombasa, Kenya.
Laboratory of Plant Biology and Nature Management (APNA), Ecology & Biodiversity, Vrije Universiteit Brussel, Brussels, Belgium.
PLoS One. 2021 Nov 2;16(11):e0259261. doi: 10.1371/journal.pone.0259261. eCollection 2021.
Infestation by a moth woodborer species is causing mortality of Sonneratia alba Sm. mangrove by tunneling through the inner bark, cambium and conductive tissue. Infestation leads to death of some infested branches, whereas in other cases infested branches have been observed to recover from infestation. We have used Fourier transform infrared spectroscopy (FTIR) to investigate the differences in macromolecule (polysaccharide and lignin) content present in branches that died (D) of the infestation, those that recovered (R) from the infestation and control branches (C) that were not subject to any infestation. Wood samples were taken from four sampling plots (A, B, C and D) in Gazi Bay (Kenya). From each of the four plots, 15 S. alba branches were taken from five trees, from which 1 cm thick discs were cut from each of these branches to be used as samples. To identify the most characteristic FTIR bands for the three groups of samples, Principal Component Analysis (PCA) was applied on the transposed data matrix. Furthermore, canonical discriminant analysis was applied on the data considering the main FTIR band that would be identified through the PCA factors. Finally, One-way ANOVA and post hoc test were used to verify the significance of the observed trends. Branches that recovered from infestation had higher relative abundance of lignified cells. We conclude that insect-infested S. alba undergo changes related to the lignocellulosic contents. The infestation induces a decrease of the proportion of the polysaccharide content and an increase of the proportion of the lignin contents.
一种蛾类蛀木虫的侵害正导致白骨壤红树林死亡，其通过蛀穿内皮、形成层和传导组织来实现。这种侵害会导致一些受侵害树枝死亡，而在其他情况下，观察到受侵害树枝能够从侵害中恢复。我们使用傅里叶变换红外光谱（FTIR）来研究在因侵害而死亡的树枝（D）、从侵害中恢复的树枝（R）以及未遭受任何侵害的对照树枝（C）中存在的大分子（多糖和木质素）含量的差异。木材样本取自肯尼亚加齐湾的四个采样区（A、B、C和D）。从这四个采样区中的每一个，从五棵树上选取15根白骨壤树枝，从这些树枝上各切下1厘米厚的圆盘作为样本。为了确定三组样本最具特征的FTIR波段，对转置的数据矩阵应用主成分分析（PCA）。此外，考虑到将通过PCA因子确定的主要FTIR波段，对数据应用典型判别分析。最后，使用单因素方差分析和事后检验来验证观察到的趋势的显著性。从侵害中恢复的树枝木质化细胞的相对丰度更高。我们得出结论，受昆虫侵害的白骨壤会发生与木质纤维素含量相关的变化。这种侵害导致多糖含量比例下降，木质素含量比例上升。
