Abstract Defoliating insects damage forest plantations, but the estimation of their losses does not take into account wood quality changes. The objective was to evaluate the wood quality and pulp production of two clones of Eucalyptus grandis × Eucalyptus urophylla (clone A) and Eucalyptus saligna (clone B) damaged or not by defoliating insects. Five healthy trees and five attacked by Gonipterus platensis Marelli (Coleoptera: Curculionidae) were selected per clone. The wood volume per hectare in the affected settlements was at least 9% lower and damaged trees showed lower wood basic density, with at least 4.6%. The lignin and extractive content in the wood increased by at least 5.6 and 45%, respectively, while the syringyl/guaiacyl (S/G) ratio remained constant for clone A and increased 10% for clone B. For pulps, an increased effective alkali and decreased pulp yield were experienced for both clones while bleaching or pulp quality was not affected. In the stands affected by defoliating insects, productivity was 9 and 19% lower considering the wood volume per hectare and 15 and 24% considering the cellulose pulp production per hectare, respectively.

中文翻译：

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昆虫落叶会降低木材质量和纤维素纸浆产量

摘要 落叶昆虫会破坏人工林，但对其损失的估计并未考虑木材质量的变化。目的是评估大桉×尾叶桉两个克隆（克隆 A）和桉树（克隆 B）的木材质量和纸浆产量，它们被落叶昆虫破坏与否。每个克隆选择五株健康树木和五株被 Gonipterus platensis Marelli（鞘翅目：仙茅科）攻击的树木。受影响定居点的每公顷木材量至少降低了 9%，受损树木的木材基本密度更低，至少为 4.6%。木材中的木质素和提取物含量分别增加了至少 5.6% 和 45%，而克隆 A 的丁香基/愈创木酰基 (S/G) 比率保持不变，克隆 B 增加了 10%。对于纸浆，两种克隆的有效碱增加和纸浆产量降低，而漂白或纸浆质量不受影响。在受落叶昆虫影响的林分中，考虑到每公顷木材量，生产率分别降低了 9% 和 19%，考虑到每公顷纤维素纸浆产量，生产率分别降低了 15% 和 24%。