The consequences of leaf damage for subsequent insect grazing on birch (Betula spp.)
The consequences of leaf damage for subsequent insect grazing on birch (Betula spp.)
复制标题
叶子受损对桦树（桦树属）随后昆虫放牧的影响
作者：
B. E. Silkstone
摘要1985年初夏，对短毛Betla pubescens和B. pendula的叶片进行了较低程度的人为破坏。使用了16棵树，损害以两种方式分布在整个树冠上。它要么随机分布在树上，要么被限制在树冠的局部区域。每棵树最多有250片叶子受损，并酌情标记出对照叶子的位置。夏末采集实验叶和对照叶进行分析。自然发生的食草动物随后的放牧模式受到先前对树叶的损害的影响。较少人为损坏的叶片随后受到昆虫放牧的损害。先前受损叶片的虫害频率分布与对照叶片有显著差异，且后续遭受虫害的实验叶片被虫害的组织较少。研究结果表明，在田间，短毛短毛杨和小摆毛杨的叶片适口性确实发生了损伤引起的变化，其主要作用是将损伤分散到整个冠层。
SummaryLow levels of artificial damage were imposed on the leaves of Betla pubescens and B. pendula in early summer 1985. Sixteen tress were used and the damage was distributed throughout the canopy in two ways. It was either randomly dispersed on the tree, or restricted to a localised region of the canopy. Up to 250 leaves/tree were damaged and the position of control leaves was marked as appropriate. At the end of the summer the experimental and control leaves were collected for analysis. Subsequent patterns of grazing by naturally-occurring herbivores were affected by the previous damage to the foliage. Fewer artificially-damaged leaves received subsequent insect grazing damage. The frequecy distribution of insect damage to previously-damaged leaves was significantly different from that of the control leaves, and less leaf tissue was removed from those experimental leaves which did receive subsequent insect attack. The evidence presented suggests that wound-induced changes in leaf palatability do occur in B. pubescens and B. pendula in the field and that a major role is to disperse the damage throughout the canopy.