Neuvonen S, Haukioja E
Laboratory of Ecological Zoology, Department of Biology, University of Turku, SF-20500, Turku 50, Finland.
Oecologia. 1984 Jul;63(1):71-74. doi: 10.1007/BF00379787.
The effects of artificial defoliation of birch trees in the previous year on the consumption and utilization of food by a geometrid larva, Epirrita autumnata, were studied in laboratory. The leaves were collected from two sites on a slope of a fell. Defoliation had a significant retarding effect on approximate digestibility, efficiency of conversion of ingested food, relative consumption rate and relative growth rate but not on efficiency of conversion of digested food. The effects were to the same direction with leaves from the two sites, but the response was stronger with leaves from the zone defoliated by Epirrita during mid-sixties. The defensive nature of the response(s) of birch to defoliation is discussed in the light of these results. It is concluded that contrary to the hypothesis of Moran and Hamilton (1980) no increase in the consumption incurred by individual trees could be shown in this system.
在前一年对桦树进行人工落叶处理后，研究了其对尺蛾幼虫Epirrita autumnata食物消耗和利用的影响，实验在实验室中进行。树叶采自一座山上斜坡的两个地点。落叶对近似消化率、摄入食物转化率、相对消耗率和相对生长率有显著的抑制作用，但对消化食物转化率没有影响。来自两个地点的树叶产生的影响方向相同，但与六十年代中期被Epirrita落叶的区域的树叶相比，反应更强。根据这些结果讨论了桦树对落叶反应的防御性质。得出的结论是，与Moran和Hamilton（1980）的假设相反，在这个系统中未发现单株树木的消耗量增加。
