Lindroth Richard L, Bloomer Mark S
Department of Entomology and Environmental Toxicology Center, University of Wisconsin, 1630 Linden Drive, 53706, Madison, WI, USA.
Oecologia. 1991 May;86(3):408-413. doi: 10.1007/BF00317609.
Interactions between quaking aspen (Populus tremuloides) and the forest tent caterpillar (Malacosoma disstria) are likely to be influenced by leaf protein and phenolic glycoside levels, and insect detoxication activity. We investigated the direct and interactive effects of dietary protein and phenolic glycosides on larval performance and midgut enzyme activity of forest tent caterpillars. We conducted bioassays with six artificial diets, using both first and fourth stadium larvae. Four of the diets comprised a 2×2 factorial design-two levels of protein, each with and without phenolic glycosides. Additionally, we assayed high protein diets containing S,S,S-tributylphosphorotrithioate (DEF, an esterase inhibitor) and DEF plus phenolic glycosides. Enzyme solutions were prepared from midguts of sixth instars and assayed for β-glucosidase, esterase and glutathione transferase activities. First instar mortality and development times were higher for larvae on diets low in protein or containing phenolic glycosides. Effects of phenolic glycosides were especially pronounced at low protein levels and when administered with DEF. Fourth instar development times were prolonged, and growth rates reduced, in response to consumption of low protein diets. Effects of phenolic glycosides on growth were less pronounced, although the effect for larvae on the low protein diet was nearly significant. Activity of each of the enzyme systems was reduced in larvae reared on low protein diets, and esterase activity was induced in larvae fed phenolic glycosides. Our results suggest that larval performance may be strongly affected by levels of protein and phenolic glycosides commonly occurring in aspen foliage, and that these factors may play a role in differential defoliation of aspen by forest tent caterpillars.
颤杨（Populus tremuloides）与森林天幕毛虫（Malacosoma disstria）之间的相互作用可能会受到叶片蛋白质和酚糖苷水平以及昆虫解毒活性的影响。我们研究了膳食蛋白质和酚糖苷对森林天幕毛虫幼虫性能和中肠酶活性的直接和交互作用。我们使用一龄和四龄幼虫，用六种人工饲料进行了生物测定。其中四种饲料采用2×2析因设计——两种蛋白质水平，每种水平分别添加和不添加酚糖苷。此外，我们测定了含有S,S,S-三丁基硫代磷酸酯（DEF，一种酯酶抑制剂）和DEF加酚糖苷的高蛋白饲料。酶溶液由六龄幼虫的中肠制备，并测定β-葡萄糖苷酶、酯酶和谷胱甘肽转移酶活性。蛋白质含量低或含有酚糖苷的饲料喂养的幼虫，一龄幼虫的死亡率和发育时间更高。酚糖苷的影响在低蛋白水平以及与DEF一起使用时尤为明显。四龄幼虫食用低蛋白饲料后，发育时间延长，生长速率降低。酚糖苷对生长的影响不太明显，尽管低蛋白饲料喂养的幼虫的影响几乎显著。在低蛋白饲料中饲养的幼虫，每种酶系统的活性都降低，而喂食酚糖苷的幼虫酯酶活性被诱导。我们的结果表明，幼虫性能可能会受到颤杨叶中常见的蛋白质和酚糖苷水平的强烈影响，并且这些因素可能在森林天幕毛虫对颤杨的不同落叶情况中起作用。
