Department of Entomology, Michigan State University, 48824, East Lansing, Michigan.
J Chem Ecol. 1992 Sep;18(9):1661-71. doi: 10.1007/BF00993237.
The role of toxins and deterrents in preventingtroilus group species (Lepidoptera, Papilionidae) from feeding on magnoliaceous hosts was investigated using bioassay-directed isolation ofMagnolia virginiana allelochemicals. A fraction consisting of three neolignan compounds significantly reduced survival of first instarP. palamedes, atroilus group member. Two of these compounds, magnolol and a biphenyl ether, were tested individually and were both toxic toP. palamedes. The larval survival ofP. troilus, anothertroilus group species, was also significantly reduced by magnolol but not by the biphenyl ether. In contrast,P. glaucus, a polyphagousglaucus group species that feeds on magnoliaceous hosts, was not affected by either compound. The effect of these compounds against a. polyphagous nonpapilionid was examined using the fall webworm (Hyphantria cunea, Lepidoptera: Arctiidae). The biphenyl ether but not magnolol significantly lowered webworm first-instar survival, demonstrating that polyphagy does not preadapt lepidopterans to feeding on this neolignan. These results demonstrate that although phagostimulants play a role in the specialization of thetroilus group on the Lauraceae, the presence of toxins and/or deterrents in nonhosts is also important in determining food plant patterns in these species.
采用生物测定导向分离法从黄兰（Magnolia virginiana）中分离出化感物质，研究了毒素和驱避剂在防止 Troilus 组物种（鳞翅目，凤蝶科）取食木兰科植物中的作用。由三种新木脂素化合物组成的馏分显著降低了第一龄幼虫的存活率，该幼虫是 Troilus 组的一员，红颈凤蝶（Papilio palamedes）。这两种化合物之一，厚朴酚和联苯醚，经单独测试均对红颈凤蝶有毒。另一种 Troilus 组物种，木兰凤蝶（P. troilus）的幼虫存活率也因厚朴酚而显著降低，但联苯醚则没有。相比之下，取食木兰科植物的多食性的蓝凤蝶（Glaucus）组物种，既不受这两种化合物影响，也不受这两种化合物影响。采用秋粘虫（Hyphantria cunea，鳞翅目：夜蛾科）来检测这些化合物对多食性非凤蝶的影响。联苯醚而非厚朴酚显著降低了秋粘虫的第一龄存活率，这表明多食性并没有使鳞翅目昆虫预先适应取食这种新木脂素。这些结果表明，尽管取食刺激物在 Troilus 组对樟科植物的特化中发挥了作用，但非寄主中存在毒素和/或驱避剂在确定这些物种的食物植物模式方面也很重要。
