Dual chemical barriers protect a plant against different larval stages of an insect

• Published in: Journal of chemical ecology Vol. 27; no. 8; pp. 1575 - 1583
• Main Authors: RENWICK, J. Alan A, WENQING ZHANG, HARIBAL, Meena, ATTYGALLE, Athula B, LOPEZ, Kimberly D
• Format: Journal Article
• Language: English
• Published: New York, NY Springer 01.08.2001; Springer Nature B.V
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; Animals; Autoecology; Bioassays; Biological and medical sciences; Biological Assay; Brassicaceae - chemistry; Butterflies & moths; Fundamental and applied biological sciences. Psychology; Glucosides - isolation & purification; Glucosides - pharmacology; Glycosides - isolation & purification; Glycosides - pharmacology; Herbivores; Host plants; Insects; Invasive plants; Larva - growth & development; Larvae; Lepidoptera; Nitriles - isolation & purification; Nitriles - pharmacology; Oviposition; Plants and fungi; Plants, Edible - physiology; Survival Analysis; Monocotyledones; Introduced species; Weed; Insecta; Flavonoid; Liliaceae; Pest; Vegetable crop; Animal plant relation; Arthropoda; Angiospermae; Lepidoptera; Antifeedant; Pieridae; Defense mechanism; Spermatophyta; Invertebrata
• ISSN: 0098-0331; 1573-1561
• DOI: 10.1023/A:1010402107427

The host plants of the native American butterfly, Pieris napi oleracea, include most wild mustards. However, garlic mustard, Alliaria petiolata, a highly invasive weed that was introduced from Europe, appears to be protected from this insect. Although adults will oviposit on the plant, most larvae of P. n. oleracea do not survive on garlic mustard. We used feeding bioassays with different larval stages of the insect to monitor the isolation and identification of two bioactive constituents that could explain the natural resistance of this plant. A novel cyanopropenyl glycoside (1), alliarinoside, strongly inhibits feeding by first instars, while a flavone glycoside (2), isovitexin-6"-D-beta-glucopyranoside, deters later instars from feeding. Interestingly, the first instars are insensitive to 2, and the late instars are little affected by 1. Furthermore, differential effects of dietary experience on insect responses suggest that 1 acts through a mechanism of post-ingestive inhibition, whereas 2 involves gustatory deterrence of feeding.