Phytotoxicity of constituents of glandular trichomes and the leaf surface of camphorweed, Heterotheca subaxillaris

Phytochemistry. 2009 Jan;70(1):69-74. doi: 10.1016/j.phytochem.2008.09.026. Epub 2008 Dec 4.

Abstract

Camphorweed, Heterotheca subaxillaris (Lam.) Britt. & Rusby, has a camphor-like odor, and its leaf surfaces contain glandular trichomes of the type shown to contain high levels of isoprenoids in other species. Borneol (1), the phytotoxic calamenene-type sesquiterpenes (2-5, 9-11), and methylated flavones (12-15) were isolated from the dichloromethane rinsate of camphorweed aerial tissues. The strongest plant growth inhibitor against Agrostis stolonifera and Lactuca sativa seedlings, as well as duckweed (Lemna pausicostata), was 2-methoxy-calamenene-14-carboxylic acid (2). Esterification of calamenene carboxylic acids decreased their biological activity.

MeSH terms

  • Agrostis / drug effects
  • Asteraceae / chemistry*
  • Asteraceae / ultrastructure
  • Camphanes / chemistry*
  • Camphanes / pharmacology
  • Flavones / chemistry*
  • Flavones / pharmacology
  • Herbicides / chemistry
  • Herbicides / pharmacology
  • Lactuca / drug effects
  • Molecular Structure
  • Plant Leaves / chemistry*
  • Plant Leaves / ultrastructure
  • Seedlings / drug effects
  • Sesquiterpenes / chemistry*
  • Sesquiterpenes / pharmacology
  • Structure-Activity Relationship

Substances

  • Camphanes
  • Flavones
  • Herbicides
  • Sesquiterpenes
  • isoborneol