Composition en métabolites primaires de la surface foliaire du poireau: étude comparative, incidence sur la sélection de la plante-hôte pour pondre par un insecte

Abstract

Summary: Chemical analyses of leek leachates show a large variety of metabolites as already observed on different plant species (corn, sunflower, tansy ragwort), especially free amino acids (21) and soluble carbohydrates. Leek leachates i) permit leek discrimination from other plant species by free amino acids proportions, ii) show caracteristic unknown ninhydrine positive substances and iii) higher levels of fructose, glucose and sucrose than leachates from young maize plant. These last substances, known to be active in the oviposition site preference of the generalist lepidoptera Ostrinia nubilalis Hbn., are still active in the host oviposition preference between leek and young corn plant. However, the highest number of eggs masses laid on leek leaves come off, and first instar larvae do not feed. © 1996, Taylor & Francis Group, LLC.