Lectin Binding Sites On Mobile Stages of Heterodera Schachtii Schmidt (Nematoda: Heteroderidae)

Abstract

Lectins of Canavalia ensiformis (Con A), Triticum vulgare (WGA), Phytolacca americana (PWM), Helix pomatia (HPA), Arachis hypogaea (PNA), Lotus tetragonolobus (LTA), Limulus polyphemus (LPA) and Limax flavus (LFA) were tested for binding to surface glycoconjugates of Heterodera schachtii males and second stage juveniles from aseptic culture. The lectins were labelled with fluorochromes and the fluorescence was examined using incident fluorescence microscopy. All lectins, with the exception of PWM and LTA, bound at the amphid openings. HPA bound also to the cuticle, mainly in the head and tail region, and at the excretory pore. PNA bound to the stylet-tip of males and to parts of the head cuticle of second stage juveniles. PNA (only in males) and LTA adhered to the region of the inner labial sensilla. The spicule tips were labelled with Con A, WGA, HPA and PNA. In second stage juveniles, Con A also bound at the excretory pore and to the cuticle. Binding specificity was shown by inhibition with the appropriate sugars. The presence of carbohydrates on the lectin binding sites and their possible role in sex and host plant recognition are discussed.