Cytochemistry of the Interaction between Wheat (Triticum aestivum) and Puccinia recondita f.sp. tritici Localization of Cellulose, Chitin, Glucose/Mannose, Galactose and Fucose

Abstract

AbstractA study of the cytochemistry of the interaction between wheat and Puccinia recondita f, sp. tritici, using various enzyme‐ and lectin‐conjugated colloidal gold probes provided additional information on the nature and composition of the walls of fungal hyphae, the haustorial mother cell, the haustorial neck, the haustorial body, and the extrahaustorial matrix. Using a cellulase‐conjugated gold probe, cellulose (the major component of the host cell wall) was not detected in the extrahaustorial matrix or in the host tubules associated with the invading haustorium. Wheat germ agglutinin (WGA)‐gold conjugates, which detect chitin oligomers (N‐acetylglucosamine residues), bound to two inner wall layers of the intercellular hypha, four inner wall layers of the haustorial mother cell (HMC), and the wall layers of older haustorial bodies, WGA did not bind to the haustorial neck, the walls of the young haustorial body or the extrahaustorial matrix. Concanavalin A‐ (ConA‐) and Lentil agglutinin (LTA)‐gold complexes, which specifically recognize man‐nose/glucose residues, bound to the wall layers of intercellular hyphae, HMCs, haustorial necks and young haustorial bodies. Colloidal gold conjugates with peanut agglutinin (PNA) which detect galactose residues, soybean agglutinin (SBA) which are specific to both galactose and N‐acetylgalactosamine residues, and Helix pomatia agglutinin (HPA) which recognizes N‐acetylgalactosamine residues, respectively, bound to these residues in the sections, PNA and SBA labelled the cell walls of intercellular hyphae, HMCs, haustorial necks, young haustorial bodies and the extrahaustorial matrix, PNA and SBA also bound to the host cell wall and to the host extracellular matrix, HPA bound weakly to the walls of haustorial bodies and the extrahaustorial matrix, Ulex europeaus agglutinin (UEA 1)‐gold complex, specific to α‐fucose residues, bound to the wall layers of intercellular hyphae and HMCs, and bound weakly to the extrahaustorial matrix. The composition of wall layers of the haustorial body of P. recondita f, sp, tritici appears to change as the haustorium matures.