Subcellular localization of chitinase and beta-1,3-glucanase in compatible and incompatible interactions between wheat and Puccinia striiformis f. sp tritici

摘要

Two antisera raised against acidic chitinase and acidic beta-1,3-glucanase from tobacco were used to investigate the subcellular localization of the two enzymes in the compatible and incompatible interactions between wheat and Puccinia striiformis f. sp. tritici by means of the immunogold labelling technique. The studies demonstrated that the labelling patterns for both enzymes were very similar in the uninoculated and infected wheat leaves. The enzymes were localized mainly in he host cell walls, while no labelling was observed in cytoplasm and organelles. However, the accumulation of chitinase and beta-1,3-glucanase in the infected wheat leaves differed markedly between resistant and susceptible wheat cultivars. The labelling densities for the two enzymes in the infected leaves of the susceptible cv. 'Huxianhong' increased slightly as compared to the uninoculated leaves, whereas significantly higher labelling densities of chitinase and beta-1,3-glucanase were found in the infected leaves of the resistant cv. Xinong 85' compared to the uninoculated leaves. Furthermore, the labelling of chitinase and beta-1,3-glucanase also occurred over the extrahaustorial matrix and the fungal cell walls in the infected wheat leaves. The extrahaustorial matrix and the hyphal cell walls in the infected leaves of the resistant cv. 'Xinong 85' usually showed a higher density of the labelling than those in the susceptible cv. 'Huxianhong'. In addition, the two enzymes were also detected over the cell wall appositions in the infected leaves of the resistant wheat cultivar. The potential role of chitinase and beta-1,3-glucanase accumulation in the defense reactions of the incompatible interaction of wheat cv. 'Xinong 85' and P. striiformis f. sp. tritici is discussed.