| Abstract: | We have studied the influence of various concentrations of chitooligosaccharides (CO) on hydrogen peroxide (H2O2) generation, with the involvement of oxalate oxidase (OO), in rhizoids and in zones of hard brand pathogen penetration, as well as on oxalate oxidase activity in wheat calluses. In the control group, diaminobenzidin (DAB)-staining was typical of 30% of peripheral rhizoid cells, which provided their resistance during infection. In the zone of fungus penetration, the appearance of DAB-stained parenchyma-like cells was observed. Simultaneously, the activity OO cytoplasmic fraction increased, whereas OO activity in its ion-bound fraction was suppressed. Low concentrations of medication induced rhizoid formation, increased the number of DAB-stained cells in the pathogen penetration zone, and induced OO activity in cytoplasmic and ionically cell wall-bound fractions. On the contrary, a high concentration of CO (100 mg/ml) suppressed rhizoid formation, Oo activity and the fungus growth. The discovered correlation between enzymatic activation under CO influence, the high level of protective response during infection, and the intensity of rhizoid formation may suggest the community of protective and morphogenetic mechanisms of reactions in plant cells in respect to hydrogen peroxide production. |
