1981 Volume 47 Issue 5 Pages 646-653
The relationship between plant hormones and shift of peroxidase activity in the rice blast lesion was investigated using a compatible race-cultivar combination. Peroxidase activities in the leaf tissues were increased by the application of auxins, ethylene or their precursors, especially at the inoculated site. When kinetin was subsequently applied, the increase in the peroxidase activity by IAA or ethylene was enhanced, on the other hand, the increase by IAA or ethylene was suppressed by the subsequent application of ABA. The degree of rice blast incidence was suppressed by the application of auxins, ethylene or their precursors. The suppression of blast incidence by IAA or ethylene was strongly counteracted by the application of ABA prior to inoculation. The metabolic inhibitors such as formycin A, cycloheximide and blasticidin S caused considerable inhibition of IAA-or ethylene-induced increase in peroxidase. The hypothetical role of plant hormones on induced disease resistance of rice plant was proposed.
