RESEARCH ON CRITERIA OF RESISTANCE TO WHEAT SCAB (GIBBERELLA ZEAE)

Using the inoculation method of injecting wheat scab spores into a single floret in the middle of a wheat spike for three years in succession, three resistance criteria (the period from inoculation to the disease spreading to the rachis, the number of diseased spikelets, the number of diseased internodes on the rachis) were studied. The results indicated that high resistance, medium resistance and Susceptibility could be more clearly differentiated by the number of diseased spikelets, which proved to be the most consistent criterion. We could make a more accurate evaluation of the varietal resistance relying mainly on the number of diseased spikelets while taking the number of diseased internodes on the rachis as an auxiliary index.