The ratio of resistant and susceptible plants was 1:1 in progenies of backcross of the F1 and susceptible parents, and this ratio was 2.8:1 in the F2 generation from the F1 selfing.

• 抗性稳定株系与感病亲本杂交，F1表现高抗病，再与感病亲本回交，后代抗感病株比例为1:1，自交F2的比例为2.；8:1。