Abstract: The mitosis of wheat root cells were studied after the root meristem were treated by trifluralin. Chromosome doubling, multipolar, laggards, unequal division, rings and micronuclei were observed. The results revealed that each treatment concentration and time could induce abnormal splitting, and the highest index was 11.05% (100 μmol·L^-1，12 h). The influence of treatment time was more significant than that of concentration. Chromosome doubling was the most in the abnormal cells, and the rate was 6.25%(100 μmol·L^-1，12 h).

Key words: wheat, root, trifluralin, abnormal splitting