Abstract:The young-ears of “Yugu No. 1”, a millet (Setaria italica (L.) Beauv. ) variety of good quality, high yielding and stress-resistance, were chosen to induce callus on N6 medium. After 3—5 times of subcultures, the callus was treated with colchicine (0.02%) for 48 hours and then transferred hack to subculture medium to restore growth, after which the callus was transferred to differentiation medium and subsequently, tetraploid plants were obtained. Through crossing, using tetraploid plants as female parent and diploid plant as male parent, 5 triploid plants were found among 2100 offspring plants. The triploid plants were fertilized with pollens from diploid plants. Among the plants developed from the seeds harvested on triploid plants, 9 kinds of trisomics (totally 283 plants) were identified according to chromosomal number and morphologic feature. Each kind of the trisomics has specific marker feature: (Figures in parentheses represent the number of plants obtained) Triplo-1 (52) has rolling leaves, Triplo-2 (18) is dark green, Triplo-3 (43) is bushy and has degenerated spikelets at the tip of panicles: Triplo-4 (58) has long bristle: Triplo-5 (16) has slender stalks: Triplo-6 (36) has twisted panicle neck; Triplo-7 (44) is semi-erect; Triplo-8 (8) has thick panicles; Triplo-9 (8) is pseudonormal (Similar with diploid of “Yugu No. 1”).