Abstract:By means of dripping GAs(50 ppm) and NAA(40 ppm) on the hybrid boll-embryo culture in vitro, one F1 plant of G. hirsuturn × G. bickii was obtained in 1982, the Fx plant flowered profusely but failed to produce any seeds when selfed or back crossed. In meiosis of the pollen mother cell (PMC), mean chromosome coniugation was 33.24 Ⅰ +2.67 Ⅱ +0.095 Ⅲ + 0.048 Ⅳ with high frequence (77.6%) of one chiasma attenuated bivalents. Mean number of chiasmta per bivalents was 1.23. The univalents were scattered over the achromatic figure for most PMCs. Although a few of the bivalents were located in‘ the equatorial region, but they did not form a definite plate. At the second anaphase the distribution of chromosomes was very irregular. In the majority of cases, multipolar distripution of chromosomes was observed. At the completion of meiosis highly abnormal sporads occurred, which contained from 2 ro 13 spores of various sizes. Thus, all of the pollen grains produced were sterile. When the F1 branches were grafted onto the upland cotton and thence they were backcrossed under short day (12 hours) and cold night(15–18℃) exposure, BC1 seeds could be harvested. BC1 and BC2 plants could grow up later. In the BC, generation, the fertility of the hybrid was restored. By 1988, ten pure lines of hybrid with the characers of both male parent (viz.red petal with purple spot and strong fibre) and female parent (white fibre, high yield, earliness ect.) were selected for the first time.