Male sterile plants from the hybrid seeds of male sterile plants were always heterozygous (Ms2ms2) for the dominant sterility gene, and fertile plants from the hybrid seeds were homozygous (ms2ms2) for the recessive alleles. If male sterile seeds could be distinguished from fertile seeds in a simple way, it would be more convenient to use dominant male sterility in hybrid seed production. Aneuploids in different common wheat background were produced based on the durum wheat addition line 89-2343 (Tian 1991). After extensive backcrosses, a female gamete with a translocation segment containing Ms2ms2Rht10rht10 in 4D/4E was fertilized. It was finally developed into a combination line with blue seed marker, Rht10 and Ms2. Thus, the fertility of plants could be easily identified according to their seeds color. Meanwhile, transmission rate of additional chromosome 4D/4E was stable during different years. So, female plants from blue seeds will display uniform male sterility, and recurrent selection could be conveniently carried out in wheat breeding program.
Blue seeds, short plants and shriveled anthers controlled by the blue seed genes, Rht10 and Ms2respectively, are easily identified in laboratory andfield. Nearly all modem wheat varieties and elite lines could be transferred into the blue marker male sterile lines through backcrossing. When blue marker male sterile lines are crossed with normal varieties, about 80% of the hybrid seeds with a white color will generate normal fertile plants. The fertility of these plants is not affected by restoring gene and so the possibility for breeding new crosses or hybrids is increased. Because the additional chromosome usually has lower transmission ratio in most recurrent parents, so the propagation coefficient of blue male sterile seeds was very low. If the blue kernel gene could be transferred to chromosome 4D, a blue marker male sterile line with 21 pairs of chromosome, would be more effective and stable than addition lines. In this study, it is very interesting that the transmission ratio for blue seed marker, Rht10 and Ms2 in genotype 477A was nearly 50% in three seasons. It is still not clear whether the blue seed marker has been transferred to chromosome 4D or not.