对４个不同材料各一个基本株自交产生的姊妹系及其姊妹种、以及由此配成的普通单交种和改良单交种的若干农艺性状进行分析的结果表明：１）利用早代姊妹种（Ｓ２或Ｓ３）进行制种，可以提高制种产量６０％以上，有的材料Ｓ２代姊妹种的制种产量甚至成倍增加。不同材料相同世代的姊妹种间增产幅度不一。２）同一材料不同Ｓ２代姊妹种间增产潜力存在明显差异，其增产幅度为１５２６％～８３．９６％。扩大早代姊妹系间遗传变异的选择范围，可进一步发挥姊妹种高产制种的优势潜力。３）４个Ｓ２代姊妹种与对应姊妹系各自和彼此之间的产量配合力效应相一致，保证了改良单交的产量和整齐度与普通单交种相近。４）与不育胞质相结合，既可提高制种产量，又可确保种子质量，进一步拓宽改良单交种的利用前景。 The results of the analysis of several agronomic traits derived from inbred-sister lines and their siblings from one of four different materials, as well as the common and improved single crossbreds, showed that: 1) Seed production by sibling species (S2 or S3) increased seed production by more than 60%, while seed production by S2 siblings in some species even doubled. Different breeds of siblings of the same generation with different materials have different increases in yield. 2) There was a significant difference in the yield potential of the same material among the sister sires in S2 generation, with the rate of increase of 15.26% -83.96%. Expanding the range of genetic variation among sister lines in the early generation can further exploit the potential advantages of high-yielding sires. 3) Consistency of the yield combining ability between the 4 siblings of S2 generation and the corresponding sister lines and each other ensures that the yield and uniformity of the improved single cross are similar to that of the common single cross. 4) Combining with sterile cytoplasm can not only increase the seed yield, but also ensure the seed quality and further broaden the utilization prospects of improved single cross breeding.