中文摘要：

【目的】基于水稻单片段代换系聚合而成的品系,是分子设计育种过程中的中间材料,通过评价其优劣,为育种和生产实践提供有益的参考.【方法】以25个聚合系为材料,在2013年早、晚两季采用随机区组试验测验它们与华粳籼74主要农艺性状的差异显著性,并探讨所考察性状的表型和相关的遗传基础.【结果和结论】5个聚合系P05、P08、P14、P15和P21的产量显著地高于华粳籼74,适于早、晚季种植;另2个高产聚合系P07和P12则仅适于晚季种植.所有考察性状的遗传率变动在0.885 9~0.993 7之间,其中,普通遗传率为0.554 7~0.968 8,互作遗传率为0.024 9~0.331 2.着粒密度降低产量,贡献率为15.5%;而千粒质量增加产量,贡献率达36.6%.试验结果为这些性状的遗传改良和育种上的间接选择提供了依据.

英文摘要：

【Objective】Pyramiding lines derived from single segment substitution lines in rice are intermediate materials in the process of molecular design breeding,so it would provide helpful consults for breeding and production practice via evaluation of their phenotypes. 【Method】Twenty-five pyramiding lines were applied as experimental materials,and planted in the field with randomized block design in early and late seasons in 2013 respectively to test the differences of important agronomic traits between each of them and Huajingxian 74. The genetic basis of phenotypes and correlations of all observed traits were explored. 【Result and conclusion】The grain yields of 5 pyramiding lines P05,P08,P14,P15 and P21 were markedly higher than that of Huajingxian74,which were suitable for planting in early and late seasons. The high-yield lines P07 and P12 were merely suitable for planting in late season. The heritability ratios estimated for all observed traits varied from 0. 885 9 to 0. 993 7,of which the general heritability ratios were 0. 554 7- 0. 968 8 and the interaction heritability ratios were 0. 024 9- 0. 331 2. Two traits of seed density and thousand seed mass were detected to influence grain yield,with the former decreasing it by the contribution ratio of 15. 5% while the later increasing it by 36. 6%. The results provide a basisof genetic improvement and indirect selection in breeding practice for these investigated traits.