Analysis of variation for phenotypic traits of key maize inbred lines in China

Based on the pedigree, 66 maize inbred lines, which were mainly bred during the past 30 years were classified into four clusters (Huangzaosi, Mo17, 478 and Dan340). They were planted at three independent ecological locations in 2008 and 2009, and then the data of phenotypic traits (such as growth period, plant height, ear height, plant yield.) were collected. The results showed that leaf number and growth period were stably inherited within cluster Huangzaosi. And, within cluster Mo17, the traits of ear diameter, 100-kernel weight and kernel depth could be stably inherited. Lov, 100-kernel weight and ear length could be inherited within cluster 478. Rows per ear might be inherited within cluster Dan340. To efficiently utilize these key inbred lines, we should pay more attention to early growth period of Huangzaosi, high kernel weight of Mo17, rows per ear of Dan340 and some important traits of 478, or improve some other lines with those excellent traits within each cluster.   Key words: Maize, key inbred line, phenotypic trait, inherit.