Abstract: 【Objective】 Research on marker-assisted methodology of developing germplasm suited as female and male parents was of practical importance in improving utilization efficiency of this source and promoting the development of maize breeding, since single-cross hybrids are over 95% in maize production. 【Method】 A popcorn hybrid, "JB1", was used as the initial entry in the present study to obtain polymorphic simple sequence repeat (SSR) markers and determine the parents’ genotype by performing polymerase chain reaction (PCR) amplification with genome-wide SSR markers and native polyacrylamide gel electrophoresis (PAGE). Subsequently, marker-assisted selection was performed in progenies of F₂ and two later subsequent generations using the polymorphic markers distributed evenly on the ten chromosomes of maize. As a result, three groups of progenies were obtained, i.e. male parent-like, female parent-like and middle type. To evaluate the heterosis and the breeding value of these selected progenies, hybrid combinations were made by using incomplete diallel cross in F₄ among the progenies from the male-like and female-like group which selected by marker-assisted selection. Testcrosses were also made between three testers and the materials selected by marker-assisted selection and breeding experience in early generation, respectively. Yield experiments and comprehensive evaluation of 2 780 hybrids were then conducted in Shunyi of Beijing and Yuxian of Hebei. 【Result】 Marker-assisted selection significantly improved the selection efficiency in the separate communities. In the F₄ generation, the similarity to the male parent and the female parent of selected materials could be as high as 79.5% and 73.7%, respectively. The similarity to the parents was much higher than that under the condition of random selection. Genetic distance between the materials from the male-like group and the female-like group was large and the maximum was 86%. Phenotypic analysis showed that the average plot yield of hybrid combinations between the male-like group and the female-like group was higher than that of hybrid combinations within each of the two groups, and there were no combinations whose yield exceeded the control (the original hybrid, JB1). Meanwhile, the testcrosses generated from the male-like materials displayed stronger heterosis and had higher plot yields than those generated from the female-like materials and the materials selected by breeding experience. There also existed some hybrid combinations whose yields exceeded the control. 【Conclusion】The study proposed a technical route of SSR marker-assisted germplasm development based on maize hybrids which could be useful in promoting use efficiency of maize hybrids.

Key words: maize, hybrids, germplasm resources, marker-assisted selection, germplasm development