Tissue Cultural Characterization of H aploid Coleoptilar Node in Maize

Objective) The aim of this research is to test and characterize maize haploid plants generated from coleoptilar node by means of tissue culture in order to create a new method to obtain doubled-haploid lines. (Method) The haploid coleoptilar nodes of 20 hybrid F1 combinations came from Reid, Huangzaosi and Tem-tropicⅠ group, respectively, were submitted to induction and differentiation frequency test. Both chromosome number of root tip cells and pollen fertility in regenerated plants were analyzed. Forty-seven SSR makers were used to evaluate the genotype of the regenerated haploid plants. (Result) The callus induction frequency was significantly higher in Reid and Huangzaosi groups than that of Tem-tropicⅠ group. All the root tip cells from 15 regenerated plants were found to contain only 10 chromosomes, suggesting that they were haploid plants. After colchicines treatment, I-KI staining of the pollen grains in shedding anthers revealed that they partially sterile. Based on SSR makers date, it was noted that all the genotypes of regenerated haploid plants originated from the recombination of their two parents. (Conclusion) Reid and Huangzaosi groups were much better than Tem-tropicⅠ group in terms of maize haploid plant generation through tissue culture.