Abstract:The novel approach we created for in vivo induction of homogeneous autopolyploid (IVIHA) via callus could effectively avoid mixploid formation and rapidly obtain pure polyploid in Chinese jujube (Ziziphus jujuba Mill.). In vivo bud regeneration via callus (IVBR) is the basis of successful application of this new approach. Using this approach, the abilities of IVBR of 115 Chinese jujube genotypes and 4 sour jujube (Z. acidojujuba Cheng et Liu), the wild ancestor of Chinese jujube, were evaluated, and 4 genotypes of Chinese jujube were chosen for polyploid induction. The results showed that 94.78% Chinese jujube genotypes and 100% sour jujube genotypes formed calluses, and 80% Chinese jujube genotypes and 100% sour jujube genotypes regenerated buds via callus. The callus formation ratio differed with genotypes, ranged from 0%-100%, averaged of 76.48% with variation coefficient of 37%; Based on callus formation ratio the tested genotypes were classified into 5 groups, i.e., genotypes easy for callus formation, genotypes less easy for callus formation, genotypes less difficult for callus formation, genotypes difficult for callus formation and genotypes with no callus formation. The bud regeneration rate (average bud number per branch cross section) was also significantly different (0-10.33) among genotypes with average of 1.84, and thereby the tested genotypes were divided into 5 groups according to their bud regeneration rate. There is no significant co-relationship between callus formation ratio and bud regeneration rate, in other words, genotypes with high callus formation ratios not always have high bud regeneration rates. With the IVIHA approach (combining in vivo bud regeneration via callus with colchicines inducement), pure tetraploid germplasms of 3 Chinese jujube genotypes (Leling 1, Ningxiachangzao, Yunchengpopozao) and 1 pure triploid germplasm (Mopanzao) were firstly created.