Cytomorphological Characterization of the Backcross Progeny of Synthetic Amphiploid Rice (AABB) and Tetraploid Oryza sativa (AAAA)


  •  Xianhua Zhang    
  •  Wei Wang    
  •  Junjie Jin    
  •  Shengrong Liao    
  •  Xiaonan Liu    
  •  Zhaojian Song    
  •  Detian Cai    

Abstract

DCW008, a synthetic allopolyploid rice (2n = 4X = 48, AABB), was obtained from chromosome doubling of interspecific hybrids between Oryza sativa (2n = 24, AA) and O. punctata (2n = 24, BB). The F1 and backcross (BC1) hybrids were produced by crossing DCW008 as a female parent with a high seed set tetraploid rice Sg99012 - 4X (2n = 4X = 48, AAAA). BC1F1 and BC1F2 overcame many of the wild-type traits of DCW008; they had yellow-hulled grains, seed set ranged from 0% to 71.31% and the grain morphology was similar to that of cultivated rice. Variable numbers of chromosomes were observed in pollen mother cells (PMCs) from the BC1 plant. Genomic in situ hybridization (GISH) revealed that the majority of somatic cells and PMCs contained six chromosomes of O. punctata with fragment recombination observed in two of them. The backcross selection method employed in this study to generate allopolyploid progeny provides a reliable way of transferring useful genes from wild species into cultivated rice.



This work is licensed under a Creative Commons Attribution 4.0 License.