Asynaptic Mutants of Sorghum Induced in Tissue Culture

摘要

Analysis and comparison of different asynaptic and desynaptic mutants have a great value for investigating mechanisms of chromosome pairing and the role of genes controlling this process. Tissue culture is an efficient tool for obtaining these mutants. previously, the authors revealed that some diploid regenerates from a cell line obtained from a leaf of sorghum haploid cv. Milo 145 were heterozygous for recessive mutations that induced complete sterility of male and female generative structures (Elkonin et al. 1994). Cyto-logical analysis of meiosis in sterile plants from one of the regenerate families showed that induced mutation caused significant abnormalities in the chromosome synapses during prophase I, which resulted in the formation of unpaired univalents and open bivalents. Lagging chromosomes, and univalents divided into chromatids were observed in anaphase I. As a result of these processes, multiple micronuclei were formed in diad cells.