Fertility and Karyotype Remodel in the Dikaryotype Hybrid Lycoris Aurea×L. Radiata

Ming-Shu Yuan ； Chyi-Jang Wu ； Chou-Tou Shii

《Journal of Genetics and Molecular Biology》 9卷4期 (1998/12) Pp. 91-99

https://doi.org/10.30047/JGMB.199812.0002

並列摘要

The interspecific hybridization between two divergent species Lycoris aurea. 2n=14=4A(metacentrics)+3T(telocentrics) and L. radiata. 2n=22=22A (acrocentrics) obtained dikaryotype hybrid 2n=18=4M+3T+11A assignated as Lycoris×Aureadiata. This dikaryotype hybrid exhibited median fertility as high as 60%. The fertility is assumed on synaptic model in formation of four M-2A tripartite bivalents and three T-A heteromorphic bivalents. The gamete analysis of dikaryotype hybrid was mediated through testcross and embryo rescue. The gamete chromosome set reproduced by dikaryotype hybrid was traced as n=7,8,9,10 and 11. Each chromosome set was also discriminable into several recombinant karyotypes containing the some M number but different in A and T combination as expectation, such an n=7=4M+3T, 4M+3T, 4M+2A+1T and so on. The recombinant gametes such as M-A or A-T karyotypes are not existed in natural species. Although, some mutated chromosomes were obsevred, but, all the recovered polymorphic gametes were constituted of constant 11 large arms. It is suggested that the dynamic dikaryotype hybrid is competent to hasten karyotype remodel, and create numerous neo-karyotypes via balanced homeologous disjunction of heteromorphic bivalents. It is also potential to use as breeding bridge benefit for variability selection.

並列關鍵字

Lycoris ； dikaryotype ； synaptic model ； karyotype remoldel