Research Advances on Cytogenetics of Avena (Pooideae, Poaceae)

Abstract:

The research advances and future research directions for cytogenetics of Avena L.(Aveneae,Pooideae,Poaceae) were summarized by reviewing related literature.The 29 species of Avena were belonging to seven sections and five types of genomes (A,C,AB,AC,and ACD).Based on fluorescence in situ hybridization (FISH) and chromosome pairing experiments between the interspecific F₁ generation hybrids,the major differences of chromosome structure were presented between A and C genomes——the isobrachial chromosomes in the A-genome diploids and the heterobrachial chromosomes in the C-genome diploids.Molecular phylogenetic data supported a close relationship between D and A genomes,while the B genome was similar to the A’ genome according to the cytogenetic data in Avena.The hypothesis of A-genome diploids being the maternal parents for hexaploid species of Avena occupied mainstream status,while Avena strigosa being the maternal A-genome donor for Avena polyploids were questionable,further some researchers thought that A.canariensis might be the A-or D-genome donor for Avena polyploids.Intergenomic interchange or chromosome rearrangement occurred during the divergence of Avena polyploids,resulting in more difficulties in researches of the interspecific relationship reconstruction,the genomic origin,and speciation process of polyploids in Avena.Therefore,the combination of genomics and molecular cytogenetic technologies might provide new evidence for above cytogenetic problems.

Key words:Genome origin;Avena;Cytogenetics;Poaceae;Polyploid