Phylogenetic Relationships Of Avena Species Based On Fluorescent In Situ Hybridization

The genus Avena L.belong to the tribe Aveneae,subfamily Pooideae,Poaceae,consists of approximately 30 species.The genus Avena comprise of four genomes: A,B,C and D.And there are four polyploid species with AB,AC or CD,CC and ACD genomes.Due to the complexity of ploidy and genomic composition,together with the overlap of geographical distribution and the similarity of morphological characters,there are many problems in the evolution and classification of Avena species.As a result,clarifing the classification of Avena species and the origin of polyploid species,which are important to improvement oat variety and breed new varieties.Base on those problems,we utilized oligonucleotide probes together with the 45 S and 5S probes for FISH analysis of Avena species to distinguish the different chromosomes and explore the relationship between different species.1.45 S probe is regularly distributed on the satellite chromosome.5S probe is mainly distributed on the A and D genomes of Avena species.2.For the diploid species,there are signal polymorphism in various species of the A-genome.We can inferred that A.lusitanica and A.damascena have high homology.The present study showed the most A genome species A.brevis(As),A.wiestii(As),A.atlantica(As)and A.longiglumis(Al)have similar signal patterns,at the same time,A.nuda(As)and A.canariensis(Ac)have similar signal patterns.This oligonucleotide probes are dissimilarly distributed in A.clauda(Cp),A.eriantha(Cp)and A.ventricosa(Cv).3.Based on present study we can inferred that the origin of AB-genome tetraploid can be divided into three branches.A.abyssinica and A.vaviloviana belong to the same origin.A.agadiriana and A.barbata belong to different origins.The signals are dissimilar between A-genome and B-genome.Ad-genome diploid might be served as the B genome donor of AB-genome tetraploid Avena.As-genome diploid might be served as the A genome donor of AB-genome tetraploid Avena.It can be inferred that among the three AC-genome tetraploids,A.maroccana and A.insularis are more closer than it with A.murphyi.we suggest the genome constitution of the three AC(CD)-tetraploid species is preferred CCDD rather than AACC.4.The difference is not obvious between the hexaploid species.As-genome diploid might be served as the A genome donor of ACD genome hexaploid species.A.canariensis(Ac)might be served as the D genome donor of ACD genome hexaploid species.The present study showed that A.maroccana and A.insularis have similar signal patterns with hexaploid species,especially A.sterilis.