Journal of Plant Pathology & Microbiology

The DNA landscape in Avena: Chromosome and genome evolution defined by major repetitive DNA classes in whole-genome sequence reads

8^th World Congress on Plant Genomics and Plant Science

August 10-11, 2018 Osaka, Japan

Qing Liu

Chinese Academy of Sciences, China

Posters & Accepted Abstracts: J Plant Pathol Microbiol

Abstract:

Cultivated oat (Avena sativa) was inferred to experience ancient allotetraploidy and subsequent recent allohexaploidy events involving C-, A-, and D-genome ancestors (x=7). Whole-genome sequencing followed by k-mer and RepeatExplorer clustering analyses enabled assessment of repetitive DNA composition in cultivated oat and its wild relatives??? genomes. Fluorescence In Situ Hybridization (FISH)-based karyotypes were developed to understand chromosome and repetitive sequence evolution of cultivated oat. Repetitive DNA proportions were 71.962%-73.596% with the more abundant gypsy (42.882%- 44.004%) than copia (15.938%-17.445%) retrotransposons in four Avena species genomes. FISH karyotype of cultivated oat was constructed by using twenty-five genome-specific probes, all chromosomes involved intergenomic translocations. The mean recombination rate varied from 0.0411 of chromosome pair number (cpn) 39/40 up to 0.2430 cM/Mbp of cpn 27/28 and the recombination rate of C-Genome Chromosomes (GC) is higher than that of A/D-GC. The results provide a molecular toolkit to characterize repeat abundance and sequence composition in Avena genomes, determine different maternal progenitors involved in multiple hybridization events of Avena sativa and facilitate genetic improvement of this vital crop. In addition, the study generated various data resources that are available for future exploration of the Avena sativa genome.

Biography :

E-mail: liuqing@scib.ac