Progress towards the generation of a reference genome of diploid Paspalum notatum

ORTIZ JPA; SIENA LA; GRISOLIA M; ROHR C; VAZQUEZ M; PODIO M; PESSINO SC; MARIAC C; LEBLANC O

Mendoza

Congreso; ALAG 2019; 2019

Sociedad Argentina de Genética

Paspalum notatum is a multiploid grass species found in natural pastures of South America. The diploid cytotype is sexual and self-sterile, while polyploid ones (3x, 4x and 5x) are pseudogamousaposporous apomicts. Some diploids can form aposporous sacs at low frequencies. Apomixis in the species is controlled by a single non-recombinant region (ACR) that remains poorly characterized. Our objective is to produce a genome draft of the species to be used as reference for mining genes governing apomixis and other agronomically important traits. DNA from the diploid genotype R1 was sequenced using HiSeq-Illumina and Oxford Nanopore technologies. Sequencing outputs reach up to 100x (HiSeq Illumina) and 48x (Nanopore) coverage. Assembly with MINIASM produced 3,843 sca olds of N50= 299,668 bases. The genome completeness estimated by BUSCO was 99 % . Sca olds carrying apomixis-related sequences were identi ed by BLASTn analyses using genes and markers linked to the trait as query. Sca olds carrying homologous sequences for 122 rice genes, coding for proteins involved in hormone signaling, development and cell proliferation were identi ed. Several of them were associated with reproduction. Results presented here will contribute to determine the structure and evolution of the P. notatum genome and the functional role of the ACR in apomixis.