Progress towards the generation of a reference genome of Paspalum notatum

SIENA LA; VASQUEZ M; PESSINO SC; GRISOLIA, MAURICIO; PODIO M; LEBLANC O; ORTIZ JPA; ROHR, CRISTIAN; CÉDRIC M

Mendoza

Congreso; XVII CONGRESO LATINOAMERICANO DE GENÉTICA; 2019

Sociead 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 scaffolds of N50=299,668 bases. The genome completeness estimated by BUSCO was 99%. Scaffolds carrying apomixis-related sequences were identified by BLASTn analyses using genes and markers linked to the trait as query. Scaffolds carrying homologous sequences for 122 rice genes, coding for proteins involved in hormone signaling, development and cell proliferation were identified. 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.