FROM ALFALFA TO SOYBEAN: IDENTIFYING BENEFICIAL MUTATIONS TO EDIT MULTIPLE BACTERIAL LOCI BY CRISPR-CAS9 SYSTEM

GALINDO SOTOMONTE L ; GABRIELA SOTO; FRARE ROMINA; LIEBRENZ KAREN; PASCUAN CECILIA; AYUB NICOLÁS

Congreso; reunión conjunta SAIB-SAMIGE 2020; 2020

Alfalfa is the main forage worldwide due to its high biomass production, excellent nutritional qualities and adaptation to a wide range of environments. In addition to its indirect impact on human nutrition, alfalfa is also the most important legume crop in cultivated area worldwide after soybean (around 30 and 120 million ha, respectively). The evolutionary and economic successful of the legumes species is principally due to their symbiotic association with nitrogen-fixing bacteria (i.e. rhizobia). We recently have shown that commercial alfalfa inoculants (strains B399 and B401), which are closely related to the model alfalfa symbiont S. meliloti 1021 (99.99% of nucleotide identity at genomic level), have lost an extensive number of genes during rhizobial domestication, and that this complex evolution process determines the effectiveness of legume?rhizobia symbiotic interaction under field conditions (J Mol Evol 2017 PMID: 28828631; J Biotechnol 2017 PMID: 29050878, Microbiol Ecol 2018 PMID: 29330647; Microbiol Ecol 2020 PMID: 31828388). To understand this process deeply and to extend the benefits of this knowledge to other public legume breeding programs (mainly, the massive production of knockout soybean rhizobia via CRISPR-Cas9 genome-editing system), we performed bioinformatics analyses for the identification and functional classification of missing genes (both pseudogenes and deleted genes) and studied their occurrence in other important rhizobia including soybean inoculants