Multilocus Sequence Analysis highlights genetic diversity of Acidovorax avenae strains associated with sugarcane red stripe

FONTANA, P.; TOMASSINI, N.; FONTANA, C. ; COCCONCELLI, P.S.; VIGNOLO, G.; SALAZAR, S.

Tucumán

Congreso; XXX Congreso International de la Caña de Azucar; 2019

Society of sugar cane technologyst

Pathogenic species of Acidovorax cause economically important diseases in monocotyledonous and dicotyledonous crops, including sugarcane, corn, rice, oats, millet, foxtail, watermelon and orchids. Sugarcane red stripe, caused by Acidovorax avenae, is present in the main production areas around the world. In Argentina, red stripe affects about 30% of stalks milled with important economic losses when severe infections occur. MLST was used to explore the genetic diversity of this bacterium associated with red stripe in Argentina, as well as their phylogenetic relationships. The MLST analysis included sequences from a total of 118 Acidovorax, 15 A. avenae strains isolated from Argentina sugarcane production areas, A. citrulli (93) from melon and watermelon, A. avenae (9) from rice, millet, corn, vasey grass and sorghum, and A. oryzae (1) from rice. MLST analysis revealed five novel sequence types (STs) for the sugarcane A. avenae strains, constituting a clonal complex with a common and close origin. When genetic relationships with other Acidovorax were explored, sugarcane strains were related to A. avenae from other hosts and more distantly to A. citrulli. Signals of frequent recombination in several lineages of A. avenae were detected and we observed that A. oryzae is closely related to A. avenae strains. This study provides valuable data in the field of epiphytological and evolutionary investigations of A. avenae strains causing sugarcane red stripe. Knowledge of the genetic diversity and host-strain.