Andrea N Peña Malavera, Diego Costilla, Aldo S Noguera, Atilio P Castagnaro, Santiago Ostengo and Josefina Racedo
Instituto de Tecnología Agroindustrial del Noroeste Argentino (ITANOA), Estación Experimental Agroindustrial Obispo Colombres (EEAOC) – Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), CCT NOA Sur. Av. William Cross 3150, Las Talitas, Tucumán, R. Argentina, T4101XAC; andreapema@eeaoc.org.ar
Sugarcane brown rust (Puccinia melanocephala) is a disease of major importance in many sugar producing regions of the world, causing significant yield losses and economic impacts. The most effective method for controlling this disease is the use of resistant commercial varieties. The availability of diagnostic markers to detect the presence of the major gene Bru1 has allowed the study of its efficacy and frequency in sugarcane germplasm, revealing that in some cases resistance to brown rust in modern varieties is essentially due to the Bru1 gene. To identify alternative genetic sources of resistance, a selective genotyping study was previously conducted in a biparental population, identifying SNPs associated with brown rust resistance. The present study aimed to perform association mapping in a population composed of 305 accessions from the EEAOC germplasm bank, genotyped with >9000 SNPs derived from DArT seq and phenotyped for brown rust in the field under high natural inoculum pressure. A total of 10 SNPs were found to be associated with resistance. The localization of these markers on the sugarcane genetic map will allow for the identification of the regions that control this trait of interest, making them available to the scientific community and breeders.