ITA-NOA   24624
INSTITUTO DE TECNOLOGIA AGROINDUSTRIAL DEL NOROESTE ARGENTINO
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Molecular tagging of novel sources of resistance to sugarcane brown rust for use in breeding
Autor/es:
ALVES-PEREIRA, A.; CASTAGNARO, A. P.; OSTENGO, S.; CUENYA, M. I.; CHAVES, S.; GONZALEZ, M.V.; RACEDO, J.
Lugar:
Tucuman
Reunión:
Congreso; XXX International Society of Sugarcane Technologists Congress; 2019
Institución organizadora:
ISSCT
Resumen:
Brown rust, caused by the fungus Puccinia melanocephala, is a severe foliar disease widespread across sugarcane-producing areas. The use of resistant cultivars is the main control strategy. Given the complex genome of sugarcane, the discovery of Bru1, a major gene conferring resistance to brown rust, represented a turning point in sugarcane genetics and breeding. The availability of diagnostic markers for Bru1 allowed determination of the distribution of this resistance source, highlighting the need of broaden the genetic basis for disease resistance. We aimed to identify DNA markers associated to brown rust resistance source(s) different from those conferred by Bru1. F1 progeny derived from a cross between TUC 00-36 and RA 87-3, highly susceptible and highly resistant to brown rust without Bru1 gene, respectively, was evaluated in field trials in order to select the most highly susceptible and highly resistant genotypes. Thirty clones from each class were selected to compose the ?pooled-tails? (PT) mapping population, which was planted in a new trial with two replicates and evaluated for brown rust reaction during two additional crop seasons. Whole-genome profiling of the PT mapping population and their parents were obtained by DArTSeq technology. Field evaluations across crop cycles confirmed 30 individuals rated as resistant and 24 as highly susceptible. Six genotypes were rated as intermediate, showing 3 or 4 in the severity scale, and then were removed for the later analysis. From DArTSeq, 23,299 SNPs were obtained. Thirty-seven associations between markers and brown rust resistance were found. These markers could be a valuable tool for breeding since they will allow to select resistant genotypes, even in absence of the disease, and pyramiding different genes into a single genotype enhancing the durability of the resistance.