Quantitative Trait loci (QTL) Identification for Resistance to Mal de Rio Cuarto Virus (MRCV) in Maize Based on Segregate Population.

ROSSI, EZEQUIEL A.; BORGHI, MARÍA L.; DI RENZO MIGUEL A.; BONAMICO NATALIA C.

The Open Agriculture Journal

Bentham Science Publishers Ltd

Lugar: Sharjah; Año: 2015 vol. 9 p. 48 - 55

Mal de Río Cuarto virus (MRCV) is one of the most devastating pathogens in maize (Zea mays L.) causing seriousyield loss in susceptible cultivars in Argentina. An effective solution to control the virus is to use resistant genes toimprove the behavior of susceptible genotypes. The goals of this work are to identify simple sequence repeats (SSR)linked to quantitative trait loci (QTL), for resistance to MRCV, and to validate QTL found in previous research with differentgenetic backgrounds. Two hundred and eight F2:3 families derived from a cross between a susceptible inbred line,B73, and a resistant inbred line, LP116, were evaluated across three environments in the disease-endemic region. Diseaseincidence (INC), disease severity (SEV) and disease severity index (DSI) were employed to evaluate F2:3 families. Basedon this segregant population, ninety-eight simple sequence repeat (SSR) markers selected from 173 markers were used.The means of all measured traits followed near-normal distribution; therefore these traits may be considered as quantitativelyinherited characters. For INC, SEV and DSI all estimates showed a moderate heritability ranging from 0,33 to 0,72.Some quantitative trait loci (QTL), each explaining around 10% of phenotypic variance were found on chromosome 1, 6,8 and 10. The identification of QTL conferring resistance to MRCV may contribute to breeding programs seeking to protectthe crop through improved genetic resistance.