Germplasm basis and QTL mapping for resistance to SCMV in chinese maize - Mexico, DF (Mexico) CIMMYT : 2004 - p. 27-34 - Printed
Sugarcane Mosaic Virus (SCMV) is an important disease of maize in China. Investigation of the germplasm basis and inheritance to SCMV resistance are important for germplasm improvement. During 1999 to 2001, the AMBIONET-China team analyzed the genetic diversity in 46 elite Chinese inbreds and provided a strategy of germplasm improvement for resistance to SCMV based on heterosis. Also, characterization of QTLs affecting resistance to SCMV and application of a marker-assisted selection (MAS) approach were undertaken using a linkage map with 89 SSR marker loci and the phenotypic data of F3 families derived from the cross Huangzao4 x Ye107. Three QTLs conferring resistance to SCMV were consistently identified on chromosomes 3, 6, and 10 in experiments carried out in 2000 and 2001, while two more QTLs on chromosomes 1 and 5 were found in 2001. The Huangzao4 contributed all the QTL alleles conferring resistance to SCMV. The largest QTL was consistently located on chromosome 3 across two years, which could explain 19.48% and 26.86% phenotypic variance, respectively. Both the QTLs on chromosomes 3 and 10 showed significant additive gene effects, while other QTLs on chromosomes 1, 5 and 6 displayed dominant, overdominant and partial dominant gene action, respectively. Based on this study, it was recommended that the MAS for SCMV resistance could consist of the use of QTLs on chromosomes 3, 1,6, and 10, combined with the conventional selection method.