Soil-borne cereal mosaic (SBCM) is a viral disease which affects wheat in Europe. In durum wheat, the cultivated germplasm shows responses ranging from susceptibility to almost complete resistance. Genetic analysis of SBCMV resistance was carried out using two recombinant inbred line (RIL) populations of 180 lines each, obtained from the crosses Meridiano (resistant) × Claudio (moderately susceptible) and Simeto (susceptible) × Levante (resistant). The RILs were characterized for SBCMV response (symptom severity scores and virus concentration in leaves) in the field in 2007, 2008 and 2009 under severe and uniform SBCMV infections and were genotyped with SSR and DArT® markers. Transgressive segregation was observed for the disease response traits, with high heritability values, consistently > 80%. A major QTL (QSbm.ubo-2BS) in the distal chromosome 2BS region was identified in both populations; it accounted for 60-85% of the phenotypic variation for symptom severity, 40-55% for virus concentration and 15-30% for grain yield. The meta-QTL analysis carried out using the entire dataset suggested that in both populations SBCMV resistance is likely to be controlled by the same QTL, with the favorable allele being contributed by Meridiano and Levante. Our results confine QSbm.ubo-2BS in a ca. 2 cM-wide interval flanked by SSR markers that are being used for marker-assisted selection. Several QTLs with minor effects were also detected. The presence of QSbm.ubo-2BS was validated in a panel of 111 cultivated durum wheat accessions. The reported results open the possibility to further characterize QSbm.ubo-2BS and suggest its feasibility for a positional cloning approach.
Genetic control of resistance to s-borne cereal mosaic virus (SBCMV) in durum wheat. Atti XV Congresso SiPAV, Bologna, p.81
MACCAFERRI, MARCO;RATTI, CLAUDIO;RUBIES AUTONELL, CONCEPCION;STEFANELLI, SANDRA;TUBEROSA, ROBERTO
;
2011
Abstract
Soil-borne cereal mosaic (SBCM) is a viral disease which affects wheat in Europe. In durum wheat, the cultivated germplasm shows responses ranging from susceptibility to almost complete resistance. Genetic analysis of SBCMV resistance was carried out using two recombinant inbred line (RIL) populations of 180 lines each, obtained from the crosses Meridiano (resistant) × Claudio (moderately susceptible) and Simeto (susceptible) × Levante (resistant). The RILs were characterized for SBCMV response (symptom severity scores and virus concentration in leaves) in the field in 2007, 2008 and 2009 under severe and uniform SBCMV infections and were genotyped with SSR and DArT® markers. Transgressive segregation was observed for the disease response traits, with high heritability values, consistently > 80%. A major QTL (QSbm.ubo-2BS) in the distal chromosome 2BS region was identified in both populations; it accounted for 60-85% of the phenotypic variation for symptom severity, 40-55% for virus concentration and 15-30% for grain yield. The meta-QTL analysis carried out using the entire dataset suggested that in both populations SBCMV resistance is likely to be controlled by the same QTL, with the favorable allele being contributed by Meridiano and Levante. Our results confine QSbm.ubo-2BS in a ca. 2 cM-wide interval flanked by SSR markers that are being used for marker-assisted selection. Several QTLs with minor effects were also detected. The presence of QSbm.ubo-2BS was validated in a panel of 111 cultivated durum wheat accessions. The reported results open the possibility to further characterize QSbm.ubo-2BS and suggest its feasibility for a positional cloning approach.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
