Resistance of early-maturing European maize germplasm to sugarcane mosaic virus (SCMV) and maize dwarf mosaic virus (MDMV)

Sugarcane mosaic virus (SCMV) and maize dwarf mosaic virus (MDMV) are the most important viruses of maize in Europe. In field and greenhouse experiments, 122 early-maturing European maize inbreds (45 flint and 77 dent lines) were evaluated for their reaction to artificial inoculation by SCMV and MDMV. Three dent inbreds (D21, D32, FAP1360 A) with complete resistance and four dent inbreds (D06, D09, R2306, FAP1396A) with partial resistance against both potyviruses under both greenhouse and field conditions were identified. All other inbreds were highly susceptible to both SCMV and MDMV. Selection for virus resistance in maize breeding could be performed with only one virus at a time because all inbreds resistant to SCMV were also resistant to MDMV. Rank correlations between percentages of infected plants in greenhouse and field trials ranged from 0.51 to 0.72 for both SCMV and MDMV, suggesting that prescreening of breeding materials for virus resistance can be performed in the greenhouse but final evaluation in multilocation trials in the field is recommended.