Genetic analysis of falling number in three bi-parental common winter wheat populations

The objective of the present study was to analyse the genetic basis of falling number in three winter wheat populations. Samples for falling number determination for each population originated from at least three test environments that were free from the occurrence of preharvest sprouting at harvest time. Quantitative trait locus (QTL) analysis employing falling number values from single environments identified eight, five and three QTL in the populations Dream/Lynx, Bussard/W332-84 and BAUB469511/Format, respectively. A major QTL common to all three populations and consistently detected in each environment mapped to the long arm of chromosome 7B. The QTL was located to a similar genomic region as the previously described major QTL for high-isoelectric point α-amylase content. The T1BL.1RS wheat-rye translocation and the dwarfing gene Rht-D1 segregating in Dream/Lynx and BAUB469511/Format were found to be important factors of falling number variation. In both populations, the presence of Rht-D1b or the absence of T1BL.1RS increased falling number. The results indicate that late maturity α-amylase, responsible for low falling numbers, has now been documented in German wheat germplasm.