2019 Volume 21 Issue 2 Pages 115-123
To identify quantitative trait loci (QTL) that confer excellent resistance to pre-harvest sprouting (PHS) in wheat, levels of sprouting in matured spikes and grain dormancy were investigated in a population of doubled haploid lines derived from a cross between the breeding line “Kitakei 1802” (highly tolerant to PHS) and the local leading variety “Kitahonami”. The doubled haploid population and parental genotypes were grown in six different environments. As sprouting resistance and grain dormancy were gradually lost after maturity, spikes were collected 10 days after physiological maturity. Assessment for PHS resistance was based on a sprouting assay conducted during 7–10 days artificial rain treatment on intact spikes, whereas grain dormancy was evaluated in germination tests at 15°C. Four QTL in total were detected in the sprouting assay. A QTL on chromosome 2D, designated as QPhs-2D, was found to be a stable QTL with a large effect across all six environments. The effect of the MOTHER OF FT AND TFL1 (MFT-3A) gene was detected in three environments. The remaining two QTL with minor effects were identified on chromosomes 1A and 7B in single environments. The resistant alleles at these QTL were all derived from “Kitakei 1802”. The effect of MFT-3A on grain dormancy was evident whereas the effect of QPhs-2D was unclear. These results demonstrated that incorporating QPhs-2D for sprouting tolerance along with MFT-3A for grain dormancy could markedly contribute to excellent PHS resistance.
