SELECTING DAYS TO FLOWERING IN LENTIL (Lens culinaris Medik.) FOR A NORTHERN TEMPERATE CLIMATE
Lentil varieties in western Canada are continuously improved to stay relevant as a crop. This improvement requires access to a diverse pool of genetics, of which in lentil, is difficult to use due to a lack of adaptation to our environment. Genetic markers for days to flowering (DTF), have been identified but have not yet been tested in western Canadian lentil breeding. Phenotyping DTF in Saskatchewan field experiments and mapping, using markers associated with specific loci in the lentil genome, was used to identify loci relevant to western Canadian conditions and applicable to diverse lentil germplasm. A bi-parental RIL population (LR-11) created using a Canadian line (CDC Milestone) crossed with a Bangladeshi line (ILL 8006) was phenotyped for multiple phenological traits in Saskatchewan field experiments over four site-years. A linkage map consisting of six linkage groups (LGs) was constructed using 11, 558 single nucleotide polymorphism (SNP) markers. Four quantitative trait loci (QTL) for DTF (q.DTF) were identified in more than one site-year. Of these, the two which explained the largest amount of the observed phenotypic variability each contained members of the Flowering Locus T (FT) gene family as annotated in the lentil reference genome. An exploratory expression study of these FT genes provided additional support that q.DTF.6-1 and q.DTF.6-2, may represent variation at LcFTb2 and LcFTa1, respectively. A diversity panel, AGILE-LDP, was screened with a marker representative of each of these two q.DTF and both markers accounted for differences in DTF in Saskatchewan. The inheritance patterns of the two markers, and the implied roles of LcFTb2 and LcFTa1 based on research in related legumes, provided support that the markers are accounting for at least some of the relevant variation in DTF in this panel. These q.DTF could be used to improve selection of preferred allele combinations across diverse material. This study emphasized the need for further investigation into the underlying genes and molecular pathways implicated by q.DTF in any study, and that, on their own, focusing on any one locus leaves many unanswered questions and reduces marker adoption by breeders. In addition to DTF, days to emergence, vegetative period, and reproductive period were identified as having potential for identifying additional discrete, and phenologically relevant genomic regions that should be followed up in future studies.
lentil, qtl, days to flower, development
Master of Science (M.Sc.)