QTL for seed germination rate and related physiological traits of Brassica napus L.

Abstract

One hundred and eighty-three recombinant inbred lines from the cross between GH06 and P174 were used for genetic analysis of seed germination rate and physiological trait analysis of Brassica napus L. Composite interval mapping (CIM) was applied to identify QTL associated with seed germination rate (GR) of the seeds that stored for two years (STY), one year (SOY), and fresh seeds (FS), respectively. The activity of lipases, seed conductivity, reducing sugar content, total sugar content, and root vitality of STY and FS were investigated. The QTL for seed GR of various stored seeds were different. Three QTLs for STY were detected on the linkage group (LG) 9, 14, and 17. Two QTL for SOY were mined on LG 5 and 9. Two QTLs for FS were detected on LG 4 and 18. The germination rate of seeds from three years was significantly different, and the QTL of GR was not identical, which indicated that the seed germination was controlled by many loci. Furthermore, the seed germination rate was negatively correlated with seed conductivity, which means that measurement of seed conductivity can be used to estimate GR, and the study of conductivity is important for GR research.