Quantitative trait loci for photosynthetic pigment concentration in a doubled-haploid population of Pak Choi (Brassica rapa ssp. chinensis var. communis Tsen et Lee).

摘要

Quantitative trait loci (QTL) mapping and marker development are essential steps in any molecular breeding programme. In this study, QTL for photosynthetic pigment concentration were identified using a doubled-haploid (DH) population of 112 lines derived from an F₁ hybrid of Pak Choi, 'Shulv', obtained from a cross between Brassica rapa lines SW-13 and SU-124 through microspore culture. QTL mapping was carried out using a modification to the map of 'Shulv'. Alignment of the linkage groups was carried out with those of reference B. rapa maps, allowing the assignment of these groups as A01-A10. In total, 11 QTL were associated with photosynthetic pigment concentration and identified on linkage groups A05, A08, and A10. The maximum phenotypic variance for a single QTL was 38.0%. Markers closely linked to these QTL could assist in the development of Pak Choi cultivars with increased yield, due to having improved photosynthetic capabilities.