The development and validation of new DNA markers linked to the thousand-grain weight QTL in bread wheat (Triticum aestivum L.)

Abstract

Thousand-grain weight (TGW) is an important trait affecting wheat production. We previously identified a major quantitative trait loci (QTL) controlling the TGW on the 2D chromosome of wheat using a recombinant inbred line (RIL) population constructed by the cross between Tibetan semi-wild wheat Q1028 (Q1028) and Zhengmai 9023 (ZM9023). The positive allele at this QTL is from ZM9023. To further characterise this QTL, here, we try to develop and validate the high-resolution melting (HRM) and sequence-characterised amplified region (SCAR) markers. One HRM marker (0C98-411) and two SCAR markers (E301-700 and B0BB-10470) were developed and integrated into the genetic map. All of these three markers were validated in three populations with different genetic backgrounds. 0C98-411 is the most closely linked marker that could trace QTgw.sau-2D in molecular marker assisted breeding.