The Mapping Of QTL Controlling Agronomic Traits And Glume Hairiness Gene (Hg) In Tibet Semi-wild Wheat

Tibetan semi-wild wheat (Triticum aestivum ssp. tibetanum Shao) is a primitive hexaploid wheat resource distributed only in Tibet. It is characterized by unique characteristics such as tolerance to nutrition deficiency and strong seed dormancy with great potential being exploited in wheat breeding program. To fully tap the advantages of Tibetan semi-wild wheat in wheat breeding, we investigated nine main agronomic 9 traits in 186 recombinant inbred lines (RIL) from a cross between Tibetan semi-wild wheat Q1028 and common wheat Zhengmai 9023 (ZM9023). The F9-F12 of the RIL and two types of molecular markers (SSR and DArT) were used in this study. In addition, the RIL also be used to locate the glume hairiness gene Hg. In order to increase the density of molecular marker,5 SSR marker were developed in this study, and a F8 RIL derived from Q1028×99E18 (cultivar identifition) was used to test the stability of SSR. The result of this study as follows:1. The RIL population derived from Q1028 x Zhengmai9023 was used to detect QTL for 9 agronomic traits including heading date, anthesis, plant height, tiller number, spike lenth, spikelet number per spike, spike density, grain weight per spike and 1000 grain weight on whole genome. A total of 45 QTLs were detected on 12 chromosomes include 1A (2),2A (1),2B (5),2D (10),3A (2),3D (3),4A (1),5A (8),5B (4),6A (1), 6B (3) and 7A (5), those QTLs can explain 4.69-29.71% of the phenotypic variation. Positive alleles of more than half (28) of these QTLs were derived from Q1028. Of these QTLs,25 (56%) were detected in at least two growing seasons. Fifteen stable QTLs, which were significant across all three growing seasons, were identified.2.11 QTL clusters were got on 7 chromosomes including 1 A,2B,2D,3D,5A,5B and 7 A, each of the cluster contains 2 to 5 QTLs, involves 8 agronomic traits, such as heading date, anthesis, plant height, spike length, spikelet number per spike, spike density, grain weight per spike and 1000 grain weight.3. In order to get a exact map of Hg gene,5 new SSR markers (saufc2, saufc9, saufcl7, saufc25 and saufc90) were developed on chromosome 1 AS. Hg gene was located in a 3.3 cM of Xsaufc2-wPt-734000. Especially, the genetic distance between Hg and Xsaufc2 only 1.6 cM. To validate the effectiveness of the five SSR markers, another RIL population derived from Q1028×99E18 was applied. The five markers could construct a linkage map with Hg gene, it was located in the region between Xsaufc17 and Xsaufc90.