| Wheat stripe rust is a kind of worldwide disease which seriously damage to wheat production, caused by Puccinia striiformis West. f. sp. Tritici. China is the largest independent epidemic region of wheat stripe rust in the world. Planted resistance varieties is the most effective and economic measure to prevent and control wheat stripe rust. However, due to the highly variability of wheat stripe rust, it is easy to evolve new pathogenic physiology races. And the resistance source of wheat varieties structure in our country is single, which lead to many wheat varieties loss their disease resistance. Since the 1950s, wheat stripe rust pandemics have occurred many times in our country that caused great loss every time. Therefore, discover new resistance genes, aggregate multiple resistance genes into an organic whole, develop a lasting disease-resistant wheat varieties, and rich diversity of resistant wheat varieties are becoming a hot research topic in today’s wheat breeders.Sichuan belong to stripe rust epidemic areas where yellow rust live through the winter. Sichuan wheat landraces adapt to the Sichuan ecological environment, and have many other advantages, such as more flowers, more grains, high affinity, and high disease-resistance. So Sichuan wheat landraces have great value to use. This research selected Sichuan wheat landrace Hejiang yuzai wheat which has high resistance to yellow rust and susceptible variety Taichung29 to hybrid and produce a series of offspring material. Through inoculated representative yellow rust physiological races analysis resistance genetic of Hejiang yuzai wheat at the field and greenhouse environments. And using four kinds of molecular marker technology combined with Chinese Spring nulli-tetrasomic lines to develop linked molecular marker and located chromosomal location of yellow rust resistance gene of Hejiang yuzai wheat. The main results are shown as following:1. Inoculated mixed pathogenic physiology races at seedling stage in greenhouse and adult stage in field to identificated that Sichuan landrace wheat Hejiang yuzai wheat has nearly immune yellow rust resistance; Genetic analysis of F1, F2 and F2:3 hybrid generation of Hejiang yuzai wheat and Taichung29 showed that the yellow rust resistance of Hejiang yuzai wheat is controlled by a pair of main effect dominant gene, temporarily named YrHY.2. Using RGAP, TRAP, SRAP and SSR 4 molecular marker technologies analyzed F2 hybrid generation of Hejiang yuzai wheat and Taichung29.22 linked molecular markers were found, including 8 RGAP molecular markers (Ptokin2/S1-INV, Ptokin2/Pto-kin2IN, Ptokinl/Ptokin2, Ptokinl/XLRR-INVl, Ptokinl/Pto-kin2IN, AS1/Cre3-k3, NLRRrev/Pto-kinl and INAS1/Cre3LR-F),2 TRAP molecular markers(FIX5/Oddl5-700 and FIX4/Ga5-800),6 SRAP molecular markers (F-mel/R-mel7, F-me7/R-me18, F-me5/R-me9, F-me11/R-me9, F-me14/R-me4 and F-me12/R-me18),6 SSR molecular markers (Xwmc438, Xcfd66, Xwmc463, Xgpw5211, Xbarc92 and Xgdm130). Combined with the specificity of the SSR markers position on chromosome and Chinese Spring nulli-tetrasomic lines, the main effect of dominant of yellow rust resistance genes YrHY was positioned on the 7DS.3. Calculated genetic distance among markers with gene through software QTL IciMapping V3.3, and genetic map used software Mapdraw V2.1 to draw. The order of 22 markers in the genetic map is NLRRrev/Pto-kin11N, AS1/Cre3LR-F, FIX4/Ga5-800, Xwmc463, Xwmc438, Xbarc92, Xcfd66, F-me12/R-me18, Ptokin2/S1-INV, Ptokin2/Pto-kin2IN, Xgpw5211, Xgdm130, AS1/Cre3-k3, FIX5/Oddl5-700, Ptokinl/Pto-kin2IN, Ptokinl/XLRR-INVl, F-me5/R-me9, F-me14/R-me4, F-me11/R-me9, Ptokinl/Ptokin2, F-me7/R-me18 and F-mel/R-mel7. The closest flanking makers were Xbarc92 and Xcfd66 with the genetic distances of 4.3 cM and 8.5 cM, respectively.4. Gene YrHY differs from any other known Yr resistance genes on 7DS (Yrl8, Yr33, YrY201, YrY212, YrM8003 and YrWV) from pedigree, resistance level and comparing genetic distance of common markers, and is probably a novel gene. |
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