The Molecular Markers For Resistant Gene Of The Important Wheat Cultivar-Xiaoyan 6 To Wheat Stripe Rust (Puccinia Striiformis West.)

Xiaoayan 6 is the famous variety developed by China using foreign genes in 80's of last century. It has been grown over 20 years with its high quality, resistant disease and resistant adversity, and has become one of six cultivars whose planting size exceeds hundred million mu. Due to its specific merits, the scientists focus on it and study it from different respect. In the mechanisms of resistant yellow rust, Xiaoyan 6 has been studied from such aspect as biology, pathology, biochemistry, and is thought to posses high-temperature resistance belonging to non-specific endurable resistance.This article studied the inheritance mechanisms of this cultivar from classical and molecular genetics, which will offer the selective markers for marker assisted selection. The results were obtained as follows:1. The study make clear the genetic mechanisms of resistant yellow rust genes, and find xiaoyan 6 expresses different patterns in common temperature and high temperature. Xiaoyan 6, the resistant gene against yellow rust originating from Elytrigia elongate. Four races were used to postulate the resistant inheritance rules in common temperature (15-17℃) and high temperature (20-22℃) by means of F2 population from the cross of xiaoyan 6 and mingxian 169. In common temperature, xiaoyan 6 has one gene resisting four races (CY29-mut3, CY-28, CY-27, and CY-25). In high temperature, high temperature resistance maybe correlate with cytoplasmic inheritance.There are two dominate genes against CY29-mut3, one belonging to nuclear inherience, one belonging to cytoplasmic inherience, two dominate genes and one recessive gene controlling the resistance against CY-28 and CY-25,one dominate gene belonging to nuclear inherience, one dominate gene and one recessive gene belonging to cytoplasmic inherience .2. The standard RAPD system was developed and the molecular markers linked to the interest gene were identified. Of the 220 random primers, 13 primers can showpolymorphisms between the parents and two bulks. At last, two markers were determined, OPT17700 and OPC111000- The rate of recombination is 7.9%,8.6%, respectively, in coupling, and the distance between the marker and the interest gene are 8.6 cM, 5.16cM, 9.9cM> 8.69 cM?In order to transfer RAPD marker to SCAR marker, the DNA fragment was purified and cloned using pBluescript KS vector, which was sequenced. Also, OPC111000 was verified in xiaoyan 22 .This research provide molecular marker for the cultivars coming from Elytrigia elongate, which can test those cultivars posses the same gene and supply the ways for MAS and pyramiding genes..