Breeding Of Blast Resistance Genes D12 And R6 In Rice Kongyu131

Rice?Oryza sativa L.?,one of the world's three major crops,is regard as staple food by over half people in the world.More than 60%Chinese consider rice as staple food,China is the world's largest rice producer and consumer.Heilongjiang province is Chinese major grain production,in 2015,grain planting area is stable at 200 million mu,among them,rice area is more than 60 million mu,it's the first in China.Rice Kongyu131?Oryza sativa L.subsp.Japonica?is widely planted in Heilongjiang Province.Kongyu131 has good character and quality,it quickly makes Kongyu131 major cultivars in the province of Heilongjiang in the past few years that short growth period,high yield advantage,especially strong cold tolerance,but Kongyu131 did not contain valid Kongyu131 blast resistance gene,rice blast in practice often extensively reduce production,it severely limits safe production,including Kongyu131 and many other varieties.Practice has proved that the most effective means of blast prevention and treatment is to cultivate rice blast resistant varieties.Therefore,this research used varieties D12 and R6 containing effective rice blast resistance gene as d12 and r6 donor parents,blast resistance variety Kongyu131 was cultivated by using MAS breeding techniques to solve the problem of blast limiting Kongyu131 safety production.The main results of the study are as follows:1.40 rice blast fungus spore single strains were isolated from the rice blast sample,which were collected from all regions of Heilongjiang province,the sample's main host is Kongyu131.5 strong pathogenic strains of rice blast fungus single spore were screened by pathogenicity test.2.Blast resistance of donor parents D12 and R6 was identified by using 5 screened rice blast fungus single spore strains.Results showed that the donor parents D12 and R6performed high resistance to rice blast fungus flora main on Kongyu131,Which can improve rice blast resistance genes for Kongyu131 in cold area.3.The establishment of Molecular Identification system of Kongyu131 blast resistance gene d12 introgression lines:SSR markers RM27792 was foreground selection markers,SSR markers RM27654 and RM28255 were left side?top?and right side?bottom?exchange markers,51 polymorphic markers were screened from 210 SSR markers as background selectable markers.4.The establishment of Molecular Identification system of Kongyu131 blast resistance gene r6 introgression lines:SSR markers RM19766 was foreground selection markers,SSR markers RM19960 and RM276 were left side?top?and right side?bottom?exchange markers,72 polymorphic markers were screened from 240 SSR markers as background selectable markers.5.Foreground selection,both sides of exchanged selection,background selection and resistance identification of field blast were done on introgression lines generation plants of Kongyu131 rice blast resistance gene d12.BC₆F₁ positive plants of carrying rice blast resistance gene d12,exchanged on the left exchange markers RM27654 and 100%genetic background recovery rate have been screened,they can be breeding materials for cultivating rice blast resistance Kongyu131?d12?.6.Foreground selection,both sides of exchanged selection,background selection and resistance identification of field blast were done on introgression lines generation plants of Kongyu131 rice blast resistance gene r6.BC₅F₁ positive plants of carrying rice blast resistance gene r6,exchanged on the left exchange markers RM19960 and 100%genetic background recovery rate have been screened,they can be breeding materials for cultivating rice blast resistance Kongyu131?r6?.7.BC₆F₁ positive plants of d12 introgression lines were identified by using national standard DNA fingerprinting of rice variety identification,comparing 6 strains of hybrid positive plants with control Kongyu131,there were no difference in 24 SSR markers,it meant the number of marked difference is zero,these plants can be judged to be"same variety or extremely similar varieties"according to the national standard.8.BC₅F₁ positive plants of r6 introgression lines were identified by using national standard DNA fingerprinting of rice variety identification,comparing 6 strains of hybrid positive plants with control Kongyu131,there was difference on?type marker RM72 of No.2 plant,these plants can be judged to be"similar varieties"according to the national standard?No.2 plant can not be candidate for subsequent backcross breeding?,there were no difference in 24 SSR markers of the other five positive plants,it meant the number of marked difference is zero,these plants can be judged to be"same variety or extremely similar varieties"according to the national standard.