Identification And Gene Mapping Of Resistance To Magnaporthe Grisea In Songjing No.9

Rice is one of the most important food crop.Rice blast caused by the Pyricularia oryzaeworldwidely, has a huge impact on rice yield and quality. The long-term practice has proved thatthe use of rice varieties resistance is an effective way to resist rice blast damage. HeilongjiangProvince is characteristiced by rice acreage, high yield and excellent grain quality, occupies a highposition in China’s grain production.The rice varieties which are in the process of long-termco-evolution with the rice blast, form a wide rice blast blast resistance spectrum and durableresistance characteristics. The research of Japonica rice in Heilongjiang on genetic regular of blastresistance and gene mapping of rice blasr resistance has an important practical significance.especially for Japonica rice blast resistance breeding.At the same time, due to the occurrence ofrice blast is the result of the interaction of the rice blast fungus and rice varieties, analysis of Blasttype, pathogenicity and distribution characteristics in the rice production areas can be moreconductive to genesexcavations of lasting resistance in local varieties and has more guidingsignificance for prevention of rice blast and reasonable distribution of disease-resistant varieties.In the study, the M. grisea of Heilongjiang Province in2011was isolated and identified, andthen reseaching the distribution of the blast pathogenic in Heilongjiang Province, while theanalysis spectrum of anti parental Songjing, No.9by using the identified physiological races. Theresistant parent Songjing9and ordinary variety LTH are hybridized and selfing to get F1and F2forbuilding gene mapping population. The parent and offspring are identificated in tillering by threerice blast fungus in order to reseach the inheritance of resistance and preliminary position ofresistance genes in Songjing9which lay the foundation for fine mapping, cloning, andpolymerization breeding. The results are as follows:1. The37Magnaporthe strains are isolated from the five regions of Heilongjiang Province byseven differential varieties and identified into23physiological races of6groups. ZC populationfrom6groups has the highest frequency (35.1%). ZC3rice gets the highest frequency (16.8%) in37physiological races. ZC population is the dominant population of rice blast HeilongjiangProvince; ZC3is the dominant specie in2011.2.23physiological races identified from some of the major rice production area inHeilongjiang Province have different virulence of the seven Chinese differential varieties. Theyshow strong virulence to Kanto51, Dongnong363andHejiang18which are japonica rice while lower influence to the three indica varieties.3. From the distribution of Magnaporthe populations in Heilongjiang Province, fivepopulations of physiological races are separated in Harbin and Hegang, and the dominant groupsare both ZC group; Jiamusi gets all the Magnaporthe populations, including ZC group is also thedominant group, the result shows rice blast physiological race is complex and representative inJiamusi. Among6strains in Fuyuan, ZB, ZC group have two strains and one strain in ZDgroup.The dominant specie is not obvious. ZA group is the dominant population in Mudanjiangregion. On the whole, rice blast populations more evenly distributed in Heilongjiang Province.4. The resistance spectrum analysis of Songjing9is91.9%which is identified by37strainsisolated; and the disease resistance frequency of dominant specie ZC3in Heilongjiang Province is83.3%. It shows higher resistance. In7identified strains from Japan, exceptdisease resistancefrequency of Dao168was lower (64.7%), the other six strains of disease-resistant frequency arebetween80%and100%. Above all, resistance spectrum of Songjing9is broad.It is a good varietyof rice blast resistance sources and has a good adaptability in Heilongjiang.5. The genetic analysis of Songjing9is made by three rice blast fungus-North1, Yan54-20and ZC3(dominant physiological races in Heilongjiang Province) for disease resistance genes. Theresult shows that resistance characteristics of Songjing9are controlled by a single dominantnuclear gene.6. By the method of RCA and BSA, The preliminary resistance gene of Songjing9toZC3islocated on chromosome1.Genetic distance with RM10494and RM10910are14.2cM and7.8cMrespectively.