Analysis Of Rice Blast Resistance Gene Pyramids At High Generation And The Overall Assessment Of Agronomic And Quality Traits

Rice is one of the most important food crops in the world.It is the staple food of more than half of the world’s population,but rice blast seriously threatens its yield and quality.Using marker-assisted selection to polymerize multiple blast resistance genes could improve the broad spectrum durable resistance.In order to clarify the genotypes,agronomic traits and rice quality of rice blast resistance gene polymeric high generation materials,according to the research results of 582 rice hybrid progenies,the parents of rice blast resistance and 43 high generation rice hybrid progenies were selected as experimental materials.Eight functional markers of blast resistance genes were used for molecular detection of blast resistance genes and genotypes were analyzed,and the main agronomic and quality traits were evaluated comprehensively.In order to provide reference for molecular breeding of rice blast resistance in Ningxia.The main results are as follows:1、Molecular detection and genotype analysis of blast resistance genes in parents and 43 high generation rice materials were carried out.The results showed that there were differences in the number and types of blast resistance genes carried by the tested materials.A total of 12 blast resistance gene pyramids were detected:Pi-ta+Pik-h,Pi-ta+Pik-h+Pi-b,Pi-ta+Pi-b+Pi-5,Pi-ta+Pik-h+Pi-b+Pi-5,Pi-ta+Pik-h+Pi-b+Pik-m,Pi-ta+Pi-b+Pik-m+Pi-5,Pi-ta+Pik-h+Pi-b+Pi-5+Pi-9,Pi-ta+Pik-h+Pi-b+Pik-m+Pi-9,Pi-ta+Pik-h+Pi-b+Pik-m+Pi-5,Pi-ta+Pik-h+Pi-b+Pi-d2+Pik-m,Pi-ta+Pik-h+Pi-b+Pik-m+Pi-5+Pi-9,and Pi-ta+Pik-h+Pi-b+Pi-d2+Pi-5+Pi-9。All the tested materials were polymerized with Pi-ta gene,but no Pi-2 gene was polymerized.2、Through the correlation analysis and principal component analysis of the agronomic traits of the parents and 43 rice blast resistance gene aggregates,the comprehensive evaluation was carried out.According to D value,the advantages and disadvantages of parents and 43 rice blast resistance gene polymerizations were sequenced.The D value of the tested materials ranged from 0.148 to 0.824,among which,the tested materials with D>0.538 were the top 10 high generation materials of blast resistance gene polymeric.They are NO.1(R21044),NO.2(R21025),NO.3(R21045),NO.4(R21016),NO.5(R21001),NO.6(R21003),NO.7(NJ43),NO.8(R21014),NO.9(R21013)and NO.10(R21020),these 10 test materials were regarded as the high generation of rice blast resistance gene polymeric materials with good agronomic traits screened out in this study.3、The correlation analysis and principal component analysis were carried out to evaluate the quality traits of the high generation rice materials from the parents and 43 rice blast resistance gene aggregates.The quality of parents and 43 rice blast resistance gene polymerizations were sequenced according to D value.The D value of the tested materials ranged from 0.222 to 0.740,among which,the tested materials with D>0.503 were the top 10 high generation materials of blast resistance gene polymeric.They are NO.1(R21045),NO.2(NJ43),NO.3(R21029),NO.4(R21028),NO.5(R21031),NO.6(R21015),NO.7(SHF47),NO.8(R21040),NO.9(R21016)and NO.10(R21020),these 10 test materials were regarded as the high generation of rice blast resistance gene polymeric materials with good quality screened out in this study.4、Through comprehensive analysis of blast resistance genotypes,agronomic traits and quality traits,the results showed that the genotypes of blast resistance high generation rice materials with good comprehensive traits contained resistance genes Pi-ta,Pik-h,Pi-b and Pi-5.Therefore,R21016,R21020,NJ43 and R21045 were high quality rice blast resistance gene polymeric materials.Meanwhile,Pi-ta+Pik-h+Pi-b+Pi-5 was the best blast resistance gene polymeric patter.