Evaluation Of The Utilization Of Three Panicle Related Genes In Indica Hybrid Rice

In this study,female was indica curved panicle type sterile line ChuannonglA and erect panicle type and curved panicle type sterile line which were used in Chuannongl A were constructed.Male was the heavy panicle restorer line Shuhui498 of indica rice and its chromosome segment substitution line E463 and E559 containing Gn1a,chromosome segment substitution line R534 containing ipal,chromosome segment substitution line QR285 containing depl and Chenghui3203 as male.The sterile lines and restorer lines were divided into 42 groups according to 7×6 incomplete diallel crosses.On the basis of an analysis of panicle type related gene,study the relationship between yield and the main agronomic traits,plant characteristics and heterosis of different panicle type varieties,to evaluate the utilization value and potential of erect panicle type varieties in Indica Hybrid Rice.Results are as follows:1 Identification and analysis of genes of important panicle type showed that erect panicle type sterile lines F62A,F64A and F66A were depl genotype,curved panicle type sterile lines F61A,F63A,F65A and ChuannonglA were DEP1 genotype,curved panicle type and erect panicle type sterile line were functional Gn1a and IPA1 genotype;erect panicle restorer line QR285 was depl genotype;E463,E559,R534,Chenghui3203 and Shuhui498 were DEPI genotype.E463,E559 and Chenghui3203 were Gn1a genotype;R534,QR285,and Shuhui498 were gnla genotype;R534 was ipal genotype;E463,E559,QR285,Chenghui3203 and Shuhui498 were IPA1 genotype.2 The analysis of genetic background of different panicle type parents showed that the genetic difference was small in addition to the target gene.The similarity of F61A and F62A,F63A and F64A,F65A and F66A were respectively 93.7%,98.4%,68.9%,the difference between F63A and F64A was the smallest and the difference between F65A and F66A was the biggest.The similarity of E463,E559,R534,QR285 and Shuhui498 were respectively 74.3%,69.1%,95.0%,86.9%,the difference between E559 and Shuhui498 was the biggest.3 The phenotypic analysis showed that panicle neck curvature of erect panicle type parent was significantly less than that of curved panicle type parent.In the case of small genetic differences,plant height,panicle length,1000-grain weight,grain number per panicle,grain weight per panicle and yield per plant of erect panicle type sterile line containing DEP1 was significantly lower than that of curved panicle type sterile line,graindensity is opposite;top-three leaf length of erect panicle type sterile line significantly shortened,top-three leaf width increased significantly;stem diameter,section modulus,bending moment at breaking of erect panicle type sterile line decreased significantly.Compared with Shuhui498,E463 and E559:plant height,panicle length,1000-grain weight,grain number per panicle,grain density and grain weight per panicle were significantly decreased,effective panicle increased significantly,and the phenotype of E463 and Chenghui3203 closer together;the length and width of leaf were significantly decreased,leaf angle increased,the stem bar fine,bending moment at breaking decreased significantly.QR285:plant height,panicle length,1000-grain weight,seed setting rate and grain weight per panicle were significantly decreased,grain number per panicle and grain density were increased significantly;leaf length decreased significantly,leaf width were increased significantly.R534:plant height,grain number per panicle,grain density and grain weight per panicle were significantly increased,effective panicle number,seed setting rate and yield per plant decreased significantly;leaf length and width were decreased,except the flag leaf,reached significant level;stems became thick,bending stress was decreased,bending moment at breaking was increased,reached significant level.4 The analysis of yield of genotype combinations showed that yield of the curved panicle genotype combination DDGgII was higher(651.18kg/mu),followed by semi-erect panicle genotype combination DdGgII and erect panicle genotype combination ddGgII.The analysis of the main agronomic traits,leaf and stem traits showed that DdGgIi that grains per panicle,grain density and grain weight per panicle were higher,and had lower plant height and thicker stems,lodging resistance was better,but effective panicle number was less,yield was low.Therefore,for the ecological environment of Sichuan basin,the genotype combination DdGgII may be semi-erect panicle combination with better panicle traits.5 Identification and analysis of Heterosis of yield and main agronomic characters showed that GCA of grain number per panicle,grain density and top-three leaf width of erect panicle type sterile line were higher than that of curved panicle type sterile line,and the other traits were lower than that curved panicle type sterile line.GCA of effective panicle number was higher in E463;GCA of plant height,grain number per panicle,grain density,grain weight per panicle,top-three leaf width and bending moment at breaking were highest,GCA of effective panicle and yield were lower in R534;GCA of leaf width were highest,GCA of 1000-grain weight,panicle Length,top-three leaf length and leaf angle were lowest in QR285.Analysis of special combining ability showed that although the erect panicle type rice yield of GCA was relatively low,but could be widely bred with semi-erect panicle type hybrid rice with high SCA,such as semi-erect panicle type combinations F66A/E463,F62A/Chenghui3203,F62A/Shuhui498 had higher SCA in yield,and better heterosis potential.