QTL Comparative Analysis For Some Important Agronomic Traits Of Main Rice And Ratooning Rice To Utilize RILs Population

The most traits of crop are quantitative character controlled by more than one gene.It is very important for crop breeding to identify the quantitativetrait locus (QTL).This research used glutinous rice 89-1 as female parent,used Shuhui 527 as male parent,and got the F2 recombination inbred lines(RILs) population through the method of one seed reproduction,then plant them in 2007 suitable season,and inspected the plant height,the number of effective panicle,spike length and other six economical characters,then inspected the number of effective panicle,spike length, regeneration capacity and other five character in retooning rice.In additional,we also surveyed the germination percentage of rice and the cold-hardiness in the regeneration season.At the same time,we constructed the genetic map using SSR marker,and map the QTL character.The main results of the research as follow:1.All the inspected trait showed continuous variation,and approach to normal distribution in RILs population,which explained the characters all are quantitative trait.The analysis of variance showed all the gene difference between the economical characters was significance or extremely significance.This suggested the wide range genetic variation between the RILs population2.The correlation analysis of all inspected characters showed many characters are correlative.In the positive season,the plant height,economic panicle and the spike density were significant positive association,the plant height,spike length,the total number of every panicle,and the economical number of very spike were extremely significant positive association.The spike density,the total number of every panicle,and the economical number of every panicle,were extremely significant positive association.The number of productive spike,spike length and the total number of every panicle were extremely significant positive association.The economical number of every number setting percentage was extremely significant positive association.The kilo-grain weight and spike density were extremely significant negative association.The full panicle stage and the spike length were significant negative association.The full panicle stage,total number of every panicle, spike density and the economical number of every panicle,were extremely significant negative association.In the regeneration season,the capacity of regeneration,the total number of every panicle,spike density was extremely significant positive association. The setting percentage and the kilo-grains weight were significant positive association. Panicle lengths,the total number of every panicle and the spike density were extremely significant positive association.The total number of every panicle,the economical number and the spike density were extremely significant positive association.3.We analyzed the polymorphism of parents using SSR primers.There are 118 pair primers presenting polymorphism between parents.We detected 169 strains using these primers,and then we constructed a genetic linkage map that containing 105 molecule markers and 12 linkage groups.This map covers 1144.1 cM of rice genome and the average length between markers is 10.90cM.All above results come from the least squared method of composite interval mapping(CIM).4.Analyzing QTLs of corresponding traits,all detected traits can find QTLs. There are 27 QTLs distributing 1,2,3,5,6,7,8 and 10 chromosomes that detected in the positive season.In retooning season,27 QTL were still detected that distributing 1,2,3,4,5,6,7 and 10 chromosomes.Comparing two seasons' results,there are 11 QTLs distributing 1,2,6,7 and 10 chromosomes corresponding 7 traits such as Panicle length(qP16),total number of every panicle(qSnp1-1,qSnp1-2,qSnp6),spike density(qDp1-1,qDp1-2),kilo-grains weight(qKw2-1,qKw2-2,qKw2-3,qKw7-1, qKw10).Three other traits containing number of effective panicle,effective number of every panicle and maturing rate were not detected.In two seasons,because the recurrence rate of kilo-grains weight is highest,we think hereditary capacity of kilo-grains weight is very strong and is almost not affected by environment.At the same time,we firstly' detected two QTLs of regenerative capacity(qRa4, qRa5) respectively offering 8.17%and 7.09%of phenotypic variation.We also firstly detected two QTLs of cold resistance such as qCtb3 and qCtb5 regulating the cold resistance of rice shoot stage these respectively offer 75.57%and 79.04%of phenotypic variation,qCtr5 located the same marker with qCtb5 controlling cold resistance of overwintering rice stub.In addition,we detected a QTL of controlling percentage of germination(qGr10).5.This research indicated some QTLs of different traits can be located in the same locus or area.For example,a locus between RM259-RM220 in 1 chromosome can control total number of every panicle(qSnp1-1(R)) and spike density (qDp1-1(M)).In this area,a QTL of Panicle length(qP11-1(R)) was also detected.A locus between RM340-RM528 in 6 chromosome can control total number of every panicle,panicle length and height(qPh6-2(M),qP16(R),qSnp6(R)).A locus between RM346-RM351 in 7 chromosome can control effective number of every panicle and maturing rate(qGpp7(M),qSsr7(M)).These results these being from pleiotropism or close linkage of QTLs could induce a huge improvement of rice breeding.