QTL Analysis Of Rice Plant Type-Related Traits Based On RIL Population

Plant type improvement has always been the key to improving rice yield potential.Elucidating the genetic mechanism of plant type formation at the molecular level and exploiting and utilizing new plant type related gene /QTL can further enrich the theory of molecular breeding and accelerate the breeding process.In view of this,in this paper,a recombinant inbred line(RIL)population derived from the hybridization of indica rice IR36(male)and japonica rice J07-23(female)was used as the experimental material,and QTL mapping and analysis of plant type and panicle related traits were carried out through two-year repeated tests.The main test results are as follows: 1.In the past 2 years,the investigation and analysis of 21 related traits such as plant type and panicle of the RIL population showed that most of the traits were bidirectional superphilic separation in the RIL population,which was close to normal distribution.2.A total of 210 pairs of primers with polymorphism between parents were screened and the molecular genetic linkage map of J07-23 /IR36 recombinant inbred lines was constructed.The map covered 1505 cM of rice genome and the average distance of markers was 7.17 cM.3.The QTLs of 10 plant type related traits such as plant height,effective panicle number and blade length were analyzed,and 62 QTLs were located in chromosome 1,2,3,4,5,6,7,8,11 and 12 in two years,with the variation range of contribution rate of 4.21% to 30.29%.Among them,there are 6 primary QTL sites,namely qPH8b,qEPP4b,qEPP12,qFLW1a,qFLW1b and qFLA4.Ten QTLs were identified in two years,and the main effect QTL-qFLA4 was stably expressed in two years,with contribution rates of 15.38% and 16.97%,respectively.The QTLs associated with effective panicle number and inverted second leaf length were not duplicated in two years.4.In J07-23 / IR36 recombinant inbred lines,the QTLs of plant type related traits were distributed in clusters on chromosomes,and 5 QTL clusters were found on chromosomes 1,4,6 and 8.Seven QTLs(qFLW1a,qFLA1,qSLW1a,qFLW1b,qFLWR1,qSLW1b and qSLA1)were found to control leaf traits at the interval of RM6902-RM600 on chromosome 1.At the interval of RM1198-RM6321,5 QTLs of plant height and leaf traits were detected(qPH1,qFLL1,qSLL1,qSLW1b and qSLWR1).At the interval of RM3839-RM273 on chromosome 4,6 effective panicle numbers and leaf traits were detected(qEPP4a,qFLW4a,qFLW4b,qFLA4,qSLL4 and qSLA4).Four leaf QTLs(qFLW6,qFLA6,qSLL6b and qSLA6b)were detected on chromosome 6,RM6734-6-112.Six QTLs(qPH8a,qPH8b,qFLL8,qFLWR8,qSLL8 and qSLWR8)of plant height and leaf traits were detected in the 8-6.41-RM3395 range of chromosome 8.5.Of spike length,spike weight,branch number 11 panicle related properties such as QTL analysis,two years to 74 QTLs,distribution in 1,2,4,5,6,8,9,10,11 and 12 on the chromosome,the contribution rate of phenotypic variation range of 4.28% to 43.30%,the main effect of nine,respectively is qSBN2,qSBN2,qSN1b,qBN2a,qBN8,qBN12,qSSR2b,qSSR8b,qSSR12 and qGD1b.Eleven QTLs were identified during the two years,and qSN1b located on chromosome 1,was detected as the primary QTL only in 2019,possibly due to environmental impacts.In addition,several new sites were found,namely qSBN3b,qPBN6,qGN10 and qGD3c.6.Panicle related traits showed obvious cluster distribution on chromosomes 1,2,3 and 4,11 panicle traits(qPW1a,qPW1b,qSBN1a,qSBN1b,qSN1a,qGN1a,qBN1,qFGW1a,qGD1a,qSN1b and qGD1b)were located at the interval of RM1254-RM259 on chromosome 1.In the interval of RM5501-RM1198,5 panicle traits were identified(qPW1c,qSN1c,qGN1b,qFGW1b and qFGW1c).Five panicle trait QTLs(qSBN2,qSN2,qBN2b,qFGW2 and qGD2b)were located in the 2-136-RM498 interval of chromosome 2.Five panicle trait QTLs(qPL3,qSBN3a,qSN3,qGN3 and qGD3a)were located at the interval of RM231-R3M10 on chromosome 3.The RM2848-RM273 interval of chromosome 4 was located to 7 panicle traits(qPW4,qPBN4,qSBN4,qSN4,qGN4a,qFGW4 and qGD4).