| Rice is one of the most important food crops in the world and one of the main food rations in China.With changes in the global environment,China,as a country with a large population,will ensure steady and increased yields without increasing its planting area.At present,the breeding potential of cultivated rice is limited,while wild rice retains a large number of good genes through natural selection,which will help us cope with the current predicament.In this study,161 backcross recombinant inbred lines(BC1F12)were constructed from Dongxiang wild Rice as donor parents and cultivated rice Xieqingzao B as recipient parents.Molecular marker technology was used to construct genetic maps and rice chip was used to map QTLs for agronomic traits.The main results are as follows:1.According to the nucleotide sequence difference between the two parents,we used 1087 molecular markers that were evenly distributed on 12 chromosomes of rice in indica and japonica rice background available in the laboratory,and conducted polymorphism screening between the parents.120 polymorphic molecular markers were evenly distributed on 12 chromosomes of rice,and the polymorphism frequency was 11.78%.There were an average of 10 polymorphic markers on each chromosome,and the coverage density was 3.21MB.2.Fourteen agronomic characters,including plant height,panicle length,grain length.grain width,grain aspect ratio,1000-grain weight,chalky grain percentage,hull color,pericarp color,flowering date(time interval from first panicle to last panicle),heading date,flag leaf width,germination rate and percentage of glume weight,were investigated and statistically analyzed in 161 backcross recombinant inbred lines.The results showed that the phenotypes in both Yangzhou and Hainan populations showed hyperaffinity distribution,indicating that these traits may be controlled by multiple genes.3.A total of 11 QTLs were detected for 14 agronomic traits in rice using 161 backcross recombinant inbred lines.The QTLs were identified for plant height,panicle length,grain length,grain width,grain aspect ratio,1000-grain weight,and percentage of glume weight.Two plant height related QTLs were identified on chromosome 1 of rice.The contribution rate of qPH-1-1 and qPH-1-2 were 14.58%,15.11%,and the additive effect were-13.46cm and14.38cm,respectively.qPH-1-1 was detected in Hainan,Yangzhou.One panicle length related QTL was identified on chromosome 3,and the contribution rate was 9.75%,and the additive effect was 0.19cm.Two QTLs related to grain length were detected on chromosomes 3 and 8,namely,qGL-3-1 and qGL-8-1,with contribution rates of 11.48%and 7.56%,respectively,and additive effects of 0.50mm and-0.44mm,respectively.qGL-3-1 was detected in both Yangzhou and Hainan.One grain width related QTL,qGW-7-1,was detected on chromosome 7 of rice with a contribution rate of 13.84%and additive effect of-0.13mm.Two QTLs related to grain aspect ratio were detected on chromosomes 3 and 7,namely,qGAR-3-1 and qGAR-71,with contribution rates of 10.81%and 14.82%,and additive effects of 0.22 and 0.21,respectively.qGAR-3-1 was detected in both Yangzhou and Hainan.Two thousand-grain weight related QTLs,qTGW3-1 and qTGW3-2,were detected on chromosome 3,with contribution rates of 12.61%and 6.80%,and additive effects of 1.55g and 1.88g,respectively.A QTL related to percentage of glume weight was detected on chromosome 5 of rice:qPOG5-7,with a contribution rate of 6.13%and additive effect of-1.00%.4.A total of 32 QTLs were detected by RICE microarray in plant height,panicle length,grain length,grain width,grain aspect ratio,1000-grain weight,chalky grain percentage,flowering date,heading time,percentage of glume weight.The localization of the chip is so fine that it can even locate cloned genes directly.One QTL related to plant height,qPH-1-3,was identified on chromosome 1 of rice with a contribution rate of 38.15%and additive effect of-23.79cm,which could be detected in both Yangzhou and Hainan.Seven QTLs related to panicle length were detected on chromosomes 1,3,5 and 7.with contribution rates ranging from 4.82%to 22.22%and additive effects ranging from-2.17 to 1.71cm.Two QTLs related to grain length were detected on chromosome 1 and chromosome 3,namely,qGL-1-1 and qGL-3-2,with contribution rates ranging from 4.32%to 29.23%,and additive effects of 0.22mm and 0.54mm,respectively.qGL-3-2 was detected in both Yangzhou and Hainan.Two QTLs related to grain width were detected on chromosome 5 of rice:qGW-5-1 and qGW-5-2,the contribution rates were 9.43%and 8.67%,and the additive effects were-0.08mm and 0.003mm,respectively.Seven QTLs related to grain aspect ratio were detected on chromosomes 1,3,5,8,10 and 12,with contribution rates ranging from 4.71%to 28.36%and additive effects ranging from-0.01 to 0.18cm.Six thousand-grain weight related QTLs were detected on chromosomes 1,2,3,5 and 6,with contribution rates ranging from 5.21%to 17.82%and additive effects ranging from-0.08 to 1.79g.Three QTLs related to chalky grain percentage were detected on chromosomes 5 and 6 of rice:qCGP-5-1,qCGP-5-2 and qCGP6-1,with contribution rates of 8.3 1%,15.59%and 7.79%,respectively,and additive effects of-8.24%,12.40%and 9.30%,respectively.Two QTLs related to flowering date were detected on chromosome 1 and chromosome 8,qFD-1-1 and qFD-8-1,with contribution rate of 11.86%and 7.89%,and additive effect of 3.00day and 0.03day,respectively.One QTL related to flowering length,qHD-7-1,was detected on chromosome 7,and the contribution rate was 5.83%,and the additive effect was-3.24day.One QTL,qPOG-5-2,was detected on chromosome 5 of rice with a contribution rate of 6.49%and additive effect of-1.00%. |
