QTL Mapping Based On Single Segment Substitution Lines (SSSLs) And Development Of Molecular Markers For Sugarcane Mosaic Virus (SCMV) Resistance In Maize

Many important agronomic traits are quantitative. It is very important to accurately identify and finely map quantitative trait loci (QTL). In our experiment, a series of single segment Substitution lines (SSSLs) in an elite inbred line 87-1 gnetic background of maize was developed. QTL mapping with the SSSLs at Zhengzhou and Sanya in 2008. In this study, conserved domains of disease-resistant genes were investigated within the consensus SCMV-resistance QTL on the maize bin 6.00-6.01, and furthermore the polymorphic sequences were used to develop markers InDel-130 and InDel-110. The main results are as follows:1. A series of chromosome single segment substation lines was developed, included 57 SSSLs with one homogeneous donor segment and recipient background was developed. The 57 SSSLs were distributed on all 10 chromosomes unevenly. In the 57 SSSLs, the donor segment length is 1111.45 cM in total, the average lengenth was 19.50 cM , the maize coverd genome length was 907.70cM, the coverage was 39.09% of maize genome.2. QTL mapping of grain yield and its components with the SSSLs at Zhengzhou and Sanya in 2008. 30 QTL was detected in 22 SSSLs in Zhengzhou, and 53 QTL was detected in 39 SSSLs in Sanya, the total QTLs was 83 in two sites. The average of each chromosome was was detected with 8.3 SSSLs, each segment was 1.73, each character was 11.86. Compare the same SSSL material in two sites, .it was found that 56 QTLs was detected in the same 17 SSSLs, and 42 QTLs was found in two sites, the percentage was 75% , the average of each repeat SSSLs was 2.47.3. Conserved domains of disease-resistant genes were investigated within the consensus SCMV-resistance QTL on the maize bin 3.04-3.05 and bin 6.00-6.01, and furthermore the polymorphic sequences were used to develop markers InDel-186 and InDel-130, InDel-110 and susceptible marker genotypes in 102 inbred lines, It was investigated in 379 individuals of [(Ye478×Hai9-21)×Ye478] BC2F2 population and 183 lines of (X178xB73) RIL population evaluated under field condition with artificial inoculation, respectively.Furthermore, the DNA extraction, PCR amplification, and electrophoresis procedures were optimized for two markers InDel-186 and InDel-110. As a result, InDel-186,InDel-110 that was significantly associated with SCMV resistance. It was suggested that the maize breeding materials with SCMV resistance would be effectively obtained by marker-assisted selection approach with InDel-186 and InDel-110.