QTL Mapping Of Some CULM Charactors Related To Lodging Resistance In Wheat

Wheat lodging is an important factor in restricting the production and quality of wheat. Around the world, wheat lodging caused great losses to wheat production every year. The wheat production survey showed that the yield of wheat would lose 30% if loding happened during booting to flowering stage,10%-20% during filling stage, and 10%-15% during milky stage.Ningmai 9 and Yangmai 158 are the main cultivars planted large areas in the Yangtze River region. Lodging resistance in Ningmai 9 is less than that in Yangmai158, to identify the QTL associated with lodging resistance will contribute to the use of marker-assisted selection for lodging resistance breeding, which can improve the lodging resistance of Ningmai 9 and other varieties.A RIL Population with 188 lines, derived from the cross of Ningmai9/Yangmai 158, was used to identify QTLs for stem strength, plant height, the length of first basal internode and second basal internode in this study. The results are summarized as follows:1. The stem strength of RIL population is ranged from 2.15N to 12.99 N with the average value of 5.16N. The stem strength is 5.08N in Ningmai 9 whereas 6.33N in Yangmai158; the plant height of RIL population is ranged from 69.60cm to 109.00cm with the average value of 84.64cm. The plant height is 76.68cm in Ningmai 9 whereas 99.80cm in Yangmai158. The length of first basal internode of RIL population is ranged from 2.80cm to 9.46cm with the average value of 4.95cm,. The length of first basal internode is 4.63cm in Ningmai 9 whereas 6.45cm in Yangmai158. The length of second basal internod of RIL population is ranged from 7.24cm to 10.36cm with the average value of 8.08cm. The length of second basal internod is 6.21cm in Ningmai 9 whereas 11.82cm in Yangmai 158. These traits are in line with the normal distribution, the differences between the groups repeat is not obvious.2. The result of genotype analyze for the RIL population with 164 polymorphic loci. A genetie linkage map is constructed by Joinmapping3.0 Program, which covering 20 chromosomes with an average interval length of 12.28cM, and the smallest interval length is 3.3cM.The chromosomes are 1A, 1B, 1D,2A,2B,2D,3A,3B,3D,4A,4B,4D,5A,5B, 5D,6B,6D,7A,7B,7D.3. QTLs for stem strength are located on chromosome 6B,2B,7A. The QTL on chromosome 2B is between wmc332 and wmc41, with the LOD value of 3.22 and the contribution rate of 7.20%; The QTL on chromosome 6B is between wmc398 and wmc105, the LOD value is 2.04 and the contribution rate is 4.30%; The QTL on chromosome 7A is between wmc603 and wmc438, the LOD value is 2.60 and the contribution rate is 6.92%.4. QTLs for plant height are located on chromosome 2B, one is between wmc597 and barc55, with the LOD value of 2.86 and the contribution rate of 6.30%, Additive effect are from Ningmai 9, another is between wmc332 and wmc41, with the LOD value of 2.23 and the contribution rate of 8.15%.5. QTLs for the length of first basal internode are located on chromosome 7A,3A,2A. the QTL on chromosome 7A is between B155 and gwm635, with the LOD value of 2.65 and the contribution rate of 5.16%, the QTL on chromosome 3A is between barc314 and cfa2193, with the LOD value of 3.37 and the contribution rate of 6.47%; the QTL on chromosome 2A is between barc212 and wmc636,with the LOD value of 4.17 and the contribution rate of 8.84%.6. QTLs for the length of second basal internode are located on chromosome 3A,2A.The QTL on chromosome 3A is between barc314 and cfa2193, which is LOD value of 3.40 and the contribution rate of 6.80%; the QTL on chromosome 2A is between barc212 and wmc636,which is LOD value of 3.33 and the contribution rate of 8.23%.7. To locate QTL can provide a basis for genetic research and marker-assisted selection in this article.