Dissection And QTL Mapping Of Culm Strength In Rice(Oryza Sativa.L)

The lodging of rice happened at milk ripe stage can make a decrease in agric-ultural production more than 30%.Since the breeders come up with improving the biological yieldby increasing plant height,the resistance to lodging of ri-c e can not blindly rely ondwarfing,the study of the reinforce of stem streng-th is one of the most important research about how to enhance the resistance t o lodging.Thisstudy uses Ming 63 as the recurrent parent andAF099 as t-he d onor parent which is a new strains with strong stem strength created BC₂F₄ as the materials.We selected 82 valid markup distributed on 12 chromoso-mes fo r genotypeanalysis,We analyze the the phenotype data and QTL mappi-ng ab out strength of three internodes.The main results were as follows:1.In year 2013,2014,2015,the stem strength of the first internode,the seco-nd internode and the third internode is significantly positive correlated,and the correlation coefficient is large.2.There are 97 QTLsabout three internodes were detected through the analys-i s of character-single variance,There are respectively36,34,27 QTLs were d-et ected in year 2013,2014,2015.Four QTLs which control three internode's stem strength were detected in year 2013;Six QTLs which control two internode's stem strength were detected.Four QTLs which control three internode's stem s trength were detected in year 2014;Seven QTLs which control two internod-e's stem strength were detected.Tow QTLs which control three internode's st-em strength were detected in year 2015;Four QTLs which control two intern-od e's stem strength were detected.3.The locus closely linked with Marker RM318 were detected in three years,and the locus contemporary control three internode's stem strength.The additive effect of this locus were negative,the beneficial genes come from the donor parent.The locus closely linked with Marker RM515 were detected in years 2013 and 2014,and the locus contemporary control three internode's stem strength.The additive effect of this locus were negative,the beneficial genes come from the donor parent.4.There are 73 strains which are highly significant with recurrent parent were selected.There are 58 strains'first internode's stem strength are highly signifi-cant with recurrent parent,There are 10 strains'second internode's stem strengt-h are highly significant with recurrent parent,There are also five strains'third internode‘s stem strength are highly significant with recurrent parent.5.The locus qCS?2.1,qCS?3.2,qCS?10.1were detected in the select-e d plant about the first internode.these locus'beneficial genes come from the re current parent.The locus qCS?.2.5 and qCS?.11.2 were detected in the s elected plant about the second internode.The locus qCS?.10.1 detected in th e selected plant about the third internode,these locus'beneficial genes come fro m the recurrent parent.The locus qCS?.1.1 detected in the selected plant ab out the third internode,these locus'beneficial genes come from the donor paren t.