The Genetic Mapping And Analysis Of Rice Semi-dwarf Gene

The discovery and application of the rice dwarf gene sd1 succeeded in triggering the first "green revolution" of agriculture to show that dwarfing genes were excavated and utilized.Howeverlong-term overuse of single genes has also brought about a series of ecological crisis potential genetic diversity loss and breed quality reduction such as drought resistance,disease resistance.In this study the material M22-3-2 is a dwarf mutant obtained from indica-compatible Japonica M22-3-1,M22-3-2 belongs to dn-dwarf type with short and thick leaves,mutiple tillers and few spikelets plant height is 72.8 ± 1.05 cm,the experiment uses rice semi-dwarf indica rice varieties Minghui63 hybridized with the mutant M22-3-2 and constructed the locifor fine mapping.The following findings were obtained:1.Material M22-3-2 belongs to dn-dwarf type with short and thick leaves,mutiple tillers and few spikelets.2.There is only one pair of dwarf genes between the mutant M22-3-2 and M22-3-1 and the semi-dwarf species Minghui 63.3.A number of polymorphic markers were developed during the fine sdm gene mapping,and nine pairs of primers were obtained for further fine mapping by polymorphism analysis.4.In this study,sdm was mapped to a region between the chromosome marker RIDM-197001 and the marker RM7102 with the physical distance 1900 kb.5.There are 75 candidate genes in the range of 1900 kb between the labeled RIDM-197001 and the marker RM7102.The phenotypic analysis of the candidate gene and the sdm mutant suggests that the sdm gene may be a class of genes that control GA synthesis and its signal transduction.There is no report of relevant dwarf genesin the region containing sdm on chromosome 12.So sdm is a newly excavated dwarf QTL for the subsequent fine mapping and candidate gene analysis,layingthefoundation for successful cloning of the gene.