Genetic Analysis And Gene Mapping Of A Small Grain Dwarf Mutant Of Rice

In order to identify the genetic characteristics of the small grain with dwarfmutant guangxiaoli and the OsSGD gene’s function in rice. In this paper, the somemajor agronomic traits of the mutant guangxiaoli were investigated, as well as thegenetic analysis and the gene mapping of OsSGD were done. The main results asfollows1. The investigation results showed that1000-grain weight and plant height ofmutant guagnxiaoli were significant different from wild variety guangzhan63S.Comparing with variety guangzhan63S,1000-grain weight reduced to11.83g from22.77g and plant height reduce to38.60cm from80.90cm. Analysis of varianceindicated that the difference of those traits between two varieties was significantly.The1000-grain weight decreas of Guangxiaoli was due to the grain length decreas. Inaddition, the leaf length and the spike length of guangxiaoli were both shorter thanguangzhan63S.2. The genetic analysis showed that the small grain trait was controlled by asingle recessive genes, which was named OsSGD(Oryza sativa small grain dwarf).3. Based on the SSR markers and BSA analysis, the OsSGD gene was mapped onthe5th chromosome of rice and flanked by RM18157and RM598. The geneticdistance of RM18157and RM598to OsSGD gene was2.22cM and2.68cM,respectively.4. Based upon the primary mapping, a series of SSR marker was designed forfine mapping the OsSGD gene. The results showed that RM18398and RM18413were the closestly linked markers, the genetic distance of them to OsSGD gene was0.12cM and0.23cM, respectively. The physical distance from RM18398toRM18413was474kb. And the RM18399and RM18405were the co-segregatedmarkers.